Homomorphic encryption-based communication method and apparatus

Abstract

The present application provides a homomorphic encryption-based communication method and apparatus. The method comprises: a key generator obtaining a first key parameter, wherein the first key parameter is a key parameter related to an updated root key of a network device accessed by a terminal device; and on the basis of the first key parameter and a homomorphic encryption and decryption algorithm, the key generator deriving a homomorphic encryption and decryption key, wherein the homomorphic encryption and decryption key is used for a homomorphic task in which the terminal device participates. Hence, in the communication system, when information of the homomorphic task in which the terminal device participates changes, the key generator can, on the basis of an updated superior key of a homomorphic key, re-derive the homomorphic key for the homomorphic task, thereby ensuring the continuity of the homomorphic task of the terminal device.

Description

Communication method and communication device based on homomorphic encryption Technical Field

[0001] The present application relates to the field of wireless communication technology, and more specifically, to a communication method and communication device based on homomorphic encryption. Background Art

[0002] To improve the security and privacy of data usage, homomorphic encryption technology can be used to complete the computation and processing of ciphertext data without exposing the plaintext data, thereby realizing the mining of data value while providing privacy protection. For homomorphic tasks, if the homomorphic participants (homomorphic encryptors, homomorphic decryptors, homomorphic computation parties, etc.) are terminal devices, base stations, network elements, and other devices located in wireless communication networks, when the homomorphic participants in the homomorphic tasks or related information such as homomorphic encryption and decryption keys in the homomorphic tasks participated by the terminal devices change, how to ensure the continuity of the homomorphic tasks participated by the terminal devices is an urgent problem that needs to be solved.

[0003] Summary of the Invention

[0004] This application provides a communication method based on homomorphic encryption, which can ensure the continuity of homomorphic tasks.

[0005] In the first aspect, a communication method based on homomorphic encryption is provided. The method can be executed by a key generator, or it can also be executed by a component of the key generator (such as a chip or circuit), without limitation. For the sake of ease of description, the following is an example of execution by the key generator. The method may include: the key generator obtains a first key parameter, the first key parameter is a key parameter of the updated root key of the network device to which the terminal device is connected; the key generator derives a homomorphic encryption and decryption key based on the first key parameter and the homomorphic encryption and decryption algorithm, and the homomorphic encryption and decryption key is used for the homomorphic task in which the terminal device participates.

[0006] In the above scheme, in the communication system, when the superior key of the homomorphic key corresponding to the homomorphic task in which the terminal device participates changes, the key generator can re-derive the homomorphic key used for the homomorphic task based on the superior key of the updated homomorphic encryption and decryption key (the root key of the network device to which the terminal device accesses), thereby ensuring the continuity of the homomorphic task of the terminal device.

[0007] In one possible implementation, when the key generator is a first network device, the key generator obtains a first key parameter, including: the first network device receives the first key parameter from a second network device, the second network device is a network device accessed before the terminal device switches, and the first network device is a network device accessed after the terminal device switches; or, the first network device generates the first key parameter, and the first network device is a network device accessed by the terminal device.

[0008] In the above scheme, when the network device to which the terminal device is connected is switched, causing the superior key of the homomorphic key corresponding to the homomorphic task in which the terminal device participates to change, the first network device (the network device to which the terminal device is connected after the switch) can obtain the updated superior key to re-derive the homomorphic key, thereby ensuring the continuity of the homomorphic task.

[0009] In one possible implementation, when the key generator is the first network device, the method further includes: the first network device receiving homomorphic capability information of the terminal device; and the first network device determining a homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device.

[0010] In the above solution, the first network device can determine the homomorphic encryption and decryption algorithm used to generate the homomorphic encryption and decryption key based on the homomorphic capability information of the terminal device corresponding to the homomorphic task, thereby ensuring the smooth execution of the homomorphic task.

[0011] A possible implementation method is that when the key generator is the first network device, the first network device determines the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device, including: the first network device receives the homomorphic capability information of the third network device; the first network device determines the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device, and the third network device is a device participating in executing the homomorphic task.

[0012] In the above scheme, the first network device can further determine the homomorphic encryption and decryption algorithm used to generate homomorphic encryption and decryption keys based on the homomorphic capability information of other homomorphic participants in the homomorphic task, thereby ensuring the smooth execution of the homomorphic task.

[0013] In a possible implementation manner, when the key generator is a first network device, the method further includes: the first network device sends first indication information to the terminal device, where the first indication information is used to indicate an identifier of the homomorphic encryption and decryption algorithm.

[0014] In the above solution, the first network device indicates the homomorphic encryption and decryption algorithm used to generate the homomorphic encryption and decryption key to the terminal device, so that the terminal device can generate the same homomorphic encryption and decryption key to complete the homomorphic task.

[0015] In a possible implementation manner, the first indication information is sent via non-access stratum (NAS) signaling.

[0016] In the above solution, after the first network device determines the homomorphic encryption and decryption algorithm, it indicates it to the terminal device, so that the terminal device further re-derives the same homomorphic key based on the homomorphic encryption and decryption algorithm.

[0017] In a possible implementation manner, when the key generator is the first network device, the method further includes: the first network device receiving an identifier of the homomorphic encryption and decryption algorithm from a homomorphic encryption control function (HECF).

[0018] In the above solution, the HECF with homomorphic management capability can determine the algorithm for determining the homomorphic key and indicate it to the first network device, so that the first network device further derives the homomorphic key.

[0019] Among them, HECF can perform key management of homomorphic tasks (for example, derivation and distribution of homomorphic keys, update and management of homomorphic keys, etc.), capability management of homomorphic tasks (for example, generation and storage of homomorphic capability files), homomorphic task management (for example, homomorphic task request management, homomorphic task scheduling management, etc.), etc., and this application does not limit this.

[0020] In a possible implementation manner, when the key generator is a homomorphic management device HECF, the key generator obtains the first key parameter, including: HECF generates the first key parameter.

[0021] In the above scheme, when the network device to which the terminal device is connected switches, causing the superior key of the homomorphic key corresponding to the homomorphic task in which the terminal device participates to change, HECF can update the root key (the superior key of the homomorphic key) corresponding to the network device to which the terminal device is connected to re-derive the homomorphic key, thereby ensuring the continuity of the homomorphic task.

[0022] In a possible implementation manner, the method further includes: the HECF receiving homomorphic capability information of the terminal device; and the HECF determining a homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device.

[0023] In the above scheme, HECF can determine the homomorphic encryption and decryption algorithm used to generate homomorphic encryption and decryption keys based on the homomorphic capability information of the terminal device corresponding to the homomorphic task, thereby ensuring the smooth execution of the homomorphic task.

[0024] In one possible implementation, HECF determines a homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device, including: HECF receives the homomorphic capability information of a third network device; HECF determines the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device, where the third network device is a device participating in executing the homomorphic task.

[0025] In the above scheme, HECF can further determine the homomorphic encryption and decryption algorithm used to generate homomorphic encryption and decryption keys based on the homomorphic capability information of other homomorphic participants in the homomorphic task, thereby ensuring the smooth execution of the homomorphic task.

[0026] In a possible implementation manner, the method further includes: HECF sending homomorphic encryption and decryption keys to the first network device and the terminal device, where the first network device is the network device accessed by the terminal device.

[0027] In the above scheme, after the HECF with specific homomorphic management capabilities re-derives the homomorphic encryption and decryption keys, the homomorphic encryption and decryption keys are sent to the homomorphic encryption party and the homomorphic decryption party (the first network device and the terminal device) so that the homomorphic encryption party and the homomorphic decryption party can perform homomorphic tasks.

[0028] A possible implementation method is that when the key generator is a terminal device, the key generator obtains a first key parameter, including: the terminal device receives a second indication information from a first network device, the second indication information is used to indicate that a root key of a network device to which the terminal device is connected is updated, and the first network device is a network device to which the terminal device is connected; the terminal device generates a first key parameter based on the second indication information.

[0029] In the above scheme, the terminal device can obtain information about changes in the superior key of the homomorphic key corresponding to the homomorphic task in which the terminal device participates according to the instructions of the first network device, and then the terminal device generates an updated superior key according to the preconfigured algorithm to ensure the continuity of the homomorphic task.

[0030] In a possible implementation manner, the second indication information is sent via NAS security mode signaling in a mobility registration update procedure or handover signaling in a cell handover procedure.

[0031] In a possible implementation manner, the method further includes: the terminal device receives first indication information from the first network device or HECF, where the first indication information is used to indicate an identifier of the homomorphic encryption and decryption algorithm.

[0032] In the above scheme, the terminal device can obtain the homomorphic encryption and decryption algorithm used to generate homomorphic encryption and decryption keys according to the instructions of the first network device or HECF, and use it to derive homomorphic encryption and decryption keys to complete the homomorphic task.

[0033] A possible implementation method is that a key generator derives a homomorphic encryption and decryption key based on a first key parameter and a homomorphic encryption and decryption algorithm, including: the key generator derives the homomorphic encryption and decryption key based on the first key parameter, the homomorphic encryption and decryption algorithm and a second key parameter, and the second key parameter includes at least one of the following: an identifier of the homomorphic encryption and decryption algorithm, a ciphertext modulus, a plaintext modulus, and a polynomial dimension.

[0034] In a possible implementation, the method further includes: the key generator obtains the homomorphic task requirements, and the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task; wherein the key generator derives the homomorphic encryption and decryption key based on the first key parameter and the homomorphic encryption and decryption algorithm, including: when the key generator determines that the third network device meets the homomorphic task requirements, the key generator derives the homomorphic encryption and decryption key based on the first key parameter, the homomorphic encryption and decryption algorithm, and the homomorphic task requirements, and the third network device is a device participating in executing the homomorphic task.

[0035] In the above scheme, when the key generator determines that the homomorphic participants meet the homomorphic task requirements, the key generator further derives the homomorphic encryption and decryption keys, avoiding unnecessary key derivation and saving resources.

[0036] In a possible implementation manner, the homomorphic capability information includes at least one of the following: homomorphic capability type, homomorphic encryption and decryption algorithm identifier, homomorphic computing function identifier, security level, decryption circuit depth, and complexity of the ciphertext computing circuit; the homomorphic task information includes at least one of the following: homomorphic task role, homomorphic computing key, homomorphic computing key size, ciphertext modulus, plaintext modulus, upper limit of noise distribution, number of decimal places corresponding to the calculation accuracy, ciphertext computing vector dimension n, homomorphic encryption algorithm identifier, and homomorphic computing function identifier.

[0037] In the second aspect, a communication method based on homomorphic encryption is provided. The method can be executed by a second network device, or it can also be executed by a component of the second network device (such as a chip or circuit), without limitation. For the sake of ease of description, the following is an example of execution by the second network device. The method may include: the second network device receives a homomorphic key from the first network device or the homomorphic management device HECF and information about the homomorphic task of the terminal device, the homomorphic key is used to execute the homomorphic task; the second network device executes the homomorphic task according to the homomorphic key and the homomorphic task information, wherein the first network device is the network device accessed before the terminal device switches, and the second network device is the network device accessed after the terminal device switches.

[0038] In the above scheme, when the relative position of the terminal device and the network device changes, and the homomorphic computing party of the homomorphic task corresponding to the terminal device changes, the new homomorphic computing party (the second network device) can obtain the homomorphic key, homomorphic task requirements and other homomorphic task related information from the old homomorphic computing party (the first network device) or the HECF with homomorphic management capabilities to complete the homomorphic task, thereby ensuring the continuity of the homomorphic task in which the terminal device participates.

[0039] In one possible implementation, before the second network device receives the homomorphic key from the homomorphic management device HECF and the information of the homomorphic task of the terminal device, the method also includes: the second network device receives the homomorphic task requirement from the first network device, and the homomorphic task requirement is used to indicate the parameters required to execute the homomorphic task; the second network device sends the homomorphic task requirement and the homomorphic capability information of the second network device to the homomorphic management device HECF, wherein the homomorphic calculation key is determined based on the homomorphic task requirement and the homomorphic capability information of the second network device.

[0040] In the above scheme, when the new homomorphic computing party only receives homomorphic task requirements from the old homomorphic computing party, the new homomorphic computing party can forward the homomorphic task requirements to HECF, so that HECF determines the corresponding homomorphic key and homomorphic task information based on the homomorphic task requirements, and sends them to the new homomorphic computing party. In this way, HECF uniformly manages homomorphic tasks, enabling HECF to timely obtain changes in all homomorphic tasks in the associated management area, update and manage the homomorphic keys, homomorphic task information, and homomorphic capability information of different nodes related to all homomorphic tasks, and make appropriate scheduling arrangements based on the effective computing resources, storage resources, and homomorphic task requirements of different nodes.

[0041] In one possible implementation, the second network device is the target base station, the first network device is the source base station, and the homomorphic computing key and homomorphic task information are sent through the Xn interface.

[0042] In one possible implementation, before the second network device receives the homomorphic key and homomorphic task information from the first network device or the homomorphic management device HECF, the method also includes: the second network device receives a switching request information from the first network device, and the switching request information is used to instruct the network device to which the terminal device is connected to switch; the second network device sends a switching response information to the first network device, and the switching response information is used to indicate that the network device to which the terminal device is connected can switch to the second network device.

[0043] In the above scheme, when the homomorphic computing party of the homomorphic task changes due to the switching of the network device to which the terminal device is connected, the new homomorphic computing party (the second network device) can obtain the homomorphic key, homomorphic task requirements and other homomorphic task-related information from the old homomorphic computing party (the first network device) or the HECF with homomorphic management capabilities to complete the homomorphic task.

[0044] In one possible implementation, the switching request information includes homomorphic task requirements, and the second network device sends switching response information to the first network device, including: when the second network device determines that the homomorphic task requirements are met, the second network device sends switching response information to the first network device.

[0045] In one possible implementation, before the second network device receives the homomorphic key and homomorphic task information from the first network device or the homomorphic management device HECF, the method also includes: the second network device receives radio resource control RRC wake-up request information from the terminal device, and the RRC wake-up request information is used to request that the terminal device be switched from a non-connected state to a connected state; the second network device sends a request information for obtaining a terminal device context to the first network device; wherein the second network device receives the homomorphic key and homomorphic task information from the first network device or the homomorphic management device HECF, including: the second network device receives a response information for obtaining a terminal device context from the first network device, and the response information for obtaining a terminal device context includes information about the homomorphic key and the homomorphic task.

[0046] In the above scheme, when the homomorphic computing party of the homomorphic task changes due to a change in the connection status of the terminal device, the new homomorphic computing party (the second network device) can obtain the homomorphic computing key, homomorphic task requirements and other homomorphic task-related information from the old homomorphic computing party (the first network device) or the HECF with homomorphic management capabilities to complete the homomorphic task.

[0047] In one possible implementation, after the second network device receives the homomorphic key and homomorphic task information from the first network device or the homomorphic management device HECF, the method also includes: the second network device sends RRC wake-up information to the terminal device, and the RRC wake-up information is used to instruct the terminal device to switch from a non-connected state to a connected state.

[0048] In one possible implementation, the second network device sends RRC wake-up information to the terminal device, including: when the second network device determines that the cell served by the second network device meets the homomorphic task requirements, the second network device sends RRC wake-up information to the terminal device.

[0049] In one possible implementation, the second network device is a second core network element, the first network device is a first core network element, the first core network element is a network device of a cell before the service terminal device is switched, and the second core network element is a network device of a cell after the service terminal device is switched, and the information of homomorphic keys and homomorphic tasks is sent through the Ng interface.

[0050] In one possible implementation, the homomorphic capability information includes at least one of the following: homomorphic capability type, homomorphic encryption and decryption algorithm identifier, homomorphic computing function identifier, security level, decryption circuit depth, and complexity of the ciphertext computing circuit.

[0051] In one possible implementation, the information of the homomorphic task includes at least one of the following: homomorphic task role, homomorphic computing key, homomorphic computing key size, ciphertext modulus, plaintext modulus, upper limit of noise distribution, number of decimal places corresponding to the calculation accuracy, ciphertext computing vector dimension n, homomorphic encryption algorithm identifier, and homomorphic computing function identifier.

[0052] In a third aspect, a communication method based on homomorphic encryption is provided. The method can be executed by a homomorphic management device HECF, or it can also be executed by a component of HECF (such as a chip or circuit), without limitation. For the sake of ease of description, the following is an example of execution by HECF. The method may include: the homomorphic management device HECF determines a homomorphic key based on the homomorphic task requirements and the homomorphic capability information of the second network device, the homomorphic key is used to execute the homomorphic task of the terminal device, and the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task; the homomorphic management device HECF sends the homomorphic key and homomorphic task information to the second network device, wherein the second network device is the network device to which the terminal device is connected after switching.

[0053] In the above scheme, when the relative position of the terminal device and the network device changes, and the homomorphic computing party of the homomorphic task corresponding to the terminal device changes, the HECF with homomorphic management capabilities can re-derive or search for the homomorphic key for the homomorphic task locally according to the homomorphic task requirements and the homomorphic capabilities of the new homomorphic computing party, and send it to the new homomorphic computing party to complete the homomorphic task, thereby ensuring the continuity of the homomorphic task in which the terminal device participates.

[0054] In a possible implementation manner, the method further includes: the homomorphic management device HECF receives the homomorphic task requirements and homomorphic capability information of the second network device from the second network device.

[0055] In one possible implementation, before HECF determines the homomorphic key based on the homomorphic task requirements and the homomorphic capability information of the second network device, the method also includes: HECF receives indication information from the second network device, and the indication information is used to instruct the network device to which the terminal device is connected to switch.

[0056] In the above scheme, when the network device to which the terminal device is connected switches and causes the homomorphic computing party of the homomorphic task to change, HECF can send the homomorphic key to the new homomorphic computing party according to the instruction information sent by the terminal device to ensure the continuity of the homomorphic task.

[0057] In a fourth aspect, a communication method based on homomorphic encryption is provided. The method can be executed by a first network device, or it can also be executed by a component of the first network device (such as a chip or circuit), without limitation. For the sake of ease of description, the following is an example of execution by the first network device. The method may include: a first network device receives first information from a second network device, the first information is used to indicate that the second network device meets the homomorphic task requirements, and the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task of the terminal device; the first network device sends a homomorphic key and homomorphic task information to the second network device, and the homomorphic key and homomorphic task information are used to execute the homomorphic task; wherein the first network device is a network device accessed before the terminal device switches, and the second network device is a network device accessed after the terminal device switches.

[0058] In the above scheme, when the relative position of the terminal device and the network device changes, and the homomorphic computing party of the homomorphic task corresponding to the terminal device changes, the old homomorphic computing party will send the homomorphic key used for the homomorphic task to the new homomorphic computing party when it determines that the homomorphic capability of the new homomorphic computing party meets the requirements of the homomorphic task, so as to complete the homomorphic task, thereby ensuring the continuity of the homomorphic task in which the terminal device participates.

[0059] In one possible implementation, the second network device is the target base station, the first network device is the source base station, and the homomorphic computing key and homomorphic task information are sent through the Xn interface.

[0060] In one possible implementation, before the first network device sends information about a homomorphic key and a homomorphic task to the second network device, the method further includes: the first network device determines that the network device to which the terminal device is connected is switched; the first network device sends a switching request message to the second network device, where the switching request message is used to instruct the network device to which the terminal device is connected to switch; the first network device receives a switching response message from the second network device, where the switching response message is used to indicate that the network device to which the terminal device is connected can be switched to the second network device; the first network device sends a switching command to the terminal device, where the switching command is used to instruct the network device to which the terminal device is connected to switch to the second network device.

[0061] In the above scheme, when the homomorphic computing party of the homomorphic task changes due to the switching of the network device to which the terminal device is connected, the old homomorphic computing party (the first network device) sends the homomorphic key, homomorphic task requirements and other related information of the homomorphic task to the new homomorphic computing party (the second network device) to complete the homomorphic task.

[0062] In one possible implementation, before the first network device sends information about a homomorphic key and a homomorphic task to the second network device, the method further includes: the first network device sends a request message for obtaining a terminal device context to the second network device; wherein the first network device sends information about a homomorphic key and a homomorphic task to the second network device, including: the first network device sends a response message for obtaining a terminal device context to the second network device, and the response message for obtaining a terminal device context includes information about the homomorphic key and the homomorphic task.

[0063] In the above scheme, when the homomorphic computing party of the homomorphic task changes due to a change in the connection status of the terminal device, the old homomorphic computing party (the first network device) carries the homomorphic computing key, homomorphic task requirements and other related information of the homomorphic task in the obtain terminal device context response information and sends it to the new homomorphic computing party (the second network device) to ensure the continuity of the homomorphic task.

[0064] In one possible implementation, the second network device is a second core network element, the first network device is a first core network element, the first core network element is a network device of a cell before the service terminal device is switched, and the second core network element is a network device of a cell after the service terminal device is switched, and the homomorphic computing key and the homomorphic task information are sent through the Ng interface.

[0065] In a fifth aspect, a communication device is provided, comprising a unit for executing the method shown in the first aspect above. The communication device may be a key generator, or may be executed by a chip or circuit provided in the key generator, and this application does not limit this. The communication device includes: a processing unit for obtaining a first key parameter, where the first key parameter is a key parameter of an updated root key of a network device to which the terminal device is connected; and a processing unit for deriving a homomorphic encryption and decryption key based on the first key parameter and a homomorphic encryption and decryption algorithm, where the homomorphic encryption and decryption key is used for homomorphic tasks in which the terminal device participates.

[0066] In one possible implementation, when the communication device is a first network device, the transceiver unit is used to receive a first key parameter from a second network device, where the second network device is a network device accessed before the terminal device switches, and the communication device is a network device accessed after the terminal device switches; or, the processing unit is further used to generate the first key parameter, where the communication device is a network device accessed by the terminal device.

[0067] In one possible implementation, the device further includes: a transceiver unit, further used to receive homomorphic capability information of the terminal device; and a processing unit, further used to determine the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device.

[0068] In one possible implementation, the transceiver unit is also used to receive homomorphic capability information of a third network device; the processing unit is also used to determine the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device, and the third network device is a device that participates in executing homomorphic tasks.

[0069] In a possible implementation manner, the apparatus further includes: a transceiver unit, further configured to send first indication information to the terminal device, wherein the first indication information is configured to indicate an identifier of the homomorphic encryption and decryption algorithm.

[0070] In a possible implementation manner, the device further includes: a transceiver unit, further configured to receive an identifier of a homomorphic encryption and decryption algorithm from a homomorphic management device HECF.

[0071] In a possible implementation manner, when the key generator is a homomorphic management device HECF, the processing unit is further used to generate a first key parameter.

[0072] In one possible implementation, the device further includes: a transceiver unit, further used to receive homomorphic capability information of the terminal device; and a processing unit, further used to determine the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device.

[0073] In one possible implementation, the transceiver unit is also used to receive homomorphic capability information of a third network device; the processing unit is also used to determine the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device, and the third network device is a device that participates in executing homomorphic tasks.

[0074] In a possible implementation manner, the apparatus further includes: a transceiver unit, further configured to send homomorphic encryption and decryption keys to a first network device and a terminal device, wherein the first network device is a network device to which the terminal device accesses.

[0075] In one possible implementation, when the key generating party is a terminal device, the transceiver unit is further used to receive a second indication message from a first network device, where the second indication message is used to indicate that a root key of a network device to which the terminal device is connected is updated, and the first network device is the network device to which the terminal device is connected; the processing unit is further used to generate a first key parameter based on the second indication message.

[0076] In one possible implementation, the device further includes: a transceiver unit, further used to receive first indication information from the first network device or HECF, where the first indication information is used to indicate an identifier of the homomorphic encryption and decryption algorithm.

[0077] In one possible implementation, the device also includes: a processing unit, which is also used to obtain homomorphic task requirements, and the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task; when the communication device determines that the third network device meets the homomorphic task requirements, the processing unit is also used to derive the homomorphic encryption and decryption key based on the first key parameter, the homomorphic encryption and decryption algorithm, and the homomorphic task requirements, and the third network device is a device that participates in executing the homomorphic task.

[0078] In one possible implementation, the processing unit is also used to derive a homomorphic encryption and decryption key based on a first key parameter, a homomorphic encryption and decryption algorithm, and a second key parameter, where the second key parameter includes at least one of the following: an identifier of the homomorphic encryption and decryption algorithm, a ciphertext modulus, a plaintext modulus, and a polynomial dimension.

[0079] The explanation and beneficial effects of the communication device-related contents provided in the fifth aspect can refer to the method shown in the first aspect and will not be repeated here.

[0080] In a sixth aspect, a communication device is provided, comprising a unit for executing the method shown in the second aspect above. The communication device may be a second network device, or may be executed by a chip or circuit provided in the second network device, and this application does not limit this. The communication device comprises: a transceiver unit for receiving a homomorphic key from a first network device or a homomorphic management device HECF and information about a homomorphic task of a terminal device, wherein the homomorphic key is used to execute the homomorphic task; a processing unit for executing the homomorphic task according to the homomorphic key and the information about the homomorphic task; wherein the first network device is the network device to which the terminal device is connected before switching, and the communication device is the network device to which the terminal device is connected after switching.

[0081] In one possible implementation, the transceiver unit is further used to receive homomorphic task requirements from the first network device, where the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task; the transceiver unit is further used to send the homomorphic task requirements and the homomorphic capability information of the second network device to the homomorphic management device HECF, wherein the homomorphic computing key is determined based on the homomorphic task requirements and the homomorphic capability information of the second network device.

[0082] In one possible implementation, the second network device is the target base station, the first network device is the source base station, and the homomorphic computing key and homomorphic task information are sent through the Xn interface.

[0083] In one possible implementation, the transceiver unit is further used to receive switching request information from the first network device, and the switching request information is used to instruct the network device to which the terminal device is connected to switch; the transceiver unit is further used to send switching response information to the first network device, and the switching response information is used to indicate that the network device to which the terminal device is connected can switch to the communication device.

[0084] In a possible implementation manner, the switching request information includes a homomorphic task requirement. When the communication device determines that the homomorphic task requirement is met, the transceiver unit is further configured to send a switching response information to the first network device.

[0085] In one possible implementation, the transceiver unit is further used to receive radio resource control (RRC) wake-up request information from the terminal device, where the RRC wake-up request information is used to request that the terminal device be switched from a non-connected state to a connected state; the transceiver unit is further used to send a request information for obtaining the context of the terminal device to the first network device; the transceiver unit is further used to receive a response information for obtaining the context of the terminal device from the first network device, where the response information for obtaining the context of the terminal device includes information about a homomorphic key and a homomorphic task.

[0086] In a possible implementation manner, the transceiver unit is further used to send RRC wake-up information to the terminal device, where the RRC wake-up information is used to instruct the terminal device to switch from a non-connected state to a connected state.

[0087] In one possible implementation, when the communication device determines that the cell served by the communication device meets the homomorphic task requirements, the transceiver unit is further used to send RRC wake-up information to the terminal device.

[0088] In one possible implementation, the second network device is a second core network element, the first network device is a first core network element, the first core network element is a network device of a cell before the service terminal device is switched, and the second core network element is a network device of a cell after the service terminal device is switched, and the information of homomorphic keys and homomorphic tasks is sent through the Ng interface.

[0089] In one possible implementation, the homomorphic capability information includes at least one of the following: homomorphic capability type, homomorphic encryption and decryption algorithm identifier, homomorphic computing function identifier, security level, decryption circuit depth, and complexity of the ciphertext computing circuit.

[0090] In one possible implementation, the information of the homomorphic task includes at least one of the following: homomorphic task role, homomorphic computing key, homomorphic computing key size, ciphertext modulus, plaintext modulus, upper limit of noise distribution, number of decimal places corresponding to the calculation accuracy, ciphertext computing vector dimension n, homomorphic encryption algorithm identifier, and homomorphic computing function identifier.

[0091] The explanation and beneficial effects of the communication device-related contents provided in the sixth aspect can refer to the method shown in the second aspect and will not be repeated here.

[0092] In the seventh aspect, a communication device is provided, comprising a unit for executing the method shown in the third aspect above. The communication device may be a HECF, or may be executed by a chip or circuit arranged in the HECF. This application does not limit this.

[0093] The communication device comprises:

[0094] A processing unit is used to determine a homomorphic key based on the homomorphic task requirements and the homomorphic capability information of the second network device, where the homomorphic key is used to execute the homomorphic task of the terminal device, and the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task; a transceiver unit is used to send the homomorphic key and homomorphic task information to the second network device; wherein the second network device is the network device to which the terminal device is connected after switching.

[0095] In a possible implementation manner, the transceiver unit is further configured to receive homomorphic task requirements and homomorphic capability information of the second network device from the second network device.

[0096] In a possible implementation manner, the transceiver unit is further configured to receive indication information from the second network device, where the indication information is configured to instruct the network device to which the terminal device is connected to switch.

[0097] The explanation and beneficial effects of the communication device-related contents provided in the seventh aspect can be referred to the method shown in the third aspect and will not be repeated here.

[0098] In an eighth aspect, a communication device is provided, comprising a unit for executing the method shown in the fourth aspect above. The communication device may be a first network device, or may be executed by a chip or circuit provided in the first network device, and this application does not limit this. The communication device comprises: a transceiver unit for receiving first information from a second network device, the first information being used to indicate that the second network device meets the homomorphic task requirements, and the homomorphic task requirements are used to indicate the parameters required to execute the homomorphic task of the terminal device; the transceiver unit is also used to send homomorphic keys and homomorphic task information to the second network device, and the homomorphic keys and homomorphic task information are used to execute the homomorphic task; wherein the communication device is the network device connected before the terminal device switches, and the second network device is the network device connected after the terminal device switches.

[0099] In one possible implementation, the second network device is the target base station, the communication device is the source base station, and the information of the homomorphic computing key and the homomorphic task is sent through the Xn interface.

[0100] In one possible implementation, the processing unit is used to determine whether the network device to which the terminal device is connected is switched; the transceiver unit is also used to send a switching request message to the second network device, and the switching request message is used to instruct the network device to which the terminal device is connected to switch; the transceiver unit is also used to receive a switching response message from the second network device, and the switching response message is used to indicate that the network device to which the terminal device is connected can be switched to the second network device; the transceiver unit is also used to send a switching command to the terminal device, and the switching command is used to instruct the network device to which the terminal device is connected to switch to the second network device.

[0101] In one possible implementation, the transceiver unit is further used to send a request message for obtaining the context of the terminal device to the second network device; the transceiver unit is further used to send a response message for obtaining the context of the terminal device to the second network device, and the response message for obtaining the context of the terminal device includes information about the homomorphic key and the homomorphic task.

[0102] In one possible implementation, the second network device is a second core network element, the communication device is a first core network element, the first core network element is a network device of a cell before the service terminal device is switched, and the second core network element is a network device of a cell after the service terminal device is switched, and the homomorphic computing key and the homomorphic task information are sent through the Ng interface.

[0103] The explanation and beneficial effects of the communication device-related contents provided in the ninth aspect can be referred to the method shown in the fourth aspect and will not be repeated here.

[0104] In the tenth aspect, a communication system is provided, which includes: a second network device, a homomorphic management device, and a first network device, wherein the second network device is used to execute the method of any possible implementation method of the above-mentioned second aspect, the homomorphic management device is used to execute the method of any possible implementation method of the above-mentioned third aspect, and the first network device is used to execute the method of any possible implementation method of the above-mentioned third aspect.

[0105] In the eleventh aspect, a communication device is provided, which includes: at least one processor, which is used to enable the device to execute a method of any possible implementation method of the above-mentioned first to fourth aspects by executing a computer program or instruction, and / or through a logic circuit.

[0106] In one implementation, the device is a key generator.

[0107] In one implementation, the device is a chip, a chip system, or a circuit for a key generator.

[0108] In one implementation, the device further includes a memory for storing computer programs or instructions. Optionally, the memory and the processor are integrated together.

[0109] In one implementation, the device further includes a communication interface for inputting and / or outputting signals. Optionally, the communication interface may be an input / output interface, a transceiver, a transmitter, a receiver, and the like. Unless otherwise specified, or unless otherwise inconsistent with the actual function or inherent logic in the relevant description, operations such as sending and receiving by the processor may be understood as processor output, receiving, and input operations, or as sending and receiving operations performed by the radio frequency circuit and antenna, and this application does not limit this.

[0110] In a twelfth aspect, a computer-readable storage medium is provided, which stores a program code for execution by a device, and the program code includes a method for executing any possible implementation of the above-mentioned first to fourth aspects.

[0111] In a thirteenth aspect, a computer program product comprising instructions is provided, which, when run on a computer, enables the computer to execute a method according to any possible implementation method of the first to fourth aspects above. BRIEF DESCRIPTION OF THE DRAWINGS

[0112] FIG1-1 shows a schematic diagram of a network architecture applicable to an embodiment of the present application.

[0113] Figure 1-2 shows a schematic diagram of another network architecture applicable to an embodiment of the present application.

[0114] FIG2 shows a schematic diagram of another network architecture applicable to an embodiment of the present application.

[0115] FIG3 shows a schematic diagram of a key architecture applicable to an embodiment of the present application.

[0116] FIG4 shows a schematic flowchart of a communication method 400 based on homomorphic encryption provided in an embodiment of the present application.

[0117] FIG5 shows a schematic flowchart of a communication method 500 based on homomorphic encryption provided in an embodiment of the present application.

[0118] FIG6 shows a schematic flowchart of a communication method 600 based on homomorphic encryption provided in an embodiment of the present application.

[0119] FIG7 shows a schematic flowchart of a communication method 700 based on homomorphic encryption provided in an embodiment of the present application.

[0120] FIG8 shows a schematic flowchart of a communication method 800 based on homomorphic encryption provided in an embodiment of the present application.

[0121] FIG9 shows a schematic flowchart of a communication method 900 based on homomorphic encryption provided in an embodiment of the present application.

[0122] FIG10 shows a schematic flowchart of a communication method 1000 based on homomorphic encryption provided in an embodiment of the present application.

[0123] FIG11 shows a schematic block diagram of a communication device 1100 provided in an embodiment of the present application.

[0124] FIG12 shows a schematic block diagram of another communication device 1200 provided in an embodiment of the present application.

[0125] FIG13 shows a schematic diagram of a chip system 1300 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0126] The technical solution in this application will be described below with reference to the accompanying drawings.

[0127] The technical solutions provided in this application can be applied to various communication systems, such as: fourth generation (4G) system, fifth generation (5G) or new radio (NR) system, long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD) system, etc. The technical solutions provided in this application can also be applied to future communication systems, such as the sixth generation mobile communication system. The technical solutions provided in this application can also be applied to device to device (D2D) communication, vehicle to everything (V2X) communication, machine to machine (M2M) communication, machine type communication (MTC), and Internet of Things (IoT) communication system or other communication systems.

[0128] The method based on homomorphic encryption provided in the embodiment of the present application can be applied to the fourth generation (4G) communication system, such as the long term evolution (LTE) communication system, and can also be applied to the fifth generation (5G) communication system, such as the 5G new radio (NR) communication system, or to various communication systems evolved after 5G, such as the sixth generation (6G) communication system. The method provided in the embodiment of the present application can also be applied to a Bluetooth system, a wireless WiFi system, a long range Internet of Things (LoRa) system, or a vehicle network system. The method provided in the embodiment of the present application can also be applied to a satellite communication system, wherein the satellite communication system can be integrated with the above-mentioned communication system.

[0129] To facilitate understanding of the embodiments of the present application, the application scenarios used in the present application are described using the communication system architecture shown in Figures 1-1 and 1-2 as an example.

[0130] Figure 1-1 is a schematic diagram illustrating a possible, non-limiting system. As shown in Figure 1-1 , communication system 1000 includes a radio access network (RAN) 100 and a core network (CN) 200. RAN 100 includes at least one network device (e.g., 110a and 110b in Figure 1-1 , collectively referred to as 110) and at least one terminal (e.g., 120a-120j in Figure 1-1 , collectively referred to as 120). RAN 100 may also include other RAN nodes, such as wireless relay devices and / or wireless backhaul devices (not shown in Figure 1-1). Terminal 120 is wirelessly connected to network device 110. Network device 110 is wirelessly or wiredly connected to core network 200. The core network devices in core network 200 and network device 110 in RAN 100 may be separate physical devices, or they may be a single physical device that integrates core network logical functions and radio access network logical functions.

[0131] The RAN 100 may be a cellular system related to the Third Generation Partnership Project (3GPP), such as a 4G or 5G mobile communication system, or an evolved system beyond 5G (such as a 6G mobile communication system). The RAN 100 may also be an open access network (O-RAN or ORAN), a cloud radio access network (CRAN), or a WiFi system. The RAN 100 may also be a communication system that integrates two or more of the above systems.

[0132] The apparatus provided in the embodiment of the present application can be applied to the network device 110 or to the terminal 120. It is understood that FIG1-1 only shows a possible communication system architecture to which the embodiment of the present application can be applied, and in other possible scenarios, the communication system architecture may also include other devices.

[0133] The network device 110 is a node in the radio access network (RAN), and can also be called an access network device or a RAN node (or device). The network device 110 is used to help terminals achieve wireless access. The multiple network devices 110 in the communication system 1000 can be nodes of the same type or different types. In some scenarios, the roles of the network device 110 and the terminal 120 are relative. For example, the network element 120i in Figure 1-1 can be a helicopter or a drone, which can be configured as a mobile base station. For the terminal 120j that accesses the RAN 100 through the network element 120i, the network element 120i is a base station; but for the base station 110a, the network element 120i is a terminal. The network device 110 and the terminal 120 are sometimes referred to as communication devices. For example, the network elements 110a and 110b in Figure 1-1 can be understood as communication devices with base station functions, and the network elements 120a-120j can be understood as communication devices with terminal functions.

[0134] In one possible scenario, a network device can be a base station, an evolved NodeB (eNodeB), a transmitting and receiving point (TRP), a transmitting point (TP), a next-generation NodeB (gNB), a next-generation base station in a sixth-generation (6G) mobile communication system, a base station in a future mobile communication system, a satellite, an access point (AP) in a WiFi system, an integrated access and backhaul (IAB) node, a mobile switching center, or a network device in a non-terrestrial network (NTN) communication system, i.e., it can be deployed on a high-altitude platform or satellite. The network device can be a macro base station (such as 110a in Figure 1-1), a micro base station or an indoor station (such as 110b in Figure 1-1), a relay node or a donor node, or a wireless controller in a CRAN scenario. The network device can also function as a base station in device-to-device (D2D) communication, vehicle-to-vehicle communication, drone communication, or machine communication. Optionally, the network device may also be a server, a wearable device, a vehicle or an onboard device, etc. For example, the access network device in vehicle to everything (V2X) technology may be a road side unit (RSU).

[0135] In another possible scenario, multiple network devices collaborate to assist the terminal in achieving wireless access, and different network devices respectively implement part of the functions of the base station. For example, the network device can be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and DU can be set separately, or can also be included in the same network element, such as a baseband unit (BBU). The RU can be included in a radio frequency device or a radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH). It can be understood that the network device can be a CU node, a DU node, or a device including a CU node and a DU node. In addition, the CU can be divided into a network device in the access network RAN, or the CU can be divided into a network device in the core network CN, which is not limited here.

[0136] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, in the ORAN system, CU may also be called O-CU (Open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, CU-UP may also be called O-CU-UP, and RU may also be called O-RU. For the convenience of description, this application uses CU, CU-CP, CU-UP, DU and RU as examples for description. Any unit of CU (or CU-CP, CU-UP), DU and RU in this application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0137] In the embodiments of the present application, the form of the network device is not limited. The device used to implement the function of the network device can be a network device; it can also be a device that can support the network device to implement the function, such as a chip system. The device can be installed in the network device or used in conjunction with the network device.

[0138] Terminal device 120, which may also be referred to as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., is a device used to provide voice or data connectivity to users, or an IoT device. For example, terminal devices include handheld devices with wireless connectivity, vehicle-mounted devices, etc. Currently, terminal devices can include: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MIDs), wearable devices (such as smart watches, smart bracelets, pedometers, etc.), vehicle-mounted devices (such as cars, bicycles, electric vehicles, airplanes, ships, trains, high-speed trains, etc.), satellite terminals, virtual reality (VR) devices, augmented reality (AR) devices, smart point-of-sale (POS) machines, customer-premises equipment (CPE), wireless terminals in industrial control, smart home devices (such as refrigerators, televisions, air conditioners, electricity meters, etc.), intelligent robots, robotic arms, workshop equipment, wireless terminals in unmanned driving, wireless terminals in telemedicine, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, and flying devices (such as intelligent robots, hot air balloons, drones, airplanes). Terminal devices can also be other devices with terminal functions, for example, terminal devices can also be devices that function as terminals in D2D communication.

[0139] The embodiments of this application do not limit the device form factor of the terminal. The device used to implement the functions of the terminal device can be the terminal device; it can also be a device that supports the terminal device to implement the functions, such as a chip system. The device can be installed in the terminal device or used in conjunction with the terminal device. In the embodiments of this application, the chip system can be composed of chips or include chips and other discrete devices.

[0140] Figure 1-2 shows a schematic diagram of a system architecture, more specifically, a wireless communication system and access network. As shown in Figure 1-2, the wireless communication system includes a core network (such as core network #1 and core network #2 in Figure 1-2), network devices (such as network device #1, network device #2, network device #3, and network device #4 in Figure 1-2), and terminal devices. A mobility management entity (MME) / serving gateway (S-GW) can connect to network devices.

[0141] For example, core network #1 may be a 4G evolved packet core network (EPC), network device #1 and network device #2 may be 4G base stations (e.g., evolutionary NodeB (eNB or eNodeB) in an LTE system); core network #2 may be a 5G core network (5GC), and network device #3 and network device #4 may be 5G base stations (e.g., next generation Node Base station (gNB)). Next generation control plane (NG-CP) / user plane gateway (NG-CP) The UPGW (update gateway) connects to the gNB via the Ng interface. eNBs are connected to each other via the X2 interface, eNBs are connected to gNBs via the X2 interface, gNBs are connected to each other via the Xn interface, and gNBs are connected to UEs via the Uu interface. For example, core network #1 may be a 5G core network, and network device #1 and network device #2 may be 5G base stations. Core network #2 may also be a 6G core network, and network device #3 and network device #4 may be 6G base stations. This application is not limited to this.

[0142] Base stations may include macro stations (high-power cellular base stations) and / or micro stations (low-power cellular base stations). Macro stations include macro cells, and micro stations include micro cells, pico cells, and femto cells. Base stations may also be referred to as xNBs, gNBs, Node Bs, evolved Node Bs (evolved NodeBs, eNBs), access points, base station transceivers, wireless base stations, wireless transceivers, transceiver functions, basic service sets (BSSs), extended service sets (ESSs), transmission reception points (TRPs), etc., and this application does not limit this.

[0143] The UE mainly accesses the 5G network and obtains services through the wireless air interface. The UE interacts with the radio access network (RAN) equipment through the air interface, and interacts with the access and mobility management function (AMF) network element of the core network through non-access stratum (NAS) signaling.

[0144] 4G base stations (eNBs) can connect to the 4G core network via the backhaul network (S1 interface). 5G base stations (gNBs) can connect to the 5G core network (5GC) via the backhaul network (Ng interface), or to the LTE EPC via the S1 interface. Base stations can perform one or more of the following functions: user data and control signaling transmission, encryption and decryption of user data or air interface signaling, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, paging, positioning and warning information delivery, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), user and device tracking, and RAN information management. Multiple base stations can communicate directly or indirectly with each other via the backhaul network (X2 and Xn interfaces). Base stations can wirelessly communicate with UEs. Base stations provide UEs with access points to the EPC or 5GC. Each base station can provide communication services to end users within its corresponding geographic coverage area.

[0145] As an example, a schematic diagram of a network architecture is shown in Figure 2. Below, in conjunction with Figure 2, a network architecture consisting of a 5G core network, access network, and data network (DN) is used as an example to introduce the network architecture applicable to this application.

[0146] As shown in Figure 2, the 5G core network may include a user plane function (UPF) network element, an authentication server function (AUSF) network element, an access and mobility management function (AMF) network element, a session management function (SMF) network element, a network exposure function (NEF) network element, a network function library function (NRF) network element, a policy control function (PCF) network element, a network slice selection function (NSSF) network element, a unified data management (UDM) network element and an application function (AF) network element.

[0147] UPF mainly provides user plane functions such as forwarding and processing of user messages, connection with DN, session anchor, and quality of service (QoS) policy execution. For example, UPF can receive user plane data from DN and send the user plane data to the terminal device through the RAN device. UPF can also receive user plane data from the terminal device through the RAN device and forward it to the DN. It should be understood that if the UE moves while performing business, the UPF remains unchanged to ensure business continuity. AUSF is mainly used for user authentication, etc. AMF is mainly used for access control, mobility management, attachment and detachment, etc. UDM is mainly used for UE subscription data management, including the storage and management of UE identification, UE access authorization, etc.

[0148] In the network architecture shown in Figure 2, network elements can communicate with each other through the interfaces shown in the figure. Some interfaces can be implemented as service-oriented interfaces. As shown in Figure 2, the SMF and UPF can communicate through the N4 interface. The UPF and DN can communicate through the N6 interface. The relationships between other interfaces and network elements are shown in Figure 2 and are not detailed here for the sake of brevity.

[0149] It should be understood that the network architecture shown above is only an exemplary illustration, and the network architecture applicable to the embodiments of the present application is not limited to this. Any network architecture that can realize the functions of the above-mentioned network elements is applicable to the embodiments of the present application.

[0150] It should also be understood that the functions or network elements shown in Figure 2 can be understood as network elements used to implement different functions, for example, they can be combined into network slices as needed. These network elements can be independent devices, or they can be integrated into the same device to implement different functions, or they can be network elements in hardware devices, or they can be software functions running on dedicated hardware, or they can be virtualized functions instantiated on a platform (for example, a cloud platform). This application does not limit the specific form of the above network elements.

[0151] It should also be understood that the above network elements or functions may be divided into one or more services, and further, there may be services that exist independently of the network functions. In this application, instances of the above functions, instances of services included in the above functions, or instances of services that exist independently of the network functions may all be referred to as service instances.

[0152] In the embodiment of the present application, the chip system can be composed of chips, or can include chips and other discrete devices.

[0153] It should also be understood that the above naming is defined only to facilitate the distinction between different functions and should not constitute any limitation to this application. This application does not exclude the possibility of adopting other naming in 6G networks and other future networks. For example, in a 6G network, some or all of the above network elements may continue to use the terminology used in 5G, or may adopt other names.

[0154] It should also be understood that the interface names between the various network elements in Figure 2 are merely examples, and in specific implementations, the interface names may be other names, which are not specifically limited in this application. In addition, the names of the messages (or signaling) transmitted between the various network elements are merely examples and do not constitute any limitation on the functions of the messages themselves.

[0155] To facilitate understanding of the embodiments of the present application, the following briefly describes the terms or technologies involved in the present application.

[0156] 1. Homomorphic encryption

[0157] Homomorphic encryption aims to perform computations on ciphertext without exposing the plaintext data. It focuses on privacy-preserving computation and is a technology that enables data value mining while maintaining privacy. Homomorphic encryption builds on basic encryption with the added capability of homomorphic computation. Homomorphic encryption allows computations to be performed directly on encrypted ciphertext, and the decrypted result is consistent with the plaintext result. Full homomorphism can be achieved using either asymmetric public-key or symmetric encryption, as long as the ciphertext has a certain algebraic structure.

[0158] Homomorphic participants (or homomorphic enablers) that perform homomorphic tasks (e.g., homomorphic encryption tasks) may include key generation, homomorphic encryption, homomorphic decryption, and homomorphic evaluation. The key generation is used to generate homomorphic keys (e.g., homomorphic encryption keys K enc , homomorphic decryption key K dec , homomorphically compute the key K eval ) and send them to the homomorphic encryption party, homomorphic decryption party and homomorphic calculation party respectively; the homomorphic encryption party is used to encrypt the plaintext into ciphertext according to the homomorphic encryption key; the homomorphic calculation party is used to perform homomorphic calculation on the ciphertext according to the homomorphic calculation key; the homomorphic decryption party is used to restore the ciphertext after homomorphic calculation to plaintext according to the homomorphic decryption key.

[0159] Specifically, the homomorphic (public key) encryption scheme HE=(HE.Keygen, HE.Enc, HE.Dec, HE.Eval) is composed of four algorithms, as shown below (where n is a security parameter):

[0160] (1) Key generation (HE.Keygen): (pk,evk,sk)←HE.Keygen(1 n ). Output the homomorphic encryption key K through the key generation algorithm enc =pk, homomorphic evaluation key K deval =evk, homomorphic decryption key K dec =sk.

[0161] (2) Homomorphic encryption (HE.Enc): c←HE.Enc pk (m). Using homomorphic encryption key K enc =pk, encrypt the single bit message m∈{0,1} into ciphertext c.

[0162] (3) Homomorphic decryption (HE.Dec): m←HE.Dec sk (c) Using the homomorphic decryption key K dec =sk, decrypt the ciphertext c and restore it to the message m∈{0,1}.

[0163] (4) Homomorphic computation (HE.Eval, also called homomorphic evaluation): c f ←HE.Eval evk (f,c1,…,c l ). Use homomorphic calculation key K eval =evk, and the function f∶{0,1}l →{0,1} applies to c1,…,c l , and output the ciphertext c f Here, f represents an arithmetic circuit with addition and multiplication gates on GF(2). Usually, the homomorphic computation HE.Eval is decomposed into the homomorphic addition c add ←HE.Add evk (c1,c2) ​​and homomorphic multiplication c mult ←HE.Mult evk (c1,c2).

[0164] After the above homomorphic encryption process, the ciphertext calculation result of the entire homomorphic encryption scheme HE = (HE.Keygen, HE.Enc, HE.Dec, HE.Eval) is equivalent to the plaintext calculation result after decryption, as shown below:

[0165] It should be understood that for a homomorphic task, there can be multiple homomorphic encryption parties to encrypt data from different sources; there can also be multiple homomorphic computing parties to perform homomorphic computing, or there can be single-hop or multi-hop homomorphic computing parties; there can also be multiple homomorphic decryption parties, which can give the decryption results to multiple data users, and so on. Depending on the key deployment situation, the homomorphic decryption party and the data user can be the same or different entities. The keys of multiple homomorphic participants in a homomorphic task (for example, a homomorphic encryption task) (for example, the keys of the homomorphic encryption party) can be the same or different. This application is not limited to this.

[0166] 2. Key Architecture

[0167] In the 5G system (5GS), taking the 5G authentication and key agreement protocol (5G AKA) as an example, the key architecture generated by the key hierarchy is shown in Figure 3. Among them, the keys related to identity authentication include K, CK (cipher key), IK (integrity key), and the key hierarchy includes the following keys in sequence: AUSF key (K AUSF ), anchor key (K SEAF ), AMF key (K AMF ), NAS signaling key (K NASint , K NASenc ), non-3GPP access key (K N3IWF ), NG-RAN key (K gNB ), the key transmitted by the UP user plane (K UPint , K UPenc ), RRC signaling key (K RRCint , K RRCenc ).

[0168] Specifically, in 5GS, security network elements (or network elements with root keys) include the UDM, AMF, AUSF, authentication credential repository and processing function (ARPF) network element, and security anchor function (SEAF) network element. The ARPF is primarily used to store user root keys and related authentication subscription data, and calculate the 5G authentication vector. The SEAF is primarily used to derive the underlying NAS and AS keys based on the anchor key, and to compare authentication results.

[0169] The following is a description of each of the above keys:

[0170] (1)K AUSF : K in the home network AUSF K is derived from CK and IK by mobile equipment (ME) and ARPF AUSF , K AUSF Received from the ARPF as part of the 5G home environment authentication vector (HE AV).

[0171] (2)K SEAF :ME and AUSF from K AUSF Derived anchor key. K AUSF Provided by AUSF to SEAF in the serving network.

[0172] (3)K AMF :K in service network AMF It is ME and SEAF from K SEAF Derived key. K AMF Further derived by the ME and the source AMF when performing horizontal key derivation.

[0173] (4)NAS signaling key: K NASint It is ME and AMF from K AMF The derived key that is used to protect NAS signaling using a specific integrity algorithm. K NASenc It is ME and AMF from K AMF The derived key is used to protect NAS signaling using a specific encryption algorithm.

[0174] (5)K N3IWF :K N3IWF It is ME and AMF from K AMFDerived key for non-3GPP access. K N3IWF Not forwarded between N3IWFs.

[0175] (6)K gNB :K gNB It is ME and AMF from K AMF Derived key. K gNB Further derived by the ME and source gNB when performing horizontal or vertical key derivation.

[0176] (7) User plane UP transmission key: K UPint ME and gNB from K gNB The key generated by the ME is used to protect the user plane data between the ME and the gNB using a specific integrity algorithm. UPenc ME and gNB from K gNB The derived key is used to protect data transmitted by UP using a specific encryption algorithm.

[0177] (8)RRC signaling key: K RRCint ME and gNB from K gNB A derived key used to protect RRC signaling using a specific integrity algorithm. RRCenc ME and gNB from K gNB A derived key that is used to protect RRC signaling using a specific encryption algorithm.

[0178] It should be understood that when deriving new keys from a secret key, a key derivation function (KDF) may be used. A key derivation function is a function that uses a pseudo-random function to derive one or more keys from a master key. A key derivation function can extend a key to a longer key or obtain a key in a desired format.

[0179] It should be understood that the term "and / or" in this document simply describes an association between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0180] The above describes the network architecture applicable to this application. The following describes in detail the communication method based on homomorphic encryption provided by the embodiment of this application in conjunction with the accompanying drawings. The embodiment provided by this application can be applied to the network architecture shown in Figures 1 and 2 above, without limitation.

[0181] With the advancement of society and the growing awareness of data ownership, the demand for data privacy protection is becoming increasingly stringent. To improve data security and privacy, homomorphic encryption technology can be used to perform computations on ciphertext without exposing the plaintext data, thereby enabling data value mining while maintaining privacy. Terminal devices, base stations, network elements, and other devices in wireless communication networks (such as the network architectures in Figures 1 and 2) can also participate in homomorphic tasks as homomorphic participants (homomorphic encryptors, homomorphic decryptors, homomorphic computations, key generators, etc.). For example, smart cars, smartphones, and VR / AR terminals equipped with on-board units (OBUs) possess homomorphic encryption capabilities. When privacy protection is required, sensitive data is encrypted and then transmitted to other terminal nodes, roadside units (RSUs), base stations, core network functions (NFs), cloud providers, and other nodes within the communication network for homomorphic computation under ciphertext. The resulting ciphertext data is then transmitted to the data user for homomorphic decryption and use.

[0182] However, since nodes such as base stations and core network elements need to perceive the communication and computing resource status of the homomorphic participants in the homomorphic task in real time and coordinate the control of communication and computing resources, they can ensure that homomorphic privacy protection services that meet QoS requirements such as ultra-low latency, high data security and privacy, and sustainability are provided in dynamic and complex wireless network environments. When the information related to the homomorphic task changes (for example, the homomorphic key changes, the homomorphic participants change, etc.), the homomorphic task may be interrupted.

[0183] This application proposes a communication method based on homomorphic encryption, which can solve the problem of homomorphic task interruption caused by changes in homomorphic task-related information during the execution of the homomorphic task, thereby ensuring the continuity of the homomorphic task.

[0184] Based on the network architecture of Figures 1 and 2 above, a communication method 400 based on homomorphic encryption provided by this application is introduced in detail below in combination with Figure 4.

[0185] Figure 4 is a schematic diagram of a communication method 400 based on homomorphic encryption provided by an embodiment of the present application. When the root key of the network device (core network or base station) to which the terminal device accesses is updated, for example, the terminal device undergoes a mobility management related process, which causes the root key of the network device to which the terminal device accesses to be updated (such as the network device to which the terminal device accesses is switched, causing the root key of the network device to be updated), or the network device to which the terminal device accesses is not switched but the root key of the network device is updated, etc., it is necessary to re-derive the homomorphic key based on the updated root key to ensure the continuity of the homomorphic task. Method 400 is described in detail below in conjunction with Figure 4.

[0186] It should be understood that the relevant processes for mobility management of the above-mentioned terminals may be in a mobile communication system (for example, a mobile cellular network), where an idle terminal device (or mobile device) performs cell selection, cell reselection, mobility registration update, etc., a connected terminal device performs cell switching, etc., an inactive terminal device performs cell reselection, terminal device triggering or periodically triggering RAN-based notification area (RNA) update, state migration, etc., and this application is not limited to this.

[0187] S410: The key generator obtains a first key parameter.

[0188] Among them, the first key parameter is the key parameter of the updated root key of the network device to which the terminal device accesses.

[0189] Exemplarily, the first key parameter is the root key of the base station or core network element under the USIM key architecture. The first key parameter may also be a parameter used to generate the root key of the base station or core network element under the USIM key architecture.

[0190] The key generator is the device that derives the homomorphic key in the homomorphic task. Specifically, the key generator can be a core network element, a base station, a homomorphic encryption control function (HECF), a terminal device, etc., and this application does not limit this.

[0191] Among them, HECF can perform key management of homomorphic tasks (for example, derivation and distribution of homomorphic keys, update and management of homomorphic keys, etc.), capability management of homomorphic tasks (for example, generation and storage of homomorphic capability lists), homomorphic task management (for example, homomorphic task request management, homomorphic task scheduling management, etc.), etc., and this application does not limit this.

[0192] It should be understood that the root key of the network device to which the terminal device is connected is the superior key of the homomorphic key in the homomorphic task. In the homomorphic task, when the superior key of the homomorphic key is updated, if the homomorphic key is not re-derived, it may cause the homomorphic task to be interrupted. Therefore, it is necessary to re-derive the homomorphic key based on the updated root key of the first network device (i.e., the first key parameter). Further, method 400 also includes S420.

[0193] S420: The key generator derives a homomorphic encryption and decryption key based on the first key parameter and the homomorphic encryption and decryption algorithm.

[0194] Among them, the homomorphic encryption and decryption keys are used for homomorphic tasks in which terminal devices participate. The homomorphic encryption and decryption keys include homomorphic encryption keys and homomorphic decryption keys, and the homomorphic encryption keys and homomorphic decryption keys are corresponding.

[0195] In one possible implementation, the key generator derives the homomorphic encryption and decryption key based on the first key parameter, the homomorphic encryption and decryption algorithm, and the second key parameter.

[0196] The second key parameter and the homomorphic encryption and decryption algorithm are determined based on the homomorphic capability information of the terminal device and / or the homomorphic capability information of the third network device.

[0197] It should be understood that the key generator needs to determine the second key parameters and homomorphic encryption and decryption algorithm used to generate homomorphic encryption and decryption keys based on the homomorphic capability information of the homomorphic participants (terminal devices and other devices participating in homomorphic tasks), so that the generated homomorphic encryption and decryption keys can be applied to homomorphic tasks.

[0198] Among them, the third network device is a device participating in the homomorphic task (or homomorphic participant). The third network device can be one or more devices participating in the homomorphic task, and this application is not limited to this. In other words, the second key parameter and the homomorphic encryption and decryption algorithm are determined based on the homomorphic capabilities of one or more devices (homomorphic participants) participating in the homomorphic task.

[0199] Specifically, the homomorphic capability information includes at least one of the following: homomorphic capability type, homomorphic encryption and decryption algorithm identifier, homomorphic calculation function identifier, security level λ, decryption circuit depth d, and complexity of the ciphertext calculation circuit.

[0200] Specifically, the second key parameter includes at least one of the following: an identifier of the homomorphic encryption and decryption algorithm, a ciphertext modulus, a plaintext modulus, and a polynomial dimension.

[0201] The identifier of the homomorphic encryption and decryption algorithm is used to indicate the algorithm for deriving the homomorphic encryption and decryption key.

[0202] In one possible implementation, the key generator obtains information about the homomorphic task requirements. When the key generator determines that the third network device meets the homomorphic task requirements, the key generator derives the homomorphic encryption and decryption key based on the first key parameter, the homomorphic encryption and decryption algorithm, and the homomorphic task requirements.

[0203] It should be understood that the key generator will derive homomorphic encryption and decryption keys only when the device participating in the homomorphic task (third network device) requires the homomorphic task. This avoids unnecessary key derivation and can save resources.

[0204] Homomorphic task requirements are used to indicate the parameters required to execute a homomorphic task. Specifically, homomorphic task requirements include homomorphic task type, homomorphic task quality, number of homomorphic encryptors, homomorphic encryptor parameters, number of homomorphic users, and homomorphic user parameters.

[0205] It should be understood that the key generator can receive homomorphic task requirements from other homomorphic participants, or when the key generator is in a homomorphic task and the root key of the network device to which the terminal device is connected is updated, the key generator itself is aware of the homomorphic task requirements. This application does not limit the way in which the key generator obtains the homomorphic task requirements.

[0206] Based on the above scheme, in the communication system, when the superior key of the homomorphic key corresponding to the homomorphic task in which the terminal device participates changes, the key generator can re-derive the homomorphic key used for the homomorphic task based on the superior key of the updated homomorphic encryption and decryption key (the root key of the network device to which the terminal device accesses), thereby ensuring the continuity of the homomorphic task of the terminal device.

[0207] In one possible implementation, after the key generator derives the homomorphic encryption and decryption key, the key generator sends the homomorphic encryption and decryption key to the homomorphic encryption party and the homomorphic decryption party.

[0208] In one possible implementation, after the key generator derives the homomorphic encryption and decryption key, the key generator derives the homomorphic computing key based on the homomorphic encryption and decryption key, and sends the homomorphic computing key to the homomorphic computing party.

[0209] Specifically, when the key generator is a different device, the key generator obtains the first key parameter in different ways. The following describes the specific process of the key generator obtaining the first key parameter when the key generator is a first network device, HECF, and terminal device.

[0210] Case 1: The key generator is the first network device, which can be a core network element (for example, AMF) or a base station, etc. This application does not limit this.

[0211] At this time, the key generator in S410 may obtain the first key parameter in the following manners.

[0212] In a possible implementation, the first network device receives the first key parameter from the second network device, wherein the second network device is the network device to which the terminal device accesses before the handover, and the first network device is the network device to which the terminal device accesses after the handover.

[0213] It should be understood that when the root key of the network device to which the terminal device is connected is updated due to switching of the network device to which the terminal device is connected, the network device before the terminal device is switched (the second network device) sends the updated root key to the network device after the terminal device is switched (the first network device).

[0214] Exemplarily, when the network device accessed by the terminal device switches from the second network device (eg, source base station) to the first network device (eg, target base station), the first network device receives the first key parameter sent from the second network device.

[0215] It should be understood that the second network device derives and updates the first key parameters corresponding to the first network device in the mobility management process. When the network device to which the terminal device is connected switches, the second network device sends the first key parameters to the first network device to derive a new homomorphic key.

[0216] In a possible implementation manner, a first network device generates a first key parameter, and the first network device is a network device to which the terminal device accesses.

[0217] Exemplarily, when the network device to which the terminal device is connected has not changed but the root key of the network device has been updated, the key generator generates a first key parameter. For example, in a state transition process, such as the state transition between the RM deregistration state (RM-DEREGISTERED) and the RM registration state (RM-REGISTERED) in registration management (RM), or the CM idle state (CM-IDLE) and the CM connected state (CM-CONNECTED) in connection management (CM), if there is no complete local 5G NAS security context available from the AMF (i.e., the terminal device sends an unprotected registration request message, or the terminal device protects the registration request message using the current local 5G security context that is no longer stored in the AMF), a primary authentication operation is required. If a complete native 5G NAS security context is available in the AMF, the AMF may (according to the AMF policy) decide to run a new primary authentication and NAS SMC process after the registration request (which is based on the K derived during the primary authentication operation). AMFActivate new 5G NAS security context).

[0218] It should be understood that before deriving the homomorphic key (ie, before S420 ), it is necessary to determine the homomorphic encryption and decryption algorithm used to derive the homomorphic key.

[0219] For case 1, when the key generator is the first network device, the homomorphic encryption and decryption algorithm can be determined by the first network device, or the HECF can determine the homomorphic encryption and decryption algorithm and indicate it to the first network device.

[0220] Specifically, when the first network device determines the homomorphic encryption and decryption algorithm, method 400 may further include S430 - S432 .

[0221] S430: The first network device receives homomorphic capability information of the terminal device.

[0222] In a possible implementation, the terminal device sends homomorphic capability information of the terminal device to the first network device.

[0223] S431: The first network device determines a homomorphic encryption and decryption algorithm according to the homomorphic capability information of the terminal device.

[0224] In one possible implementation, when the first network device receives homomorphic capability information of the third network device, the first network device determines a homomorphic encryption and decryption algorithm based on the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device.

[0225] Among them, the third network device is a device that participates in executing the homomorphic task.

[0226] Optionally, the first network device may determine the second key parameter according to the homomorphic capability information of the terminal device (and / or the homomorphic capability information of the third network device).

[0227] S432: The first network device sends first indication information to the terminal device.

[0228] Correspondingly, the terminal device receives the first indication information from the first network device.

[0229] The first indication information is used to indicate the identifier of the homomorphic encryption and decryption algorithm.

[0230] Optionally, when the first network device determines the second key parameter in S431, the first indication information is further used to indicate the second key parameter.

[0231] In one possible implementation, the first indication information is sent to the terminal device via NAS signaling.

[0232] Specifically, when the HECF determines the homomorphic encryption and decryption algorithm and indicates it to the first network device, the method 400 may further include S433.

[0233] S433: The first network device receives an identifier of the homomorphic encryption and decryption algorithm from the HECF.

[0234] Specifically, HECF determines the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device (and / or the homomorphic capability information of the third network device), and sends the identifier of the homomorphic encryption and decryption algorithm to the first network device, so that the first network device derives the homomorphic encryption and decryption key according to the corresponding homomorphic encryption and decryption algorithm.

[0235] Case 2: The key generator is HECF, or the key generator is other devices with specific homomorphic management capabilities, etc. This application is not limited to this. For example, in the scenario of homomorphic tasks and centralized key management, HECF acts as the key generator and derives the homomorphic key corresponding to the homomorphic task.

[0236] At this time, the key generator in S410 may obtain the first key parameter in the following manners.

[0237] In one possible implementation, the HECF generates a first key parameter.

[0238] Exemplarily, when a terminal device undergoes a mobility management process, the terminal device sends an indication message to HECF, indicating that the network device to which the terminal device is connected is switched, and then HECF generates an updated root key of the network device to which the terminal device is connected, i.e., a first key parameter, based on the indication message.

[0239] It should be understood that for case 2, when the key generator is HECF, the homomorphic encryption and decryption algorithm is determined by HECF, and method 400 may further include S440-S441.

[0240] S440 , the HECF receives homomorphic capability information of the terminal device.

[0241] In one possible implementation, the terminal device sends homomorphic capability information of the terminal device to the HECF.

[0242] S441, HECF determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the terminal device.

[0243] In one possible implementation, when the HECF receives the homomorphic capability information of the third network device, the HECF determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device.

[0244] Among them, the third network device is a device that participates in executing the homomorphic task.

[0245] Optionally, the HECF may determine the second key parameter based on the homomorphic capability information of the terminal device (and / or the homomorphic capability information of the third network device).

[0246] It should be understood that when the key generator is HECF, after HECF derives the homomorphic encryption and decryption key in S420, it sends the derived homomorphic encryption and decryption key to the homomorphic participants (homomorphic encryption party and homomorphic decryption party), and method 400 can also include S442.

[0247] S442, HECF sends the homomorphic encryption and decryption key to the first network device and the terminal device.

[0248] Among them, the first network device is a network device to which the terminal device accesses.

[0249] In one possible implementation, for a homomorphic task, the first network device acts as the homomorphic encryption party, and the terminal device acts as the homomorphic decryption party.

[0250] Case 3: The key generator is the terminal device.

[0251] For example, in the USIM key architecture scenario, the terminal device can act as a key generator to derive the homomorphic key corresponding to the homomorphic task.

[0252] At this time, the key generator in S410 may obtain the first key parameter in the following manners.

[0253] In a possible implementation manner, the terminal device receives second indication information from the first network device, and the terminal device generates a first key parameter according to the second indication information.

[0254] The second indication information is used to indicate that a root key of a network device to which the terminal device accesses is updated, and the first network device is the network device to which the terminal device accesses.

[0255] Specifically, the terminal device learns, based on the received second indication information, that the root key of the network device to which the terminal device is connected has been updated, and then generates the first key parameter.

[0256] In a possible implementation manner, the second indication information is sent by the key generator to the terminal device through NAS security mode signaling in the mobility registration update process or switching signaling in the cell switching process.

[0257] It should be understood that for case three, when the key generator is a terminal device, the first network device or HECF determines the homomorphic encryption and decryption algorithm and indicates it to the terminal device, and method 400 may further include S450.

[0258] S450, the terminal device receives an identifier of the homomorphic encryption and decryption algorithm from the first network device or the HECF.

[0259] Specifically, the first network device or HECF determines the homomorphic encryption and decryption algorithm based on the homomorphic capability information of the terminal device (and / or the homomorphic capability information of the third network device), and sends the identifier of the homomorphic encryption and decryption algorithm to the terminal device, so that the terminal device derives the homomorphic encryption and decryption key according to the corresponding homomorphic encryption and decryption algorithm.

[0260] The above, combined with Figure 4, illustrates the process by which the key generator re-derives the homomorphic encryption and decryption key when the root key of the network device to which the terminal device is connected changes. Based on Figure 4, the following, combined with Figures 5-7, illustrates in detail the process by which the key generator re-derives the homomorphic encryption and decryption key when the root key of the network device to which the terminal device is connected changes in different scenarios.

[0261] Figure 5 is a schematic diagram of a communication method 500 based on homomorphic encryption provided by an embodiment of the present application. In a homomorphic task, if a homomorphic participant changes, such as when a terminal device switches (moves) in an idle state, if it determines that the currently accessed tracking area is not included in the registration area previously provided by the AMF, it will initiate a mobility registration update process to indicate the location change on the network side. At this time, the homomorphic encryption party or the homomorphic decryption party changes from the old AMF to the new AMF, so that the superior key of the homomorphic encryption and decryption key (such as K AMF ) has also changed, so the homomorphic key needs to be re-derived to ensure the continuity of the homomorphic task. Exemplarily, for AI application scenarios, the first AMF is the key generator and homomorphic encryption party on the network side, which encrypts the AI ​​data or model, the base station performs homomorphic calculations as the homomorphic calculation party, and the terminal device decrypts the ciphertext as the homomorphic decryption party. Exemplarily, for AI application scenarios, the terminal device acts as the key generator and homomorphic encryption party to encrypt the AI ​​data or model, the base station or roadside station performs homomorphic calculations as the homomorphic calculation party, and the first AMF decrypts the ciphertext as the homomorphic decryption party. The following is a detailed description of method 500 based on Figure 4 and combined with Figure 5.

[0262] S501: A terminal device sends a first registration request message to an access node. Correspondingly, the access node receives the first registration request message from the terminal device. Exemplarily, the access node may be a RAN node.

[0263] The first registration request information is used to request registration of the terminal device.

[0264] It should be understood that when the terminal device moves in the idle state, if it determines that the currently accessed tracking area is not included in the registration area previously provided by the AMF, it will initiate a mobility registration update process to request re-registration of the terminal device.

[0265] S502: The access node selects an AMF.

[0266] It should be understood that after the access node receives the first registration request information of the terminal device, it selects a new AMF for the terminal device. For ease of description, the new AMF selected by the access node is referred to as the first AMF, and the AMF accessed by the terminal device before switching is referred to as the second AMF.

[0267] S503: The access node sends a second registration request message to the first AMF.

[0268] Correspondingly, the first AMF receives a second registration request message from the access node.

[0269] The second registration request information is used to request the first AMF to register the terminal device.

[0270] S504: The first AMF sends a terminal device context forwarding request message to the second AMF.

[0271] Correspondingly, the second AMF receives the terminal device context forwarding request information from the first AMF.

[0272] S505: The second AMF sends a terminal device context forwarding response message to the first AMF.

[0273] The terminal device context forwarding response information includes the first K AMF , the first K AMF The root key of the first AMF that is newly generated or updated.

[0274] It should be understood that the first K AMF It can be the first key parameter in S410, that is, the key parameter related to the root key of the new AMF (first AMF) to which the terminal device is about to access.

[0275] S506: Authenticate the terminal device.

[0276] It should be noted that the authentication of the terminal device can refer to the description of the existing technology, and this application does not limit this.

[0277] S507: The first AMF sends a key change indication to the terminal device.

[0278] The key change indication is used to indicate that the root key of the first AMF is updated.

[0279] It should be understood that the key change indication may be the second indication information in S430.

[0280] Exemplarily, the key change indication may include a flag. When flag=1, the key change indication is used to indicate that the root key of the first AMF is updated; when flag=0, the key change indication is used to indicate that the root key of the first AMF is not updated.

[0281] In one possible implementation, the first AMF sends a NAS security mode command to the terminal device, where the NAS security mode command includes a key change indication.

[0282] S508: The terminal device generates the first K AMF .

[0283] For example, after the terminal device receives the key change indication, when flag=1, the terminal device learns that the root key of the network device to which the terminal device is connected has changed. Further, the terminal device generates the root key of the network device to which the terminal device is newly connected according to the preset protocol, that is, the first K AMF .

[0284] Furthermore, when the root key of the network device to which the terminal device is connected changes (updated to the first K AMF ) when the first K AMF Re-determine the homomorphic encryption and decryption algorithm and re-derive the homomorphic key. Depending on the entity that determines the homomorphic encryption and decryption algorithm and derives the homomorphic key, there are the following situations:

[0285] Case 1: The first AMF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key.

[0286] Case 2: The HECF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key.

[0287] Case 3: HECF determines the homomorphic encryption and decryption algorithm and derives the homomorphic key.

[0288] The above three situations are further described in detail below with reference to FIG. 5 .

[0289] Case 1: The first AMF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key. That is, at this time, the first AMF acts as both the homomorphic encryptor and the key generator on the network side, and the terminal device acts as both the homomorphic decryptor and the key generator on the terminal side. Method 500 may also include S509-S517.

[0290] S509: The access node sends its homomorphic capability information to the first AMF. Accordingly, the first AMF receives the homomorphic capability information from the access node.

[0291] The homomorphic capability information indicates the ability to perform homomorphic encryption and decryption or homomorphic computation. Specifically, the homomorphic capability information includes at least one of the following: homomorphic capability type, homomorphic encryption and decryption algorithm identifier, homomorphic computation function identifier, security level λ, decryption circuit depth d, and ciphertext computation circuit complexity.

[0292] Homomorphism types include at least one of the following: partially homomorphic, somewhat homomorphic, leveled homomorphic, and fully homomorphic. Specifically, partially homomorphic supports addition or multiplication; somewhat homomorphic supports addition and multiplication, but with a limited computational depth; leveled homomorphic supports computations of arbitrary polynomial depth; and fully homomorphic supports computations of arbitrary depth.

[0293] The homomorphic encryption and decryption algorithm identifier includes at least one of the following: additive homomorphic identifier (Paillier), multiplicative homomorphic identifier (Elgamal), multiplicative homomorphic identifier (Rivers Shamir Adleman, RSA), quasi-homomorphic identifier (BGN 05), BGV (without bootstrapping: hierarchical homomorphism; with bootstrapping: full homomorphism), BFV, CKKS, TFHE, etc., which are not limited in this application.

[0294] The homomorphic computing function identifier includes at least one of the following: convolutional neural network (CNN), recurrent neural network (RNN), generative adversarial network (GAN), support vector machine (SVM), etc., which is not limited in this application.

[0295] The security level λ is a parameter related to the security strength that the homomorphic encryption algorithm can provide.

[0296] The decryption circuit depth d indicates the computational complexity of the homomorphic decryption circuit.

[0297] The complexity of the ciphertext computation circuit may include the number of basic operators and the homomorphic computation depth L.

[0298] It should be understood that the above homomorphic capability information is only an example, and homomorphic capability may also include other information, which is not limited in this application. It should also be understood that the various information included in the above homomorphic capability can be randomly combined into a specified parameter set, which is not limited in this application.

[0299] It should be understood that the access node at this time may be the second network device in S420. It should be understood that the second network device should be a network device participating in the homomorphic task.

[0300] S510: The terminal device sends homomorphic capability information of the terminal device to the first AMF. Correspondingly, the first AMF receives the homomorphic capability information from the terminal device.

[0301] The homomorphic capability information of the terminal device can refer to the relevant description of the homomorphic capability information in S509 above, which will not be repeated here.

[0302] S511: The first AMF determines the homomorphic encryption and decryption algorithm and key derivation parameters.

[0303] Specifically, the first AMF determines the homomorphic encryption and decryption algorithm and key derivation parameters based on the homomorphic capability information of the access node in S509 and the homomorphic capability information of the terminal device in S510.

[0304] The key derivation parameter is the second key parameter in S420.

[0305] S512: The first AMF derives a new homomorphic encryption and decryption key.

[0306] Specifically, the first AMF is based on the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive a new homomorphic encryption and decryption key (K enc new ).

[0307] S513: The first AMF derives a new homomorphic computation key.

[0308] Specifically, the first AMF derives a new homomorphic computing key based on the homomorphic encryption and decryption key.

[0309] S514, the first AMF sends first indication information to the terminal device.

[0310] Correspondingly, the terminal device receives the first indication information from the first AMF.

[0311] Among them, the first indication information is used to indicate the identifier and key derivation parameters of the homomorphic encryption and decryption algorithm, so that the terminal device generates the corresponding homomorphic encryption and decryption key according to the first indication information.

[0312] S515, the terminal device derives a new homomorphic encryption and decryption key.

[0313] Specifically, the terminal device generates a signal according to the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive a new homomorphic encryption and decryption key (K enc new ).

[0314] S516: The terminal device derives a new homomorphic computing key.

[0315] Specifically, the terminal device derives a new homomorphic computing key based on the homomorphic encryption and decryption key.

[0316] It should be noted that this application does not limit the order of S512-S513 and S514-S516.

[0317] S517: The first AMF sends information about the homomorphic computing key and the homomorphic task to the access node.

[0318] Accordingly, the access node receives information about the homomorphic computation key and the homomorphic task from the first AMF.

[0319] It should be understood that at this time, the access node acts as a homomorphic computing party, receiving the homomorphic computing key and homomorphic task information from the first AMF to perform homomorphic computing.

[0320] Specifically, the information of the homomorphic task includes at least one of the following: homomorphic task role, homomorphic computing key K eval , homomorphic computation key size, ciphertext modulus q, plaintext modulus t, upper limit B of noise distribution, number of decimal places corresponding to computational precision, ciphertext computation vector dimension n, homomorphic encryption algorithm identifier, homomorphic computation function identifier. Among them, homomorphic task roles can be homomorphic encryption party, homomorphic computation party, homomorphic decryption party, etc. Homomorphic computation key K eval It can be a bootstrap key (BSK) or a key conversion key (KSK), etc.

[0321] In one possible implementation, the information of the homomorphic task may be sent in the form of a homomorphic task configuration message, and the parameters of the homomorphic task configuration message may be as shown in Table 1.

[0322] Table 1 Parameters of homomorphic task configuration message

[0323] Case 2: The HECF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key. That is, at this time, the first AMF acts as both the homomorphic encryption party and the key generator on the network side, and the terminal device acts as both the homomorphic decryption party and the key generator on the terminal side. Method 500 may also include S518-S526.

[0324] S518: The access node sends the homomorphic capability information of the access node to the HECF. Correspondingly, the HECF receives the homomorphic capability information from the access node.

[0325] It should be understood that the access node at this time may be the second network device in S420. It should be understood that the second network device should be a network device participating in the homomorphic task.

[0326] S519: The terminal device sends the homomorphic capability information of the terminal device to the HECF. Correspondingly, the HECF receives the homomorphic capability information from the terminal device.

[0327] For the description of the above homomorphic capability information, reference may be made to the related description of the homomorphic capability information in S509 , which will not be repeated here.

[0328] S520, HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters.

[0329] Specifically, the HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters according to the homomorphic capability information of the access node in S518 and the homomorphic capability information of the terminal device in S519.

[0330] The key derivation parameter is the second key parameter in S420.

[0331] S521, HECF sends first indication information.

[0332] Specifically, the HECF sends first indication information to the first AMF and the terminal device respectively, wherein the first indication information is used to indicate the identifier and key derivation parameters of the homomorphic encryption and decryption algorithm.

[0333] Furthermore, the first AMF and the terminal device derive a homomorphic key based on the homomorphic encryption and decryption algorithm and the key derivation parameters.

[0334] S522: The first AMF derives a new homomorphic encryption and decryption key.

[0335] Specifically, the first AMF is based on the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0336] S523: The first AMF derives a new homomorphic computation key.

[0337] Specifically, the first AMF homomorphic encryption and decryption key derives a new homomorphic computing key.

[0338] S524, the terminal device derives a new homomorphic encryption and decryption key.

[0339] Specifically, the terminal device generates a signal according to the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0340] S525, the terminal device derives a new homomorphic computing key.

[0341] Specifically, the terminal device derives a new homomorphic computing key from the homomorphic encryption and decryption key.

[0342] It should be noted that this application does not limit the order of S522-S523 and S524-S526.

[0343] S526: The first AMF sends the homomorphic computation key and homomorphic task information to the access node. Correspondingly, the access node receives the homomorphic computation key and homomorphic task information from the first AMF.

[0344] It should be understood that at this time, the access node acts as a homomorphic computing party, receiving the homomorphic computing key and homomorphic task information from the first AMF to perform homomorphic computing.

[0345] For the description of the above-mentioned homomorphic task information, please refer to the relevant description of the homomorphic task information in S517, which will not be repeated here.

[0346] Case 3: HECF determines the homomorphic encryption and decryption algorithm and derives the homomorphic key. In this case, it can be understood that the key generator is HECF, and HECF sends the generated homomorphic key to the homomorphic encryption party, homomorphic decryption party and homomorphic calculation party respectively. Method 500 can also include S527-S532.

[0347] S527: The access node sends the homomorphic capability information of the access node to the HECF. Correspondingly, the HECF receives the homomorphic capability information from the access node.

[0348] It should be understood that the access node at this time may be the second network device in S420. The second network device is a network device participating in the homomorphic task.

[0349] S528: The terminal device sends the homomorphic capability information of the terminal device to the HECF. Correspondingly, the HECF receives the homomorphic capability information from the terminal device.

[0350] For the description of the above homomorphic capability information, reference may be made to the related description of the homomorphic capability information in S509 , which will not be repeated here.

[0351] S529, HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters.

[0352] Specifically, the HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters according to the homomorphic capability information of the access node in S527 and the homomorphic capability information of the terminal device in S528.

[0353] The key derivation parameter may be the second key parameter in S420.

[0354] S530, HECF derives a new homomorphic encryption and decryption key.

[0355] Specifically, HECF is based on the first K AMF, homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0356] S531: HECF derives a new homomorphic computing key. Specifically, the HECF homomorphic encryption and decryption key derives a new homomorphic computing key.

[0357] S532, HECF sends the homomorphic key.

[0358] Specifically, HECF sends the homomorphic encryption key to the first AMF (homomorphic encryption party), sends the homomorphic decryption key to the terminal device (homomorphic decryption party), and sends the homomorphic computing key and homomorphic task information to the access node (homomorphic computing party).

[0359] For the description of the above-mentioned homomorphic task information, please refer to the relevant description of the homomorphic task information in S517, which will not be repeated here.

[0360] Optionally, in S540, the terminal device sends a completion message to the first AMF. Correspondingly, the first AMF receives the completion message from the terminal device.

[0361] In one possible implementation, the completion information is used to indicate that the NAS security mode is completed.

[0362] Based on the above scheme, in the mobility registration update process of the mobility management process, when the terminal device is switched and the superior key of the homomorphic key of the homomorphic task corresponding to the terminal device is updated, the homomorphic key can be re-derived in time according to the superior key of the updated homomorphic key, thereby ensuring the continuity of the homomorphic task of the terminal device during the switching process.

[0363] Figure 6 is a schematic diagram of a communication method 600 based on homomorphic encryption provided by an embodiment of the present application. The method is applicable to scenarios where the access node accessed by the terminal device and the corresponding core network network functions have changed. In a homomorphic task, if the homomorphic participants change, such as when the connected terminal device switches from the source base station (corresponding to the source cell) to the target base station (corresponding to the target cell), the reference signal received power (RSRP) of the source base station becomes weaker and weaker, and the RSRP of the target base station becomes stronger and stronger, and there is no Xn link between the base stations where the switching source cell and the target cell are located (or there is no Xn link between the source base station and the target base station), then the homomorphic encryption party or the homomorphic decryption party changes from the old network function (such as the old AMF) to the new network function (such as the new AMF), the homomorphic key generation party changes from the old network function (such as the old AMF) to the new network function (such as the new AMF), and the homomorphic calculation party changes from the source base station to the target base station, so that the superior key (such as KAMF) of the homomorphic encryption and decryption key also changes, so it is necessary to re-derive the homomorphic key to ensure the continuity of the homomorphic task. Exemplarily, for AI application scenarios, the first AMF acts as the key generator and homomorphic encryption party on the network side to encrypt the AI ​​model or data, and the terminal device acts as the homomorphic decryption party to decrypt the ciphertext. Exemplarily, for AI application scenarios, the terminal device acts as the key generator and homomorphic encryption party to encrypt the AI ​​model or data, and the first AMF acts as the homomorphic decryption party to decrypt the ciphertext. The following is a detailed description of method 600 based on Figures 4 and 5, combined with Figure 6.

[0364] S601: The source base station makes a handover decision.

[0365] It should be understood that when a connected terminal device switches from a source base station (corresponding to a source cell) to a target base station (corresponding to a target cell), the RSRP of the source base station becomes weaker and weaker, and the RSRP of the target base station becomes stronger and stronger. There is no Xn link between the base stations where the source cell and the target cell are located (or there is no Xn link between the source base station and the target base station). The source base station determines that a base station switch is required through a switching decision.

[0366] Specifically, the source base station may refer to the existing technology for handover decision, and this application does not limit this.

[0367] S602: The source base station sends a handover request message to the second AMF.

[0368] Correspondingly, the second AMF receives the handover request information from the source base station.

[0369] It should be understood that the source base station sends a handover request message to the source NF of the terminal device (or the access node (e.g., RAN) under the coverage of the source NF). This application does not limit the source NF. For ease of description, in this embodiment, the NF is taken as an example, that is, the source NF corresponding to the source base station is the second AMF.

[0370] The handover request information is used to indicate that a base station handover is required. For example, the handover request information may be HandOver Required.

[0371] S603: The second AMF determines the first AMF.

[0372] Specifically, after receiving the handover request information, the second AMF selects a target AMF to which handover can be performed. For ease of description, the target AMF is referred to as the first AMF.

[0373] S604: The second AMF sends a Create Terminal Device Context request to the first AMF. Correspondingly, the first AMF receives the Create Terminal Device Context request from the second AMF.

[0374] The request information for creating a terminal device context includes the first K AMF and homomorphic task requirements.

[0375] Specifically, the first K AMF It is the root key of the target AMF (i.e., the first AMF) that is newly generated or newly accessed by the terminal device.

[0376] It should be understood that since the terminal device switches from the source station to the target station, that is, switches from the second AMF to the first AMF, at this time, it can be understood that the root key of the network device accessed by the terminal device has been updated, that is, the root key of the network device accessed by the terminal device is updated from the root key of the second AMF to the root key of the first AMF. It should be understood that the first K AMF It can be the first key parameter in S410.

[0377] Specifically, homomorphic task requirements include homomorphic task type, homomorphic task quality, number of homomorphic encryption parties, homomorphic encryption party parameters, number of homomorphic users, and homomorphic user parameters.

[0378] In one possible implementation, the homomorphic task requirement may be sent in the form of a homomorphic task request message, and the parameters of the homomorphic task request message may be as shown in Table 2.

[0379] Table 2 Parameters of homomorphic task request message

[0380] It should be noted that the above-mentioned homomorphic task requirements are only examples and this application does not limit them.

[0381] S605: The first AMF sends a handover request message to the target base station.

[0382] Accordingly, the target base station receives the handover request information from the first AMF.

[0383] The switching request information includes homomorphic task requirements.

[0384] In one possible implementation, the first AMF selects a target base station that meets the homomorphic task requirements based on the homomorphic task requirements, and sends a switching request message to the target base station.

[0385] S606: The target base station sends a handover request confirmation message to the first AMF.

[0386] Accordingly, the first AMF receives a handover request confirmation message from the target base station.

[0387] In one possible implementation, after receiving the handover request information, the target base station determines whether it meets the homomorphic task requirements. If the homomorphic task requirements are met, it sends a handover request confirmation message to the first AMF, carrying the homomorphic capability information of the target base station. The homomorphic capability information of the target base station can refer to the relevant description of the homomorphic capability information in S509 above, which will not be repeated here.

[0388] Furthermore, when the terminal device switches to the first AMF, according to the root key of the first AMF (the first K AMF ) Re-determine the homomorphic encryption and decryption algorithm and re-derive the homomorphic key. Depending on the entity that determines the homomorphic encryption and decryption algorithm and derives the homomorphic key, there are the following situations:

[0389] Case 1: The first AMF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key.

[0390] Case 2: The HECF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key.

[0391] Case 3: HECF determines the homomorphic encryption and decryption algorithm and derives the homomorphic key.

[0392] The above three situations are further described in detail below with reference to FIG. 6 .

[0393] Case 1: The first AMF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key. That is, at this time, the first AMF acts as both the homomorphic encryptor and the key generator on the network side, and the terminal device acts as both the homomorphic decryptor and the key generator on the terminal side. Method 600 may also include S607-S622.

[0394] S607: The first AMF determines the homomorphic encryption and decryption algorithm and key derivation parameters.

[0395] A possible implementation method is that after the first AMF receives the confirmation information from the switching request, if the target AMF and the target base station are both homomorphic participants of the homomorphic task, if it is determined that the homomorphic capability of the target base station and the homomorphic capability of the first AMF meet the homomorphic task requirements, the first AMF determines the homomorphic encryption and decryption algorithm and key derivation parameters based on the homomorphic capability information of the target base station and the homomorphic capability information of the first AMF.

[0396] The key derivation parameter is the second key parameter in S420.

[0397] Optionally, if the first AMF determines that the homomorphic capabilities of the target base station and the first AMF do not meet the homomorphic task requirements, the first AMF reselects a target base station and target AMF that meet the homomorphic task requirements. S608: The first AMF derives a new homomorphic encryption and decryption key.

[0398] Specifically, the first AMF is based on the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0399] S609: The first AMF derives a new homomorphic computation key.

[0400] Specifically, the first AMF derives a new homomorphic computing key based on the homomorphic encryption and decryption key.

[0401] S610: The first AMF sends a create terminal device context response message to the second AMF.

[0402] Correspondingly, the second AMF receives the create terminal device context response information from the first AMF.

[0403] S611: The first AMF sends information about the homomorphic computation key and homomorphic task to the target base station.

[0404] Accordingly, the target base station receives the homomorphic computation key and homomorphic task information from the first AMF.

[0405] For the description of the above-mentioned homomorphic task information, please refer to the relevant description of the homomorphic task information in S517, which will not be repeated here.

[0406] S612: The second AMF sends a key change indication to the source base station. Correspondingly, the source base station receives the key change indication from the second AMF.

[0407] The key change indication is used to indicate that the root key of the first AMF is updated.

[0408] Exemplarily, the key change indication may include a flag. When flag=1, the key change indication is used to indicate that the root key of the first AMF is updated; when flag=0, the key change indication is used to indicate that the root key of the first AMF is not updated.

[0409] In one possible implementation, the first AMF sends a NAS security mode command to the terminal device, where the NAS security mode command includes a key change indication.

[0410] S613: The source base station sends a key change indication to the terminal device. Correspondingly, the terminal device receives the key change indication from the source base station. Specifically, the source base station forwards the key change indication received in S612 to the terminal device.

[0411] In a possible implementation, the source base station sends a switching command to the terminal device, where the switching command includes a key change indication.

[0412] S614, the terminal device performs cell switching.

[0413] Specifically, after receiving the handover command, the terminal device separates from the source cell, completes random access with the target base station, and accesses a new cell.

[0414] S615: The terminal device generates the first K AMF .

[0415] Specifically, after receiving the key change identifier, the terminal device learns that the root key of the network device to which the terminal device is connected has changed. Further, the terminal device generates the root key of the network device to which the terminal device is newly connected according to the preset protocol, that is, the first K AMF .

[0416] S616: The terminal device derives a new homomorphic key.

[0417] Specifically, the terminal device generates a signal according to the first K AMF , homomorphic encryption and decryption algorithms and key derivation parameters to derive new homomorphic encryption and decryption keys, and derive new homomorphic computing keys based on the homomorphic encryption and decryption keys.

[0418] S617, the terminal device sends a switching confirmation message to the target base station.

[0419] Correspondingly, the target base station receives the switching confirmation information from the terminal device.

[0420] Specifically, after the terminal device successfully randomly accesses the target base station, it sends a switching confirmation message to the target base station.

[0421] It should be noted that this application does not limit the order of S616 and S617. For example, S616 can be executed first and then S617; or S617 can be executed first and then S616; or S616 and S617 can be executed at the same time, etc.

[0422] Optionally, in S618, the terminal device sends uplink data to the target base station. Correspondingly, the target base station receives the uplink data from the terminal device.

[0423] Among them, the uplink data includes data related to homomorphic computing.

[0424] Exemplarily, data related to homomorphic computing can be homomorphic ciphertext after homomorphic encryption, for example, AI models of terminal devices, perception data and other private data.

[0425] Optionally, in S619, the target base station performs homomorphic computing.

[0426] Specifically, when the target base station needs to serve as a homomorphic computing party in a homomorphic task, the target base station performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0427] The specific process of homomorphic computing can refer to the relevant description of homomorphic computing technology in the prior art, and this application is not limited to this.

[0428] Optionally, in S620, the target base station sends handover notification information to the first AMF. Correspondingly, the first AMF receives the handover notification information from the target base station.

[0429] The handover notification information is used to notify the target base station that the handover is successful.

[0430] Exemplarily, the handover notification information may be HandOver Notify.

[0431] Optionally, in S621, the target base station sends downlink data to the terminal device. Correspondingly, the terminal device receives the downlink data from the target base station.

[0432] Among them, downlink data includes data related to homomorphic computing.

[0433] Exemplarily, data related to homomorphic computing can be homomorphic ciphertext after homomorphic encryption, such as AI models, perception data and other private data.

[0434] Optionally, in S622, the terminal device performs homomorphic computing.

[0435] Specifically, when a terminal device needs to act as a homomorphic computing party in a homomorphic task, the terminal device performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0436] Optionally, the second AMF sends a terminal device context release command to the source base station. Specifically, when the handover process is completed, the second AMF sends a terminal device context release command to the source base station.

[0437] The terminal device context release command is used to notify the source base station to release the context information of the terminal device.

[0438] Case 2: The HECF determines the homomorphic encryption and decryption algorithm, and the first AMF and the terminal device derive the homomorphic key. That is, at this time, the first AMF acts as both the homomorphic encryption party and the key generator on the network side, and the terminal device acts as both the homomorphic decryption party and the key generator on the terminal side. Method 600 may also include S623-S629.

[0439] S623, the first AMF sends the first information to the HECF. Correspondingly, the HECF receives the first information from the first AMF. The first information includes the homomorphic task requirements, the first K AMF , the homomorphic capability of the target base station, and the homomorphic capability of the first AMF.

[0440] Specifically, after the first AMF receives the switching request confirmation information from the target base station, if the target AMF and the target base station are homomorphic participants of the homomorphic task, if it is judged that the homomorphic capability of the target base station and the homomorphic capability of the first AMF meet the homomorphic task requirements, the first AMF sends the first information to HECF.

[0441] S624: The HECF sends first indication information, where the first indication information is used to indicate the identifier and key derivation parameters of the homomorphic encryption and decryption algorithm.

[0442] Specifically, the HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters based on the first information, and sends first indication information to the first AMF and the terminal device respectively.

[0443] Furthermore, the first AMF and the terminal device derive a homomorphic key based on the homomorphic encryption and decryption algorithm and the key derivation parameters.

[0444] S625: The first AMF derives a new homomorphic encryption and decryption key.

[0445] Specifically, the first AMF is based on the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0446] S626: The first AMF derives a new homomorphic computation key.

[0447] Specifically, the first AMF derives a new homomorphic computing key based on the homomorphic encryption and decryption key.

[0448] S627: The terminal device derives a new homomorphic encryption and decryption key.

[0449] Specifically, the terminal device generates a signal according to the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0450] S628, the terminal device derives a new homomorphic computing key.

[0451] Specifically, the terminal device derives a new homomorphic computing key based on the homomorphic encryption and decryption key.

[0452] It should be noted that this application does not limit the order of S625-S626 and S627-S628.

[0453] S629: The first AMF sends information about the homomorphic computation key and the homomorphic task to the target base station.

[0454] Accordingly, the target base station receives the homomorphic computation key and homomorphic task information from the first AMF.

[0455] It should be understood that at this time, the target base station acts as a homomorphic computing party, receiving the homomorphic computing key and homomorphic task information from the first AMF to perform homomorphic computing.

[0456] For the description of the above-mentioned homomorphic task information, please refer to the relevant description of the homomorphic task information in S517, which will not be repeated here.

[0457] In the second case, S610, S612-S614, S618-S622 in the first case can still be executed and will not be repeated here.

[0458] Case 3: The HECF determines the homomorphic encryption and decryption algorithm and derives the homomorphic key. In this case, the key generator is the HECF, which sends the generated homomorphic key to the homomorphic encryption, decryption, and computation parties, respectively. Method 600 may further include S630-S635.

[0459] S630: The first AMF sends first information to the HECF. Correspondingly, the HECF receives the first information from the first AMF.

[0460] The specific content of S630 can be found in S623 and will not be repeated here.

[0461] S631, HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters.

[0462] Specifically, the HECF determines the homomorphic encryption and decryption algorithm and key derivation parameters based on the homomorphic capability information of the target base station and the homomorphic capability information of the first AMF.

[0463] The key derivation parameter is the second key parameter in S420.

[0464] S632, HECF derives a new homomorphic encryption and decryption key.

[0465] Specifically, HECF is based on the first K AMF , homomorphic encryption and decryption algorithm and key derivation parameters to derive new homomorphic encryption and decryption keys.

[0466] S633, HECF derives a new homomorphic computing key.

[0467] Specifically, the HECF homomorphic encryption and decryption key derives a new homomorphic computing key.

[0468] S634, HECF sends the homomorphic computing key and homomorphic task information to the target base station.

[0469] Correspondingly, the target base station receives the homomorphic computation key and homomorphic task information from the HECF.

[0470] For the description of the above-mentioned homomorphic task information, please refer to the relevant description of the homomorphic task information in S517, which will not be repeated here.

[0471] S635, HECF sends the homomorphic key.

[0472] Specifically, HECF sends the homomorphic encryption key to the first AMF (homomorphic encryption party), sends the homomorphic decryption key to the terminal device (homomorphic decryption party), and sends the homomorphic computing key and homomorphic task information to the target base station (homomorphic computing party).

[0473] It should be noted that, in case three, S610, S612-S614, S618-S622 in case one can still be executed and will not be repeated here.

[0474] Based on the above scheme, in the mobility management process, when the superior key of the homomorphic key of the homomorphic task of the terminal device is updated due to base station switching, the homomorphic key can be re-derived in time according to the superior key of the updated homomorphic key, thereby ensuring the continuity of the homomorphic task of the terminal device during the switching process.

[0475] FIG7 is a schematic diagram of a communication method 700 based on homomorphic encryption provided by an embodiment of the present application. In a homomorphic task, if the homomorphic participants have not changed, and only the superior key of the homomorphic key is updated, if the homomorphic encryption and decryption key is generated based on the root key of the homomorphic encryption party (that is, the root key of the homomorphic encryption party is the superior key of the homomorphic encryption and decryption key), if the root key is updated, the homomorphic encryption and decryption key is updated, and therefore it is necessary to re-derive the homomorphic key based on the updated root key to ensure the continuity of the homomorphic task. Method 700 is described in detail below in conjunction with FIG7.

[0476] S710: The key generator derives a new homomorphic key.

[0477] Among them, homomorphic keys include homomorphic encryption keys, homomorphic decryption keys and homomorphic computation keys.

[0478] Among them, the key generating party can be a network device (for example, a base station), a terminal device, a network function, etc., and this application does not limit this.

[0479] Specifically, when the superior key of the homomorphic key is updated, the key generator re-derives the homomorphic key based on the updated superior key.

[0480] In one possible implementation, when the key generator is also a homomorphic encryption party, for example, when the key generator is gNB#1, gNB#1 uses its own updated root key K gNB1 Derive new homomorphic encryption keys, homomorphic decryption keys, and homomorphic computation keys.

[0481] In one possible implementation, when the key generator is a network function, for example, the key generator is AMF, AMF generates the key based on its own updated root key K AMF Derive new homomorphic encryption keys, homomorphic decryption keys, and homomorphic computation keys.

[0482] It should be understood that the key generator derives homomorphic encryption and decryption keys and homomorphic decryption keys based on the superior key, and the specific process of deriving homomorphic computing keys based on the homomorphic encryption and decryption keys can refer to the relevant process of deriving homomorphic keys by the key generator in the prior art, and this application does not limit this.

[0483] Optionally, in S720, the key generation party sends the homomorphic encryption key to the homomorphic encryption party.

[0484] Among them, the homomorphic encryption party can be a network device (for example, a base station), a terminal device, a network function, etc., and this application does not limit this.

[0485] In one possible implementation, when the key generator is also the homomorphic encryption party, the homomorphic encryption party obtains a re-derived homomorphic encryption key.

[0486] For example, when both the key generator and the homomorphic encryption party are gNB#1, gNB#1 obtains the re-derived homomorphic encryption key.

[0487] In one possible implementation, when the key generator is a network function, the key generator sends the re-derived homomorphic encryption key to the homomorphic encryptor.

[0488] For example, when the key generator is AMF and the homomorphic encryption party is gNB#1, AMF sends the re-derived homomorphic encryption key to gNB#1.

[0489] S730: The key generation party sends the homomorphic decryption key to the homomorphic decryption party.

[0490] Among them, the homomorphic decryption party can be a network device (for example, a base station), a terminal device, a network function, etc., and this application does not limit this.

[0491] Specifically, after the key generator re-derives the homomorphic decryption key, the new homomorphic decryption key is sent to the homomorphic decryption party.

[0492] In one possible implementation, when the key generator is gNB#1 and the homomorphic decryption provider is gNB#3, gNB#1 sends the re-derived homomorphic decryption key to gNB#3.

[0493] For example, gNB#1 sends the derived new homomorphic decryption key to gNB#3 via the Xn interface.

[0494] In one possible implementation, when the key generator is the AMF and the homomorphic decryption party is gNB#3, the AMF sends the re-derived homomorphic decryption key to gNB#3.

[0495] For example, the AMF sends the derived new homomorphic decryption key to gNB#3 via the Ng interface.

[0496] S740: The key generation party sends the homomorphic computing key to the homomorphic computing party.

[0497] Among them, the homomorphic computing party can be a network device (for example, a base station), a terminal device, a network function, etc., and this application does not limit this.

[0498] Specifically, after the key generator re-derives the homomorphic computing key, the new homomorphic computing key is sent to the homomorphic computing party.

[0499] For example, when the key generator is gNB#1 and the homomorphic computation party is gNB#2, gNB#1 sends the re-derived homomorphic computation key to gNB#2.

[0500] For example, when the key generator is AMF and the homomorphic computation party is gNB#2, AMF sends the re-derived homomorphic computation key to gNB#2.

[0501] Optionally, the key generation party sends information about the homomorphic task to the homomorphic computing party.

[0502] For the description of the above-mentioned homomorphic task information, please refer to the relevant description of the homomorphic task information in S517, which will not be repeated here.

[0503] It should be understood that in method 700, gNB#1, gNB#2, and gNB#3 can be network devices accessed by terminal devices, and this application does not limit this.

[0504] Based on the above scheme, in the communication system, when the homomorphic participants of the homomorphic task in which the terminal device participates have not changed, but the superior key of the homomorphic key has changed, the homomorphic participants can re-derive the homomorphic key based on the superior key of the updated homomorphic key, thereby ensuring the continuity of the homomorphic task of the terminal device.

[0505] Figure 8 is a schematic diagram of a communication method 800 based on homomorphic encryption provided by an embodiment of the present application. In a homomorphic task, if the homomorphic participants change, such as when the connected terminal device switches from the source base station (corresponding to the source cell) to the target base station (corresponding to the target cell), the RSRP of the source base station becomes weaker and weaker, and the RSRP of the target base station becomes stronger and stronger. At this time, the homomorphic computing party switches from the source base station to the target base station (that is, the homomorphic computing party changes), but if the superior key of the homomorphic encryption and decryption key has not changed, there is no need to re-derive the homomorphic key. The new homomorphic computing party needs to obtain the homomorphic computing key related to the homomorphic task to ensure the continuity of the homomorphic task. In Figure 8, the source base station is the old homomorphic computing party, and the target base station is the new homomorphic computing party. The method 800 is described in detail below in conjunction with Figure 8.

[0506] S801: The source base station sends a handover request message to the target base station.

[0507] Specifically, the terminal device performs downlink measurement (for example, downlink measurement based on SSB or downlink measurement based on CSI-RS) and reports the measurement report to the source base station. The source base station makes a handover decision (HO decision) based on the measurement report reported by the terminal device and the wireless resource management information on the source base station, selects a target base station for the terminal device, and sends a handover request information (for example, HO Request message) to the target base station.

[0508] The handover request information includes at least one of the following: terminal device security capability, encryption / security policy, next hop chaining counter parameter (NCC), K NG-RAN* , homomorphic task requirements.

[0509] Among them, the terminal device security capabilities are used to indicate the encryption algorithms and integrity protection algorithms supported by the terminal device, as well as the homomorphic encryption algorithms supported by the terminal device.

[0510] Homomorphic task requirements include at least one of the following: homomorphic task type, homomorphic task quality, number of homomorphic encryption parties, homomorphic encryption party parameters, number of homomorphic users, and homomorphic user parameters. For the above homomorphic task requirements, please refer to the relevant description of homomorphic task requirements in S604 and will not be repeated here.

[0511] S802: The target base station performs handover admission control.

[0512] Specifically, after receiving the handover request information, the target base station determines whether the homomorphic capability of the target base station can meet the homomorphic task requirement.

[0513] It should be understood that if the target base station allows the terminal device to be handed over to the target cell, dedicated admission resources will be allocated to the terminal device.

[0514] S803: The target base station reports the homomorphic capability information of the target base station.

[0515] In one possible implementation, the target base station reports its own homomorphic capability information to the core network element.

[0516] In a possible implementation, the target base station reports to the HECF the homomorphic task requirements of the terminal device in the cell handover and the homomorphic capability information of the target base station.

[0517] For the homomorphic capability information of the target base station, reference may be made to the related description of the homomorphic capability information in S509 , which will not be repeated here.

[0518] It should be understood that the target base station reports its own homomorphic capability information to the key generator (core network element or HECF), so that the key generator can determine the homomorphic algorithm used to generate the homomorphic key based on the homomorphic capability information of the target base station, thereby ensuring the smooth execution of the homomorphic task.

[0519] S804: The target base station sends a handover request response message to the source base station.

[0520] Correspondingly, the source base station receives the handover request response information from the target base station.

[0521] In one possible implementation, if the target base station determines in S802 that its homomorphic capability meets the homomorphic task requirements, the handover request response sent by the target base station to the source base station is a handover request confirmation message (HO Req terminal device st ACK message), and the handover request response includes the information required for the terminal device to access the target cell.

[0522] One possible implementation method is that if the target base station determines in S802 that its own homomorphic capability does not meet the homomorphic task requirements, the switching request response sent by the target base station to the source base station includes switching preparation failure information, and the switching preparation failure information includes a reason value, for example, the target base station does not meet the homomorphic task requirements.

[0523] S805: The source base station sends a handover command to the terminal device.

[0524] Accordingly, the terminal device receives a switching command from the source base station.

[0525] In a possible implementation, the handover command is carried in an RRC message. Optionally, the handover command is an HO Command message, which carries parameter information required for the terminal device to hand over to the target cell.

[0526] S806, the terminal device switches from the source cell to the target cell.

[0527] Specifically, after receiving the handover command, the terminal device performs HO handover, the terminal device interrupts the wireless connection with the source base station, and then synchronizes to the target base station.

[0528] S807, the source base station sends the status information of the terminal device to the target base station.

[0529] Correspondingly, the target base station receives the status information of the terminal device from the source base station.

[0530] Exemplarily, the status information of the terminal device is a serial number status transfer process.

[0531] S808: The target base station obtains information about the homomorphic computing key and the homomorphic task.

[0532] In one possible implementation, the source base station sends information about the homomorphic computing key and the homomorphic task to the target base station.

[0533] It should be understood that there is an Xn link between the source cell and the target cell to which the terminal device switches, and the source base station exchanges homomorphic task requirements, homomorphic calculation keys, and homomorphic task information with the target base station through the Xn port.

[0534] It should be understood that at this time, the source base station, as the old homomorphic computing party, sends the homomorphic computing key related to the homomorphic task to the new homomorphic computing party, that is, the target base station.

[0535] In one possible implementation, the HECF sends information about the homomorphic computing key and the homomorphic task to the target base station.

[0536] It should be understood that if in S803, the target base station reports to HECF the homomorphic task requirements in which the terminal device in the cell switching participates, as well as the homomorphic capability information of the target station, HECF can send the homomorphic calculation key and homomorphic task information of the homomorphic task in which the terminal device participates to the target base station.

[0537] S809, the terminal device sends a switching confirmation message to the target base station.

[0538] Correspondingly, the target base station receives the switching confirmation information from the terminal device.

[0539] Specifically, in S806, after the terminal device completes random access with the target base station, it sends handover confirmation information to the target base station.

[0540] S810: The target base station sends a path switching request message to the core network.

[0541] Correspondingly, the core network receives a path switching request from the target base station.

[0542] The path switching request information includes the terminal device security capability.

[0543] It should be understood that after receiving the path switching request from the target base station, the core network increases the next hop chaining counter (NCC) by 1 (ie, NCC+1) and updates the next hop parameter (NH) (ie, new NH).

[0544] Optionally, in S811, the target base station sends downlink data to the terminal device, and the terminal device receives the downlink data.

[0545] Among them, downlink data includes data related to homomorphic computing.

[0546] Exemplarily, data related to homomorphic computing can be homomorphic ciphertext after homomorphic encryption, such as AI models, perception data, etc.

[0547] Optionally, in S812, the terminal device performs homomorphic computing.

[0548] Specifically, when a terminal device needs to act as a homomorphic computing party in a homomorphic task, the terminal device performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0549] For the specific process of homomorphic computing, reference can be made to the relevant processes of homomorphic computing in the prior art, and this application does not limit this.

[0550] S813: The core network sends a path switching request confirmation message to the target base station.

[0551] In a possible implementation manner, the path switch request confirmation information includes the NCC+1 and the new NH updated in S810.

[0552] Optionally, S814, the terminal device sends uplink data to the target base station.

[0553] Correspondingly, the target base station receives uplink data from the terminal device.

[0554] Among them, the uplink data includes data related to homomorphic computing.

[0555] Among them, the uplink data includes data related to homomorphic computing.

[0556] Exemplarily, data related to homomorphic computing can be homomorphic ciphertext after homomorphic encryption, such as AI models, perception data, etc.

[0557] Optionally, in S815, the target base station performs homomorphic computing.

[0558] Specifically, when the target base station needs to serve as a homomorphic computing party in a homomorphic task, the target base station performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0559] Based on the above scheme, when the terminal device switches from the source base station to the target base station, the target base station, as the new homomorphic computing party, can obtain the homomorphic computing key, homomorphic task requirements and other related information of the homomorphic task corresponding to the terminal device from the source base station or HECF to complete the homomorphic task, thereby ensuring the continuity of the homomorphic task of the terminal device during the switching process.

[0560] Figure 9 is a schematic diagram of a communication method 900 based on homomorphic encryption provided by an embodiment of the present application. In a homomorphic task, if the homomorphic participants change, such as the RRC inactive state between the terminal device and the access node (for example, RAN), and the CM-CONNECTED state between the access node and the core network, when the air interface connection between the terminal device and the access node is released, but the connection between the AMF and the access node, and the connection between the access node and the UPF exist, if the terminal device receives a paging based on the access node or the terminal device has data to be sent to the network side, the terminal device triggers the RRC_Inactive state to switch to RRC_Connected. At this time, the homomorphic computing party is switched from the base station (source base station) of the previous service terminal device to the target base station (that is, the homomorphic computing party has changed), but if the superior key of the homomorphic key has not changed, there is no need to re-derive the homomorphic key. The new homomorphic computing party needs to obtain the homomorphic computing key related to the homomorphic task to ensure the continuity of the homomorphic task. In Figure 9, the source base station is the old homomorphic computing party, and the target base station is the new homomorphic computing party. The method 900 is described in detail below with reference to FIG. 9 .

[0561] S901: The terminal device sends an RRC wake-up request message to the target base station. Correspondingly, the target base station receives the RRC wake-up request message from the terminal device.

[0562] Among them, the RRC wake-up request information is used to request that the terminal device be switched from the RRC_Inactive state to the RRC_Connected state.

[0563] In one possible implementation, the terminal device and the access node are in the RRC inactive state, the air interface connection between the terminal device and the access node is released, the access node and the core network are in the CM-CONNECTED state, and there are connections between the AMF and the access node, and between the access node and the UPF. If the terminal device receives a paging based on the access node or the terminal device has data to send to the network side, the terminal device sends an RRC wake-up request message to the target base station.

[0564] S902: The target base station sends a request message for obtaining a terminal device context to the source base station. Correspondingly, the source base station receives the request message for obtaining a terminal device context from the target base station.

[0565] S903: The source base station sends a terminal device context acquisition response message to the target base station. Correspondingly, the target base station receives the terminal device context acquisition response message from the source base station.

[0566] A possible implementation method is to obtain the terminal device context response information including homomorphic task requirements, homomorphic computing keys and homomorphic task information.

[0567] In a possible implementation, obtaining the terminal device context response information includes homomorphic task requirements.

[0568] The above homomorphic task requirements can refer to the relevant description in S604, and the information of the homomorphic task can refer to the relevant description in S517, which will not be repeated here.

[0569] S904: The target base station determines whether the homomorphic capability of the served cell meets the homomorphic task requirement.

[0570] Specifically, after receiving the terminal device context acquisition response information, the target base station determines whether the homomorphic capability of the cell served by the target base station meets the homomorphic task requirements.

[0571] In one possible implementation, when the target base station determines that the homomorphic capability of the served cell meets the homomorphic task requirement, the target base station reports its own homomorphic capability information.

[0572] One possible implementation method is that when the target base station determines that the homomorphic capability of the cell it serves does not meet the homomorphic task requirements, the target base station sends an indication message to the source base station or the core network to indicate that the homomorphic capability of the cell currently served by the target base station does not meet the homomorphic task requirements. Further, the source base station or the core network re-determines the target base station to perform the homomorphic task.

[0573] S905: The target base station reports the homomorphic capability information of the target base station.

[0574] Specifically, when the target base station determines that the homomorphic capability of the served cell meets the homomorphic task requirement, it reports its own homomorphic capability information.

[0575] In one possible implementation, the target base station reports its own homomorphic capability information to the core network.

[0576] In a possible implementation, the target base station reports to the HECF the homomorphic task requirements of the terminal device in the cell handover and the homomorphic capability information of the target base station.

[0577] For the homomorphic capability information of the target base station, reference may be made to the related description of the homomorphic capability information in S509 , which will not be repeated here.

[0578] S906: The target base station sends RRC wake-up information to the terminal device. Correspondingly, the terminal device receives the RRC wake-up information from the target base station.

[0579] S907: The terminal device sends an RRC wake-up completion message to the target base station. Correspondingly, the target base station receives the RRC wake-up completion message from the terminal device.

[0580] Specifically, after the terminal device switches from the RRC inactive state to the RRC_Connected state according to the RRC wake-up information, it sends an RRC wake-up completion message to the target base station.

[0581] Optionally, in S908, the HECF sends information about the homomorphic computing key and the homomorphic task to the target base station.

[0582] It should be understood that if in S903, the source base station sends to the target base station a response message for obtaining the terminal device context including only homomorphic task requirements, and in S905, the target base station reports to HECF the homomorphic task requirements in which the terminal device in the cell switching participates, as well as the homomorphic capability information of the target station, HECF can send the homomorphic calculation key of the homomorphic task in which the terminal device participates and the information of the homomorphic task to the target base station.

[0583] S909: The target base station sends a path switching request message to the core network. Correspondingly, the core network receives the path switching request message from the target base station.

[0584] The path switching request information is used to request that the base station to which the terminal device accesses be switched from the source base station to the target base station.

[0585] S910: The core network sends a path switching request response message to the target base station. Correspondingly, the target base station receives the path switching request response message from the core network.

[0586] The path switching request response information is used to indicate that the base station to which the terminal device is accessed is allowed to be switched from the source base station to the target base station.

[0587] S911: The target base station sends terminal device context release information to the source base station. Correspondingly, the source base station receives the terminal device context release information from the target base station.

[0588] The terminal device context release information is used to instruct the source base station to release the context information of the terminal device.

[0589] Optionally, in S912, the core network sends downlink data to the target base station.

[0590] Among them, downlink data includes data related to homomorphic computing.

[0591] Exemplarily, data related to homomorphic computing can be homomorphic ciphertext after homomorphic encryption, such as AI models, perception data and other private data.

[0592] Optionally, in S913, the target base station performs homomorphic computing.

[0593] Specifically, when the target base station needs to serve as a homomorphic computing party in a homomorphic task, the target base station performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0594] Optionally, S914, the target base station sends downlink data to the terminal device.

[0595] Optionally, in S915, the terminal device performs homomorphic computing.

[0596] Specifically, when a terminal device needs to act as a homomorphic computing party in a homomorphic task, the terminal device performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0597] Optionally, S916, the terminal device sends uplink data to the target base station.

[0598] Among them, the uplink data includes data related to homomorphic computing.

[0599] Exemplarily, data related to homomorphic computing can be homomorphic ciphertext after homomorphic encryption, such as AI models, perception data and other private data.

[0600] Optionally, in S917, the target base station performs homomorphic computing.

[0601] Specifically, when the target base station needs to serve as a homomorphic computing party in a homomorphic task, the target base station performs homomorphic computing on data related to the homomorphic computing according to the homomorphic task requirements and the homomorphic computing key.

[0602] Based on the above scheme, when the terminal device switches from the source base station to the target base station, the target base station, as the new homomorphic computing party, can obtain relevant information of the homomorphic task corresponding to the terminal device, such as the homomorphic computing key, homomorphic task requirements, etc. from the source base station or HECF to complete the homomorphic task, thereby ensuring the continuity of the homomorphic task of the terminal device during the switching process.

[0603] Figure 10 is a schematic diagram of a communication method 1000 based on homomorphic encryption provided by an embodiment of the present application. In a homomorphic task, if the homomorphic participants change, the homomorphic computing party switches from homomorphic computing party #1 to homomorphic computing party #2 (for example, the source base station switches to the target base station, or the old AMF switches to the new AMF, or the old UPF switches to the new UPF (for example, the UPF switching caused by the UE moving out of a certain range), etc.), but the superior key of the homomorphic encryption and decryption key does not change (for example, the APP service homomorphic encryption and decryption key K APP , the homomorphic encryption and decryption key K of the core network element enc), there is no need to re-derive the homomorphic key. The new homomorphic computing party needs to obtain the homomorphic computing key related to the homomorphic task to ensure the continuity of the homomorphic task. The method 1000 is described in detail below with reference to FIG10.

[0604] S1001, homomorphic computing party #2 obtains homomorphic computing key and homomorphic task information.

[0605] In one possible implementation, homomorphic computing party #2 receives homomorphic computing keys and homomorphic task information from homomorphic computing party #1.

[0606] Among them, homomorphic computing party #1 is the homomorphic computing party before switching, and homomorphic computing party #2 is the homomorphic computing party after switching.

[0607] Among them, the homomorphic computing party can be a network device (for example, a base station), a terminal device, a network function, etc., and this application does not limit this.

[0608] Exemplarily, the first UPF receives the homomorphic computing key and homomorphic task information from the second UPF. Specifically, the second UPF sends the homomorphic computing key and homomorphic task information to the first UPF through the Xn port.

[0609] In one possible implementation, homomorphic computing party #2 receives homomorphic computing keys and homomorphic task information from HECF.

[0610] Exemplarily, the first UPF receives the homomorphic computing key and homomorphic task information from the HECF. Specifically, the HECF sends the homomorphic computing key and homomorphic task information to the first UPF through the Ng port.

[0611] For information about the above homomorphic tasks, please refer to the relevant description in S516 and will not be repeated here.

[0612] Optionally, when the homomorphic computing party #2 receives the homomorphic computing key and the homomorphic task information from the HECF, before S1001, the method S1000 further includes:

[0613] S1002, homomorphic computing party #1 sends homomorphic task requirements to homomorphic computing party #2.

[0614] Correspondingly, homomorphic computing party #2 receives the homomorphic task request from homomorphic computing party #1.

[0615] Optionally, the homomorphic task requirement includes an identifier of the homomorphic task, and the identifier of the homomorphic task is used to determine the homomorphic key corresponding to the homomorphic task and the information of the homomorphic task according to the identifier.

[0616] The above homomorphic task requirements can be referred to the relevant description in S604 and will not be repeated here.

[0617] S1003, homomorphic computing party #2 sends homomorphic task requirements and homomorphic capability information of homomorphic computing party #2 to HECF.

[0618] Accordingly, HECF receives the homomorphic task requirements and homomorphic capability information of homomorphic computing party #2 from homomorphic computing party #2.

[0619] The homomorphic capability information of the above-mentioned homomorphic computing party #2 can be referred to the relevant description in S509 and will not be repeated here.

[0620] S1004, HECF determines the homomorphic computing key and homomorphic task information.

[0621] Specifically, HECF determines the homomorphic computing key and homomorphic task information based on the homomorphic task requirements and the homomorphic capability information of the homomorphic computing party #2.

[0622] In one possible implementation, when the homomorphic task requirement includes an identifier of the homomorphic task, the HECF determines the homomorphic key and homomorphic task information corresponding to the homomorphic task based on the identifier of the homomorphic task.

[0623] Based on the above scheme, when the homomorphic computing party of the homomorphic task corresponding to the terminal device changes due to the movement of the terminal device, the new homomorphic computing party can obtain relevant information of the homomorphic task such as the homomorphic computing key and homomorphic task requirements to complete the homomorphic task, thereby ensuring the continuity of the homomorphic task of the UE during the movement.

[0624] It should be understood that the examples in Figures 4 to 10 of the embodiments of the present application are merely intended to facilitate understanding of the embodiments of the present application by those skilled in the art, and are not intended to limit the embodiments of the present application to the specific scenarios illustrated. Those skilled in the art can obviously make various equivalent modifications or variations based on the examples in Figures 4 to 10, and such modifications or variations also fall within the scope of the embodiments of the present application.

[0625] It can also be understood that some optional features in the various embodiments of the present application may not depend on other features in certain scenarios, and may also be combined with other features in certain scenarios, without limitation.

[0626] It can also be understood that the solutions in the various embodiments of the present application can be reasonably combined and used, and the explanations or descriptions of the various terms appearing in the embodiments can be referenced or explained with each other in the various embodiments, without limitation to this.

[0627] It can also be understood that the sizes of the various numerical serial numbers in the embodiments of the present application do not mean the order of execution, but are only distinguished for the convenience of description and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0628] It can also be understood that in the various embodiments of the present application, some message names are involved, such as homomorphic capability information or first key parameters, etc. It should be understood that their naming does not limit the scope of protection of the embodiments of the present application.

[0629] It can also be understood that in the above-mentioned various method embodiments, the methods and operations implemented by the key generator (first network device, HECF, terminal device) can also be implemented by components (such as chips or circuits) or functional modules that can be used by the key generator without limitation. Corresponding to the methods given in the above-mentioned various method embodiments, the embodiments of the present application also provide corresponding devices, which include modules for executing the corresponding embodiments of the above-mentioned various methods. The module can be software, hardware, or a combination of software and hardware. It can be understood that the technical features described in the above-mentioned various method embodiments are also applicable to the following device embodiments.

[0630] It should be understood that the key generator (first network device, HECF, terminal device) can perform some or all of the steps in the above embodiments. These steps or operations are only examples. The embodiments of the present application can also perform other operations or variations of various operations. In addition, the various steps can be performed in a different order than those presented in the above embodiments, and it is possible that not all operations in the above embodiments need to be performed.

[0631] The communication method provided in the embodiment of the present application is described in detail above in conjunction with Figures 4 to 10. The communication device provided in the embodiment of the present application is described in detail below in conjunction with Figures 11 to 13. It should be understood that the description of the device embodiment corresponds to the description of the method embodiment. Therefore, for matters not described in detail, please refer to the method embodiment above. For the sake of brevity, some contents will not be repeated.

[0632] Figure 11 is a schematic block diagram of a communication device provided in an embodiment of the present application. The device 1100 includes a transceiver unit 1110, which can be used to implement corresponding communication functions. The transceiver unit 1110 can also be called a communication interface or a communication unit.

[0633] Optionally, the device 1100 may further include a processing unit 1120 , which may be configured to perform data processing.

[0634] Optionally, the device 1100 also includes a storage unit, which can be used to store instructions and / or data, and the processing unit 1120 can read the instructions and / or data in the storage unit so that the device implements the actions of different devices in the aforementioned method embodiments, for example, the actions of the key generator (first network device, HECF, terminal device).

[0635] The device 1100 can be used to execute the actions performed by the key generator (first network device, HECF, terminal device) in the above method embodiments. In this case, the device 1100 can be the key generator (first network device, HECF, terminal device), or a component of the key generator (first network device, HECF, terminal device). The transceiver unit 1110 is used to execute the transceiver-related operations of the key generator (first network device, HECF, terminal device) in the above method embodiments, and the processing unit 1120 is used to execute the processing-related operations of the key generator (first network device, HECF, terminal device) in the above method embodiments.

[0636] It should also be understood that the apparatus 1100 herein is embodied in the form of a functional unit. The term "unit" herein may refer to an application specific integrated circuit (ASIC), an electronic circuit, a processor (e.g., a shared processor, a dedicated processor, or a group processor, etc.) and a memory for executing one or more software or firmware programs, a combined logic circuit, and / or other suitable components that support the described functions. In an optional example, those skilled in the art will appreciate that the apparatus 1100 may be specifically the key generator (first network device, HECF, terminal device) in the above-mentioned embodiment, and may be used to execute the various processes and / or steps corresponding to the key generator (first network device, HECF, terminal device) in the above-mentioned method embodiments. Alternatively, the apparatus 1100 may be specifically the key generator (first network device, HECF, terminal device) in the above-mentioned embodiment, and may be used to execute the various processes and / or steps corresponding to the key generator (first network device, HECF, terminal device) in the above-mentioned method embodiments. To avoid repetition, these will not be described in detail here.

[0637] The apparatus 1100 of each of the above-mentioned solutions has the function of implementing the corresponding steps performed by the key generator (first network device, HECF, terminal device) in the above-mentioned method, or the apparatus 1100 of each of the above-mentioned solutions has the function of implementing the corresponding steps performed by the key generator (first network device, HECF, terminal device) in the above-mentioned method. The functions can be implemented by hardware, or the corresponding software can be implemented by hardware. The hardware or software includes one or more modules corresponding to the above-mentioned functions; for example, the transceiver unit can be replaced by a transceiver (for example, the sending unit in the transceiver unit can be replaced by a transmitter, and the receiving unit in the transceiver unit can be replaced by a receiver), and other units, such as the processing unit, can be replaced by a processor to respectively perform the sending and receiving operations and related processing operations in each method embodiment.

[0638] In addition, the transceiver unit 1110 may also be a transceiver circuit (for example, may include a receiving circuit and a sending circuit), and the processing unit may be a processing circuit.

[0639] It should be noted that the apparatus in FIG11 may be a network element or device in the aforementioned embodiment, or may be a chip or chip system, such as a system on chip (SoC). The transceiver unit may be an input / output circuit or a communication interface; the processing unit may be a processor, microprocessor, or integrated circuit integrated on the chip. This is not limited here.

[0640] As shown in Figure 12, an embodiment of the present application provides another communication device 1200. The device 1200 includes a processor 1210, which is coupled to a memory 1220. The memory 1220 is used to store computer programs or instructions and / or data. The processor 1210 is used to execute the computer programs or instructions stored in the memory 1220, or read the data stored in the memory 1220, to perform the methods in the above method embodiments.

[0641] Optionally, there are one or more processors 1210. Optionally, there are one or more memories 1220. Optionally, the memories 1220 are integrated with the processor 1210 or are separately provided.

[0642] Optionally, as shown in Figure 12, the apparatus 1200 further includes a transceiver 1230, which is configured to receive and / or transmit signals. For example, the processor 1210 is configured to control the transceiver 1230 to receive and / or transmit signals.

[0643] As a solution, the device 1200 is used to implement the operations performed by the key generator (first network device, HECF, terminal device) in the above various method embodiments.

[0644] For example, the processor 1210 is configured to execute a computer program or instruction stored in the memory 1220 to implement the relevant operations of the key generator in each of the above method embodiments. For example, the key generator (first network device, HECF, terminal device) in any one of the embodiments shown in Figures 4 to 10, or the method of the key generator (first network device, HECF, terminal device) in any one of the embodiments shown in Figures 4 to 10.

[0645] It should be understood that the processor mentioned in the embodiments of the present application may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0646] It should also be understood that the memory mentioned in the embodiments of the present application may be a volatile memory and / or a non-volatile memory. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM). For example, RAM can be used as an external cache. By way of example and not limitation, RAM includes the following forms: static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct RAM bus RAM (DR RAM). The memory described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0647] It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, the memory (storage module) can be integrated into the processor.

[0648] As shown in FIG13 , an embodiment of the present application provides a chip system 1300 . The chip system 1300 (or also referred to as a processing system) includes a logic circuit 1310 and an input / output interface 1320 .

[0649] Logic circuit 1310 may be a processing circuit within chip system 1300. Logic circuit 1310 may be coupled to a storage unit and invoke instructions within the storage unit, enabling chip system 1300 to implement the methods and functions of various embodiments of the present application. Input / output interface 1320 may be an input / output circuit within chip system 1300, outputting information processed by chip system 1300 or inputting data or signaling information to be processed into chip system 1300 for processing.

[0650] As a solution, the chip system 1300 is used to implement the operations performed by the key generator (first network device, HECF, terminal device) in the above various method embodiments.

[0651] For example, the logic circuit 1310 is used to implement the processing-related operations by the key generator (first network device, HECF, terminal device) in the above method embodiments, such as the processing-related operations of the key generator in any one of the embodiments shown in Figures 4 to 10; the input / output interface 1320 is used to implement the sending and / or receiving-related operations by the key generator in the above method embodiments, such as the sending and / or receiving-related operations performed by the key generator in any one of the embodiments shown in Figures 4 to 10.

[0652] An embodiment of the present application also provides a computer-readable storage medium on which computer instructions are stored for implementing the methods executed by the key generator (first network device, HECF, terminal device) in the above-mentioned method embodiments.

[0653] For example, when the computer program is executed by a computer, the computer can implement the method performed by the key generator (first network device, HECF, terminal device) in each embodiment of the above method.

[0654] An embodiment of the present application also provides a computer program product, comprising instructions, which, when executed by a computer, implement the methods performed by the key generator (first network device, HECF, terminal device) in the above-mentioned method embodiments.

[0655] The explanation of the relevant contents and beneficial effects of any of the above-mentioned devices can be referred to the corresponding method embodiments provided above, which will not be repeated here.

[0656] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0657] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. For example, the computer can be a personal computer, a server, or a network device, etc. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk (SSD)). For example, the aforementioned available medium includes, but is not limited to, various media that can store program code, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0658] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0659] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0660] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0661] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment. In addition, the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0662] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0663] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method based on homomorphic encryption, characterized in that: include: The key generator obtains a first key parameter, where the first key parameter corresponds to a key parameter of an updated root key of a network device to which the terminal device is connected; The key generator derives a homomorphic encryption and decryption key based on the first key parameter and a homomorphic encryption and decryption algorithm, and the homomorphic encryption and decryption key is used for the homomorphic task in which the terminal device participates.

2. The method according to claim 1, characterized in that When the key generator is a first network device, the key generator obtains a first key parameter, including: The first network device receives a first key parameter from a second network device, the second network device is a network device connected to the terminal device before the switching, and the first network device is a network device connected to the terminal device after the switching; or The first network device generates the first key parameter, and the first network device is a network device to which the terminal device accesses.

3. The method according to claim 2, characterized in that The method further comprises: The first network device receives homomorphic capability information of the terminal device; The first network device determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the terminal device.

4. The method according to claim 3, characterized in that The first network device determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the terminal device, including: The first network device receives homomorphic capability information of a third network device; The first network device determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device, and the third network device is a device participating in executing the homomorphic task.

5. The method according to claim 3 or 4, characterized in that: The method further comprises: The first network device sends first indication information to the terminal device, where the first indication information is used to indicate an identifier of the homomorphic encryption and decryption algorithm.

6. The method according to claim 2, characterized in that The method further comprises: The first network device receives an identifier of the homomorphic encryption and decryption algorithm from a homomorphic management device HECF.

7. The method according to claim 1, characterized in that When the key generator is a homomorphic management device HECF, the key generator obtains the first key parameter, including: The HECF generates the first key parameter.

8. The method according to claim 7, characterized in that The method further comprises: The HECF receives homomorphic capability information of the terminal device; The HECF determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the terminal device.

9. The method according to claim 8, characterized in that The HECF determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the terminal device, including: The HECF receives homomorphic capability information of a third network device; The HECF determines the homomorphic encryption and decryption algorithm according to the homomorphic capability information of the third network device and the homomorphic capability information of the terminal device, and the third network device is a device participating in executing the homomorphic task.

10. The method according to any one of claims 7 to 9, characterized in that The method further comprises: The HECF sends the homomorphic encryption and decryption key to a first network device and the terminal device, where the first network device is a network device to which the terminal device accesses.

11. The method according to claim 1, characterized in that: When the key generator is a terminal device, the key generator obtains the first key parameter, including: The terminal device receives second indication information from a first network device, where the second indication information is used to indicate that a root key of a network device to which the terminal device is connected is updated, and the first network device is a network device to which the terminal device is connected; The terminal device generates the first key parameter according to the second indication information.

12. The method according to claim 11, characterized in that The method further comprises: The terminal device receives first indication information from the first network device or HECF, and the first indication information is used to indicate The identifier of the homomorphic encryption and decryption algorithm.

13. The method according to any one of claims 1 to 12, characterized in that The key generator derives a homomorphic encryption and decryption key according to the first key parameter and the homomorphic encryption and decryption algorithm, including: The key generator derives the homomorphic encryption and decryption key based on the first key parameter, the homomorphic encryption and decryption algorithm and the second key parameter, wherein the second key parameter includes at least one of the following: an identifier of the homomorphic encryption and decryption algorithm, a ciphertext modulus, a plaintext modulus, and a polynomial dimension.

14. The method according to any one of claims 1 to 13, characterized in that The method further comprises: The key generator obtains homomorphic task requirements, where the homomorphic task requirements are used to indicate parameters required to execute the homomorphic task; The key generator derives a homomorphic encryption and decryption key according to the first key parameter and the homomorphic encryption and decryption algorithm, including: When the key generator determines that the third network device meets the homomorphic task requirements, the key generator derives the homomorphic encryption and decryption key according to the first key parameters, the homomorphic encryption and decryption algorithm, and the homomorphic task requirements, and the third network device is a device participating in executing the homomorphic task.

15. A communication method based on homomorphic encryption, characterized in that: include: The second network device receives the homomorphic key and the information of the homomorphic task of the terminal device from the first network device or the homomorphic management device HECF, wherein the homomorphic key is used to execute the homomorphic task in which the terminal device participates; The second network device executes the homomorphic task according to the homomorphic key and information of the homomorphic task; The first network device is a network device that the terminal device accesses before switching, and the second network device is a network device that the terminal device accesses after switching.

16. The method according to claim 15, characterized in that Before the second network device receives the homomorphic key from the homomorphic management device HECF and the information of the homomorphic task of the terminal device, the method further includes: The second network device receives a homomorphic task requirement from the first network device, where the homomorphic task requirement is used to indicate parameters required to execute the homomorphic task; The second network device sends the homomorphic task requirement and the homomorphic capability information of the second network device to the homomorphic management device HECF, wherein the homomorphic computing key is determined according to the homomorphic task requirement and the homomorphic capability information of the second network device.

17. The method according to claim 15 or 16, characterized in that The second network device is a target base station, the first network device is a source base station, and the homomorphic computing key and the information of the homomorphic task are sent through the Xn interface.

18. The method according to claim 17, characterized in that Before the second network device receives the homomorphic key and the information of the homomorphic task from the first network device or the homomorphic management device HECF, the method further includes: The second network device receives the switching request information from the first network device, where the switching request information is used to instruct the network device to which the terminal device is connected to switch; The second network device sends a switching response message to the first network device, where the switching response message is used to indicate that the network device to which the terminal device is connected can be switched to the second network device.

19. The method according to claim 18, characterized in that The switching request information includes a homomorphic task requirement, and the second network device sends a switching response information to the first network device, including: When the second network device determines that the homomorphic task requirement is met, the second network device sends switching response information to the first network device.

20. The method according to claim 17, characterized in that Before the second network device receives the homomorphic key and the information of the homomorphic task from the first network device or the homomorphic management device HECF, the method further includes: The second network device receives a radio resource control (RRC) wake-up request message from the terminal device, where the RRC wake-up request message is used to request that the terminal device be switched from a non-connected state to a connected state; The second network device sends a request message for obtaining a context of a terminal device to the first network device; The second network device receives the homomorphic key and the information of the homomorphic task from the first network device or the homomorphic management device HECF, including: The second network device receives terminal device context acquisition response information from the first network device, where the terminal device context acquisition response information includes the homomorphic key and information about the homomorphic task.

21. The method according to claim 20, characterized in that After the second network device receives the homomorphic key and the information of the homomorphic task from the first network device or the homomorphic management device HECF, the method further includes: The second network device sends RRC wake-up information to the terminal device, where the RRC wake-up information is used to instruct the terminal device to switch from a non-connected state to a connected state.

22. The method according to claim 21, characterized in that The second network device sending RRC wake-up information to the terminal device includes: When the second network device determines that the cell served by the second network device meets the homomorphic task requirements, the second network device sends the RRC wake-up information to the terminal device.

23. The method according to claim 15 or 16, characterized in that The second network device is a second core network network element, the first network device is a first core network network element, the first core network element is a network device that serves the cell before the terminal device is switched, and the second core network element is a network device that serves the cell after the terminal device is switched. The homomorphic computing key and the homomorphic task information are sent through the Ng interface.

24. A communication method based on homomorphic encryption, characterized in that: include: The homomorphic management device HECF determines a homomorphic key according to the homomorphic task requirement and the homomorphic capability information of the second network device, wherein the homomorphic key is used to execute the homomorphic task in which the terminal device participates, and the homomorphic task requirement is used to indicate the parameters required to execute the homomorphic task; The HECF sends the homomorphic key and the information of the homomorphic task to the second network device; The second network device is the network device to which the terminal device is connected after switching.

25. The method according to claim 24, characterized in that The method further comprises: The HECF receives the homomorphic task requirement and the homomorphic capability information of the second network device from the second network device.

26. The method according to claim 25, characterized in that Before the HECF determines the homomorphic key according to the homomorphic task requirement and the homomorphic capability information of the second network device, the method further includes: The HECF receives indication information from the second network device, where the indication information is used to indicate that a network device to which the terminal device is connected is switched.

27. A communication method based on homomorphic encryption, characterized in that: include: The first network device receives first information from the second network device, where the first information is used to indicate that the second network device meets a homomorphic task requirement, where the homomorphic task requirement is used to indicate parameters required to execute a homomorphic task in which the terminal device participates; The first network device sends a homomorphic key and information about the homomorphic task to the second network device, where the homomorphic key and information about the homomorphic task are used to execute the homomorphic task; The first network device is a network device that the terminal device accesses before switching, and the second network device is a network device that the terminal device accesses after switching.

28. The method according to claim 27, characterized in that The second network device is a target base station, the first network device is a source base station, and the homomorphic computing key and the information of the homomorphic task are sent through the Xn interface.

29. The method according to claim 28, characterized in that Before the first network device sends the homomorphic key and the information of the homomorphic task to the second network device, the method further includes: The first network device determines the network device to which the terminal device is connected to perform switching; The first network device sends a switching request message to the second network device, where the switching request message is used to instruct the network device to which the terminal device is connected to switch; The first network device receives switching response information from the second network device, where the switching response information is used to indicate that the network device to which the terminal device is connected can be switched to the second network device; The first network device sends a switching command to the terminal device, where the switching command is used to instruct the network device to which the terminal device is connected to switch to the second network device.

30. The method according to claim 28, characterized in that Before the first network device sends the homomorphic key and the information of the homomorphic task to the second network device, the method further includes: The first network device sends a request message for obtaining a context of a terminal device to the second network device; The first network device sends the homomorphic key and the information of the homomorphic task to the second network device, including: The first network device sends a terminal device context acquisition response message to the second network device, where the terminal device context acquisition response message includes information about the homomorphic key and the homomorphic task.

31. The method according to any one of claims 27 to 30, characterized in that The second network device is a second core network network element, the first network device is a first core network network element, the first core network element is a network device that serves the cell before the terminal device is switched, and the second core network element is a network device that serves the cell after the terminal device is switched. The homomorphic computing key and the homomorphic task information are sent through the Ng interface.

32. A communication device, characterized in that: The method comprises a module or a unit for executing the method according to any one of claims 1 to 14.

33. A communication device, characterized in that: The method comprises modules or units for executing the method according to any one of claims 15 to 23.

34. A communication device, characterized in that: The method comprises modules or units for executing the method according to any one of claims 24 to 26.

35. A communication device, characterized in that: The method comprises modules or units for executing the method according to any one of claims 27 to 31.

36. A communication system, characterized in that: Includes the communication device as claimed in claim 33, the communication device as claimed in claim 34, and the communication device as claimed in claim 35.

37. A communication device, characterized in that: include: A processor, configured to execute a computer program stored in a memory so that the communication device performs the method described in any one of claims 1 to 31, and / or, through a logic circuit, so that the communication device performs the method described in any one of claims 1 to 31.

38. The communication device according to claim 37, characterized in that: The communication device further comprises the memory.

39. The communication device according to claim 37 or 38, characterized in that: The communication device further comprises: A communication interface is used to execute receiving and / or sending of the processor.

40. A computer-readable storage medium, characterized in that A computer program or instruction is stored thereon, wherein when the computer program or instruction is executed by a processor, the method as claimed in any one of claims 1 to 31 is executed.

41. A computer program product comprising instructions which, when executed on a computer, cause the method as claimed in any one of claims 1 to 31 to be performed.

42. A chip system, characterized in that: include: A processor, used to call and run a computer program or instruction from a memory so that a communication device equipped with the chip system implements a method as described in any one of claims 1 to 31.

Images