Provisioning of terminals in radio communication networks

Abstract

The invention relates to a method for provisioning a terminal (1) in a radio communication network (2), wherein, when the terminal (1) is initially connected to the radio communication network (2), the network address of a provisioning server (3) and cryptographic information for authenticating the provisioning server (3) are provided to the terminal (1) by the radio communication network (2). The invention also relates to an associated system comprising a terminal (1), a radio network (2), and a provisioning server (3).

Description

[0001] Description

[0002] Provisioning of end devices in radio communication networks

[0003] FIELD OF THE INVENTION

[0004] The invention relates to a method and a system for provisioning a terminal device in a radio communication network, wherein specific data are exchanged when the terminal device is initially connected to the radio communication network.

[0005] BACKGROUND OF THE INVENTION

[0006] 5G-based mobile networks will also be used in industrial networks in the future, such as factories or factory campuses / campus networks. To support such new deployment scenarios from a telecommunications perspective, special security procedures have already been standardized. These can be used as an alternative to or in addition to a SIM card-based (USIM / UICC) solution.

[0007] However, the required credentials must be provisioned on a mobile device (also known as an UE or Industrial 5G Device). Since different protocols and methods for credential provisioning are used in industrial environments, it is not practical to standardize a single or specific provisioning procedure for industrial use cases.

[0008] 3GPP TS23.501, section 5.30.2.10 Onboarding of UEs for SNPNs, specifies network support for credential provisioning. Provisioning occurs via the user plane. Different ways are described how a UE receives the address of the provisioning server PVS (preconfigured, when setting up the PDP context, through a discovery procedure). It is also known to identify a public key using a so-called fingerprint value, as described, for example, at https: / / en.wikipedia.org / wiki / Public_key_fingerprint. This allows a user to manually authenticate a communication partner by checking the fingerprint of the public key they are using against an expected value, without the need for digital certificates (e.g., according to X.509). This approach is supported, for example, by the ssh (secure shell) protocol.

[0009] In addition, a SubjectKeyIdentifier (SKID, see also https: / / datatracker.ietf.org / doc / html / rf c528 O#section-4.2.1.2) is known as an extension to an X.509 certificate. It contains the hash of the public key, so the value does not change when renewing a certificate for the same key pair.

[0010] Also known are enrollment protocols such as EST (RFC 7030), CMP (RFC 4210), CMC (RFC 5272), and SCEP (RFC 8894), which allow querying the fields (attributes) to be filled by the applicant in a certification request. Individual fields (attributes) or a certificate template can be provided.

[0011] Finally, the provision of values ​​for pre-populating a certification request from the Draft CMP Updates (https: / / www.ietf.org / archive / id / draft-ietf- lamps-cmp-updates-13 . html#name-new-section-531916-certif ic) is also known. This allows for querying values ​​for fields (attributes) that should be included in a certification request (CertReqTemplateContent).

[0012] SUMMARY OF THE INVENTION

[0013] The object of the invention is to provide a solution that improves and simplifies the provisioning of terminal devices in a radio communication network (also referred to as "radio network" for short), in particular in a mobile radio network used in an industrial application context (for example 5G), compared to the prior art.

[0014] The invention is based on the features of the independent claims. Advantageous developments and refinements are the subject of the dependent claims. Further features, possible applications, and advantages of the invention will become apparent from the following description.

[0015] The fundamental problem with provisioning is that the configuration must first be set up on the client (UE, end device). For example, 3GPP specifies solutions for making the address of the provisioning server (PVS) known to the UE. However, the provisioning process itself must also be protected. It is known that the user-plane protection methods available in 5G can be used for this purpose. However, these do not protect communication with the provisioning server end-to-end, and the protection is under the control of the 5G network. However, the PVS can also be managed and operated independently (e.g., at the shop floor level).

[0016] In one aspect of the invention, it is therefore proposed that the client (here: terminal) is provided with cryptographic information for authenticating the provisioning server (e.g. a public key or the subject key identifier (SKID) or the certificate of the provisioning server, or a check value formed dependent thereon, in particular a cryptographic hash value) in addition to the address of the provisioning server when connecting to the radio communication network (such as when registering / associating with a mobile network / WLAN network or when establishing a data transmission session / PDP context).

[0017] This allows the end device to authenticate the provisioning server without requiring appropriate verification credentials to be present on the device in advance. This is particularly advantageous for provisioning in closed environments (e.g., an OT factory network, an enterprise network, a private 5G network, or a campus network), since no public, global PKI infrastructure is used there. (OT = operational technology)

[0018] The invention claims a method for provisioning a terminal in a radio communication network, wherein during the initial connection of the terminal to the radio communication network

[0019] - the network address of a provisioning server and

[0020] - cryptographic information for authenticating the provisioning server is provided to the terminal device by the radio communication network.

[0021] During the "initial connection," for example, with 3GGP, the mobile device (= terminal) signals that this is an onboarding network access. "Initial" does not necessarily mean, but can also mean, "for the first time."

[0022] The advantage of the invention is that the provisioning of an (industrial) IoT device / 5G device can be better automated. Automated provisioning can also be performed in particular in different industrial environments where different provisioning protocols are used.

[0023] It is not necessary for an OT security

[0024] The infrastructure for automated provisioning must be adapted specifically for 5G devices. Cryptographically protected provisioning is enabled without the provisioning server having to authenticate itself with a digital certificate from a global, public PKI infrastructure. This supports provisioning particularly in closed OT / enterprise networks. Self-signed certificates could even be used to authenticate the provisioning server.

[0025] In a further development of the method, the cryptographic information can comprise the public key of the provisioning server, the subject key identifier (SKID) of the provisioning server, the certificate of the provisioning server, or a check value formed as a function of the certificate, in particular a cryptographic hash value.

[0026] In a further development of the method, an identifier can be provided to the terminal device during the initial connection via the radio communication network, the identifier indicating which provisioning protocol or which provisioning method is to be used.

[0027] Furthermore, a security protocol identifier can be provided to the terminal device during the initial connection via the radio communication network. The security protocol identifier specifies which security protocol or security method is to be used by the terminal device to protect the provisioning protocol. It is possible to provide both the identifier for specifying the provisioning protocol or the provisioning method and also the security protocol identifier to the terminal device during the initial connection. The security protocol identifier can specify the security protocol via which the terminal device authenticates the provisioning server using the provided cryptographic information.Furthermore, during the initial connection via the radio communication network, a crypto algorithm identifier can be provided to the terminal device. The crypto algorithm identifier specifies which cryptographic algorithm is to be used by the terminal device to authenticate the provisioning server using the cryptographic information provided by the radio communication network. Furthermore, it is possible for the provision of the cryptographic information for authenticating the provisioning server to be cryptographically protected by a user-plane protection method or, alternatively, a control-plane protection method of the radio communication network.

[0028] In a further development of the method, a configuration parameter can be provided to the terminal device during the initial connection via the radio communication network, wherein the configuration parameter specifies how the terminal device should adapt the provisioning protocol or the provisioning procedure to a predetermined application context of the terminal device.

[0029] In a further development of the method, during the initial connection, a first piece of information can be provided to the terminal device via the radio communication network, wherein the first piece of information indicates which authentication credential or which authentication method is to be used by the terminal device for authentication with the provisioning server.

[0030] In a further development of the method, a second piece of information can be provided to the terminal device by the radio communication network during the initial connection, the second piece of information specifying what is to be configured in the terminal device.

[0031] In a further development of the method, a third piece of information can be provided to the terminal device via the radio communication network during the initial connection. This third piece of information specifies how several provisioning processes are to be carried out. For example, the terminal device can be informed of which credentials and in what order they should be set up.

[0032] In a further development of the method, the radio communication network can be a 5G network and the terminal device can initially connect to a node of the 5G network.

[0033] The invention also claims a system comprising at least one terminal and a radio communication network, for provisioning the terminal in the radio communication network, wherein the radio communication network is configured, upon initial connection of the terminal to the radio communication network

[0034] - the network address of a provisioning server and

[0035] - to provide cryptographic information to the end device for authentication of the provisioning server.

[0036] In a further development of the system, the cryptographic information can comprise the public key of the provisioning server, the subject key identifier (SKID) of the provisioning server, the certificate of the provisioning server, or a check value formed as a function of the certificate, in particular a cryptographic hash value.

[0037] In a further development of the system, the radio communication network can be set up to provide the terminal with an identifier (= identifier) ​​during the initial connection, the identifier indicating which provisioning protocol or which provisioning method is to be used.

[0038] In a further development of the system, the radio communication network can be configured to provide a configuration parameter to the terminal device upon initial connection, wherein the configuration parameter specifies how the terminal device should adapt the provisioning protocol or the provisioning method to a predetermined application context of the terminal device.

[0039] In a further development of the system, the radio communication network can be configured to provide the terminal device with first information upon initial connection, the first information specifying which authentication credential or authentication method is to be used by the terminal device for authentication with the provisioning server.

[0040] In a further development of the system, the radio communication network can be configured to provide the terminal with a second piece of information during the initial connection, the second piece of information specifying what is to be configured in the terminal.

[0041] In a further development of the system, the radio communication network can be set up to provide the terminal with third information during the initial connection, the third information specifying how several provisioning processes are to be carried out.

[0042] In a further development of the system, the radio communication network can be a 5G network, wherein the 5G network has a node, and wherein the terminal device is configured to initially connect to the node.

[0043] Further features and advantages of the invention will become apparent from the following explanations of an embodiment with reference to schematic drawings.

[0044] BRIEF DESCRIPTION OF THE DRAWINGS

[0045] It shows :

[0046] FIG. 1 is a block diagram of the system,

[0047] FIG. 2 is a flow chart of the method and

[0048] FIG. 3 is a flow chart of the modified method.

[0049] DETAILED DESCRIPTION OF THE INVENTION

[0050] According to the block diagram in FIG. 1, it is disclosed that a terminal device 1 (e.g. a mobile radio device) is provided with cryptographic information for authenticating the provisioning server 3 (e.g. the public key or the subject key identifier) ​​in addition to the network address of the provisioning server 3 when initially connecting to a radio communication network 2 (e.g. registration / association with a mobile radio network / WLAN network or when establishing a data transmission session / PDP context).

[0051] (SKID), the certificate of the provisioning server 3, or a check value formed therefrom, in particular a cryptographic hash value).

[0052] This enables the end device 1 to authenticate the provisioning server 3 without the need for appropriate verification credentials to be present on the end device 1 in advance. This is particularly advantageous when provisioning in closed environments (e.g., an OT factory network, an enterprise network, a private 5G network, or a campus network), since no public, global PKI infrastructure is used in these environments.

[0053] In a further aspect, it is disclosed that the terminal device 1 is provided with an identifier (=ID) of a provisioning protocol or a provisioning method. This is advantageous because a plurality of different provisioning types can be used, e.g., OPC UA, NETCONF, RESTCONF, CMP, SCEP, EST, BRSKI. The terminal device 1 or an industrial device connected to it can thus automatically determine and execute a provisioning type.

[0054] It is possible for the terminal device 1 to provide the received provisioning information to the connected industrial device in whole or in part. This enables the connected industrial device to perform provisioning via the terminal device 1. In one variant, when transmitting the network address of the provisioning server 3 and the cryptographic information for authenticating the provisioning server 3, it can be specified whether these are intended for provisioning by the terminal device 1 or for provisioning by the industrial device connected to the terminal device 1.It is possible to provide the terminal device with a first address of a provisioning server 3 and first cryptographic information for authenticating the provisioning server 3, which the terminal device uses for provisioning, as well as a second address of a second provisioning server 3 and second cryptographic information for authenticating the second provisioning server 3, which the terminal device uses for the connected industrial device for provisioning by the industrial device. This has the advantage that both the terminal device 1 and the connected industrial device are provisioned together and thus consistently.

[0055] Additionally, a configuration parameter can be transmitted to customize the selected provisioning type. For example, with NETCONF or RESTCONF, a YANG data model can be referenced to be used for provisioning. This is advantageous because NETCONF / RESTCONF defines a variety of YANG models, some of which are standardized and some of which are vendor-specific. For a certificate management protocol such as CMP, SCEP, or EST, a reference can be made to the certificate profile and / or the crypto algorithms / cipher suites to be used for the certificate (e.g., whether RSA or EGG is used, key length).

[0056] This enables automatic adaptation of the end device to the specific provisioning variant used in a specific application context. While the transmission of certificate profiles in an enrollment protocol is known (e.g., with EST and CMP), it requires that the end device 1 be configured accordingly in advance or receive these values ​​in the context of the enrollment protocol (CMP).

[0057] This enables terminal device 1 to directly transmit, in an enrollment / provisioning protocol, the certificate profile, including predefined values, that is appropriate for the specific environment for which the enrollment / provisioning is being performed. For this purpose, the information on the certificate profile to be used, including expected values, is signaled to a terminal device via the radio network. This has the advantage that the corresponding information does not have to be configured in advance on terminal device 1, nor does an additional data exchange have to be performed in order to perform enrollment / provisioning for the target environment.

[0058] Furthermore, it is disclosed to provide the terminal 1 with first information about the authentication credential or the authentication method or the cryptographic algorithm to be used for authentication that the terminal 1 should use for authentication with the provisioning server 3. This is advantageous if a plurality of authentication credentials or authentication methods can be used on the terminal 1.

[0059] Furthermore, the terminal 1 can be provided with a second piece of information as to what exactly is to be configured (e.g. a credential for a primary authentication, a credential for a secondary authentication, a credential for a slice access authentication, or a network access configuration).

[0060] Furthermore, third information can be transmitted to terminal 1 regarding a plurality of provisioning processes to be performed. In particular, information can be transmitted to terminal 1 regarding which credentials are to be set up and in what order they are to be set up. It can also be transmitted whether there is a dependency in the application (e.g., enrollment of a generic certificate, which is then used to request additional certificates).

[0061] The information provided to the terminal device 1 can, for example, be stored in a node 2 . 1 of the 5G core, e.g. in a UDM (Unified Data Management) or AUSF (Authentication Server Function) or in an authentication server (AAA server, Default Credential Server DCS) connected to the 5G core.

[0062] Furthermore, it is possible for the information to be set in the 5G core via a network exposure interface of the 5G core. This has the advantage that an OT operator can easily store the relevant information in the 5G core regarding how the provisioning of end device 1 should be carried out via the 5G network.

[0063] Any digital certificate can be used to authenticate the provisioning server 3 without the end device 1 having to validate it in advance. This means that, for example, a self-signed certificate or a certificate issued by a local PKI infrastructure can also be used to authenticate the provisioning server 3. It is also possible to issue certificates that are only valid for a short time or a certificate that is only valid for a single provisioning process to authenticate the provisioning server 3. Such a certificate can be issued as a special provisioning server certificate for an individual end device 1 or a group of end devices 1 and set up on the provisioning server 3. This makes it easy to authenticate the provisioning server 3, which is specifically intended for provisioning a specific individual end device 1 or a specific group of end devices.

[0064] FIG. 2 shows an exemplary embodiment of the method using a flowchart. In this case, when establishing a PDP context intended for onboarding, the terminal device 1 is transmitted, in addition to the address of the provisioning server 3 (as known in the prior art), a (cryptographic) hash value of the provisioning server certificate (PVS Device Hash). Furthermore, a first identifier PVP-Id, which specifies the provisioning protocol to be used, is transmitted to the terminal device 1.

[0065] The terminal device 1 checks the validity of the TLS client certificate provided by the provisioning server 3 during the TLS handshake, i.e., the certificate used by the provisioning server 3 for authentication, for a match with the PVS cert hash value provided when establishing the PDP context. If there is no match, the provisioning process is aborted by the device, i.e., the connection to the provisioning server 3 is terminated.

[0066] Furthermore, the terminal device 1 uses the provided PVP ID to select one of several provisioning protocols or provisioning methods it supports. In the exemplary embodiment shown in FIG. 2, NETCONF is used. The provisioning server PVS establishes the connection to the device. The terminal device 1 can use the transmitted PVS device hash to verify that, in fact, only the permitted, designated provisioning server 3 can establish a TLS connection to the terminal device 1 or to the terminal device management functionality of the terminal device 1.

[0067] FIG. 3 shows a flow diagram of a further exemplary embodiment in which EST (enrollment over secure transport) is used. The PVP-Id is used to signal to the end device 1 that EST should be used to set up the client certificate. The end device establishes a TLS connection to the specified provisioning server 3 and authenticates it by checking the TLS server certificate used by the provisioning server 3 for a match with the signaled (cryptographic) hash value of the provisioning server certificate (PVS Device Hash). Further details can be found in the flow diagram in FIG. 3.

[0068] Although the invention has been illustrated and described in detail by the embodiments, the invention is not limited by the disclosed examples and other variations can be derived therefrom by a person skilled in the art without departing from the scope of the invention.

Claims

Patent claims 1. A method for provisioning an end device (1) in a radio communication network (2) , wherein, upon initial connection of the end device (1) to the radio communication network (2) - the network address of a provisioning server (3) and - cryptographic information for authentication of the provisioning server (3) is provided to the terminal device (1) by the radio communication network (2).

2. The method according to claim 1, wherein the cryptographic information comprises the public key of the provisioning server, the Subject Key Identifier (SKID) of the provisioning server (3), the certificate of the provisioning server, or a verification value formed depending on the certificate, in particular a cryptographic hash value.

3. The method according to claim 1 or 2, wherein during the initial connection via the radio communication network (2) an identifier is provided to the terminal device (1), the identifier indicating which provisioning protocol or provisioning method is to be used.

4. The method according to claim 3, wherein during the initial connection via the radio communication network (2) a configuration parameter is provided to the terminal device (1), the configuration parameter specifying how the terminal device (1) should adapt the provisioning protocol or provisioning procedure to a given application context of the terminal device (1).

5. The method according to one of the preceding claims, wherein, during the initial connection, the terminal device (1) is provided with first information via the radio communication network (2), the first information indicating which authentication credential or authentication procedure- ren is to be used by the terminal device (1) for authentication with the provisioning server (3).

6. The method according to one of the preceding claims, wherein, during the initial connection, a second piece of information is provided to the terminal device (1) via the radio communication network (2), the second piece of information indicating what is to be configured in the terminal device.

7. The method according to one of the preceding claims, wherein, during the initial connection, a third piece of information is provided to the terminal device (1) via the radio communication network (2), the third piece of information indicating how to carry out multiple provisioning operations.

8. The method according to one of the preceding claims, wherein the radio communication network (2) is a 5G network and the terminal device (1) initially connects to a node (2.1) of the 5G network.

9. A system comprising at least one terminal device (1) and a radio communication network (2) for provisioning the terminal device (1) in the radio communication network (2), wherein the radio communication network (2) is configured upon initial connection of the terminal device (1) to the radio communication network (2) - the network address of a provisioning server (3) and - to provide cryptographic information for authentication of the provisioning server (3) to the terminal device (1).

10. The system according to claim 9, wherein the cryptographic information comprises the public key of the provisioning server (3), the Subject Key Identifier (SKID) of the provisioning server, the certificate of the provisioning server (3), or a checksum formed depending on the certificate, in particular a cryptographic hash value.

11. The system according to claim 9 or 10, wherein the radio communication network (2) is configured to provide an identifier to the terminal device (1) upon initial connection, the identifier indicating which provisioning protocol or provisioning procedure is to be used.

12. The system according to claim 11, wherein the radio communication network (2) is configured to provide a configuration parameter to the terminal device (1) upon initial connection, wherein the configuration parameter specifies how the terminal device (1) should adapt the provisioning protocol or provisioning procedure to a given application context of the terminal device (1).

13. The system according to one of claims 9 to 12, wherein the radio communication network (2) is configured to provide the terminal device (1) with initial information upon initial connection, wherein the initial information specifies which authentication credential or authentication method is to be used by the terminal device (1) for authentication vis-à-vis the provisioning server (3).

14. The system according to any one of claims 9 to 13, wherein the radio communication network (2) is configured to provide the terminal device (1) with a second piece of information upon initial connection, wherein the second piece of information specifies what is to be configured in the terminal device (1).

15. The system according to any one of claims 9 to 14, wherein the radio communication network (2) is configured to provide a third piece of information to the terminal device (1) during the initial connection, wherein the third piece of information specifies how to carry out multiple provisioning operations.

16. The system according to any one of claims 9 to 15, wherein the radio communication network (2) is a 5G network, wherein the SG network has a node (2.1), and wherein the terminal device (1) is set up to initially connect to node (2.1).

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