A link-local ipv6 address auto-configuration method

Abstract

The application discloses a kind of link local IPv6 address automatic configuration methods, belong to communication technical field.The method is first obtained the position information of satellite node in constellation, forms the unique satellite node configuration triplet for each satellite node, and obtains the interface code of each interface of the satellite node;Then, based on constellation configuration, satellite node position information and spacecraft information, automatically generate link local IPv6 address;Finally, link local IPv6 address automatic configuration and uniqueness are guaranteed.The address generated by the method of the application supports accurate identification of satellite node position information, can guarantee the uniqueness of address, improve the efficiency of automatic configuration, applicable to any type of link of satellite network, including AOS link and Ethernet link.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of communication technology, and particularly relates to a link-local IPv6 address automatic configuration method. BACKGROUND

[0002] Stateless Address Autoconfiguration (SLAAC) is an important function of IPv6 network automatic configuration, which can automatically generate a link-local IPv6 address to realize the local communication ability of plug and play. The link-local IPv6 address can be used for communication between nodes on the same link (such as file sharing, routing protocol).

[0003] RFC 4291 - IPv6 Addressing Architecture defines the global structure of IPv6 address, including the link-local IPv6 address prefix FE80:: / 10, and specifies the method of generating interface identifier IID in EUI-64 format, that is, generating the last 64-bit address by extending the MAC address, such as dividing the 48-bit MAC address into two parts, inserting FFFE in the middle, and then reversing the 7th bit, that is, the U / L bit. The generated interface ID is 64-bit. Then, the interface ID is combined with the link-local prefix to form a complete IPv6 address.

[0004] RFC 4862 - IPv6 Stateless Address Autoconfiguration describes the automatic generation process of the link-local IPv6 address, which does not require Dynamic Host Configuration Protocol version 6 (DHCPv6).

[0005] RFC 7217 - A Method for Generating Semantically Opaque Interface Identifiers proposes an interface ID generation method (such as randomization, cryptographic hash) instead of EUI-64 to enhance privacy protection, but EUI-64 is still the default method for generating a link-local IPv6 address.

[0006] However, satellite network interface usually exists microwave and laser two types of links, and the link layer protocol adopts the AOS protocol of CCSDS. The AOS protocol has no MAC address, and the interface ID generated by using a random number may have a conflict, and the IP address at both ends of the same link cannot be guaranteed to be unique, which may cause an IP address conflict. If the interface IPv6 address is manually configured, since there are thousands of satellites in the LEO mega constellation network, a great amount of configuration work will be brought.

[0007] Therefore, a method for automatically generating a link-local IPv6 address without relying on a traditional SLAAC mechanism, having topological stability, automatic uniqueness guarantee and supporting any link type of a satellite constellation network is needed. SUMMARY

[0008] The present application aims at the problems of poor adaptability and insufficient automation of the existing link-local IPv6 address configuration method in a satellite network, and proposes a link-local IPv6 address automatic configuration method based on constellation configuration, satellite node position information and spacecraft identification. The generated address has clear structure, reversible mapping and global uniqueness, and can generate a unique address for each node interface without a MAC address and a random number, which is suitable for various satellite link environments and meets the needs of automatic configuration and efficient management of a large-scale constellation network.

[0009] A link-local IPv6 address automatic configuration method automatically configures a link-local IPv6 address based on constellation configuration, satellite node position information and spacecraft information, and is suitable for any type of link in a satellite network, including AOS links and Ethernet links. The constellation configuration consists of a constellation type, a constellation number and a task number. The constellation type refers to the orbit category of a satellite network and is derived from the classification of orbit types in a task planning system. The constellation number is in decimal format and consists of three digits, which is uniformly distributed by a constellation design and operation platform. The task number is in English abbreviation form and represents a specific task type, which is defined by a task scheduling system. The spacecraft information refers to a spacecraft identification, which is a unique number of a satellite spacecraft and is used to identify each satellite node in an orbit constellation. The Spacecraft_ID distributed by the CCSDS organization is preferably used as the source of the unique spacecraft identification. The method specifically includes the following steps:

[0010] S1, obtaining the position information of the satellite node in the constellation, including the shell_id, orbit_id, and sat_id in the orbit plane, forming a unique satellite node configuration triple [shell_id, orbit_id, sat_id] for each satellite node, and obtaining the interface code dir of each interface of the satellite node, which is used to uniquely identify different interfaces of the satellite, including the same-orbit satellite interface, different-orbit satellite interface, and inter-layer interface;

[0011] S2, automatically generating a link-local IPv6 address based on the constellation configuration, satellite node position information, and spacecraft information:

[0012] S2.1 The total length of the link-local IPv6 address is 128 bits, divided into 8 fields, each field occupies 16 bits, and named as field 1~field 8 in turn; field 1~field 4 is fixed as the link-local IPv6 address prefix, and field 5~field 8 is the link-local interface identifier IID;

[0013] S2.2 Generate the link-local IPv6 address prefix: the values of field 1~field 4 are fixed as FE80:0:0:0;

[0014] S2.3 Generate the link-local interface identifier IID:

[0015] Field 5 stores the hash value of the constellation configuration, which consists of constellation type, constellation number, and task number, connected in order by hyphen "-" to form a constellation configuration identification string "constellation type-constellation number-task number", and then calculated by the standard hash function CRC-16 to get a 16-bit hash value, which is filled into field 5;

[0016] Field 6 stores the shell_id, orbit_id, and sat_id in the orbit plane; the interface code dir is stored in the last 4 bits of field 8;

[0017] Field 7 and field 8 store the spacecraft information, and Spacecraft_ID is filled in the remaining fields of field 7 and field 8 by adding 0 to the right side to 28 bits, thereby generating the link-local interface identifier IID;

[0018] S2.4 Generate the link-local IPv6 address:

[0019] Connect the link-local IPv6 address prefix with the link-local interface identifier IID to generate the link-local IPv6 address interface_ip.

[0020] S2.5 interface_ip maps satellite node configuration triplet [shell_id, orbit_id, sat_id] and interface code dir:

[0021] interface_ip can map satellite node location information and interface code dir, by extracting the first two bits of field 6 in interface_ip, the orbit layer number shell_id of the satellite node can be obtained, by extracting the last p bits of field 6 in interface_ip, the satellite node number sat_id in the orbit plane of the satellite node can be obtained, by extracting the middle 14-p bits of field 6 in interface_ip, the orbit number orbit_id of the satellite node can be obtained, by extracting the last 4 bits of field 8 in interface_ip, the interface code of each interface of the satellite node can be obtained.

[0022] Therefore, the satellite node configuration triplet [shell_id, orbit_id, sat_id] and interface code dir of the satellite node can be mapped by the link-local IPv6 address, and the location and interface information of the satellite node can be accurately identified, the constellation configuration can be obtained by extracting field 5, and the spacecraft related information can be obtained by extracting field 7 and the remaining part of field 8.

[0023] S3, link-local IPv6 address automatic configuration and uniqueness guarantee:

[0024] When one of the satellite node cold start, interface state change and orbit adjustment occurs, the link-local IPv6 address automatic configuration method in step S2 is automatically performed, interface_ip described in step S2.4 is configured to the link-local interface, and is directly marked as preferred, the IPv6 network protocol stack duplicate address detection process is omitted, and the interface_ip can be subsequently used for neighbor discovery and control plane configuration neighbor cache, and can directly participate in IPv6 routing protocol communication;

[0025] S3.1 address state life cycle management

[0026] The link-local IPv6 address is generated based on the constellation configuration, satellite node configuration ternary [shell_id, orbit_id, sat_id] and the spacecraft identifier, has persistence and stability; the system regularly detects the neighbor reachability, when the detection result shows that the neighbor is unreachable, the system will mark it as Unreachable state, at this time, if one of the link state change, orbit adjustment and satellite node restart event occurs, the system will automatically re-execute the address generation and configuration process, quickly restore the neighbor reachability, has good autonomy and fast recovery ability.

[0027] S3.2 Link-local IPv6 address uniqueness analysis

[0028] The link-local IPv6 address generated in step S2 is composed of the following two parts:

[0029] The address prefix part, i.e. field 1~field 4: fixed as FE80:0:0:0, used to identify the link-local scope;

[0030] The interface identifier part, i.e. field 5~field 8: contains the constellation configuration, satellite node configuration ternary [shell_id, orbit_id, sat_id], interface code dir and spacecraft information;

[0031] From the result design level, through the unique position information of each satellite node, constellation configuration and spacecraft identifier, each interface is unique in the local node, prevents link-local interface identifier IID conflict, ensures the uniqueness of the link-local IPv6 address.

[0032] Advantages

[0033] 1. The application provides a method for automatically configuring the uniqueness of link-local IPv6 address according to the satellite node position information and spacecraft information, by embedding the orbit layer number, orbit number, satellite node number in the orbit, interface, constellation configuration and spacecraft identifier of the satellite node, a unique interface identifier is constructed, ensuring that the link-local IPv6 address corresponding to each interface of each node is unique in the whole network, saving the traditional IPv6 network protocol stack duplicate address detection, reducing the protocol overhead, improving the configuration efficiency and reliability, and supporting the bidirectional mapping of address to node information, improving the management ability of large-scale satellite network.

[0034] 2、The application does not need to depend on MAC address and management server, the satellite node can automatically generate link local IPv6 address when the state changes, meets the plug and play demand of large-scale constellation network, combines the neighbor unreachable detection mechanism, automatically reconfigures the address and recovers the communication when one of the link state changes, orbit adjustment and satellite node restart event occurs, has good autonomy and fault tolerance, is suitable for various link types including AOS protocol, laser link and Ethernet, solves the problem of address automatic generation limitation in MAC environment. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is a link local IPv6 address automatic configuration overall scheme;

[0036] Figure 2 is link local interface identifier IID automatic generation;

[0037] Figure 3 is link local IPv6 address automatic generation;

[0038] Figure 4 is link local IPv6 address automatic generation example. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical scheme and advantages of the application more clear, taking two-layer 10x10 low-orbit satellite constellation network composed of 200 LEO satellite nodes as an example, taking 100 LEO satellite nodes of one layer 10x10 close to the ground as an example, the embodiments of the application are described in detail in combination with the drawings. The embodiments are implemented on the premise of the technical scheme of the application, and give detailed implementation mode and specific operation process. The specific examples described herein are only used to explain the application, but the protection scope of the application is not limited to the following embodiments.

[0040] S1, the position information of the satellite node in the constellation is acquired, including orbit layer number shell_id, orbit number orbit_id, satellite node number sat_id in the orbit plane, forming a unique satellite node configuration triple [shell_id, orbit_id, sat_id] for each satellite node, and the interface code dir of each interface of the satellite node is acquired, the interface code is used for uniquely identifying different interfaces of the satellite, including inter-orbit satellite interface, inter-orbit satellite interface and inter-layer interface;

[0041] In this embodiment, a layer of 100 LEO satellite nodes of 10x10 close to the ground is defined as the first layer, and a layer of LEO satellite nodes away from the ground is defined as the second layer. The position information of the satellite nodes in the constellation and the interface code dir of each interface are obtained. Each satellite node in the first layer has six interfaces, including two same-orbit satellite interfaces int-1 and int-2, two different-orbit satellite interfaces int-3 and int-4, and two inter-layer interfaces int-up and int-down. The same-orbit satellite interface includes the forward orbit direction interface int-1 and the reverse orbit direction interface int-2, and the interface code dir is 1 and 2, respectively. The different-orbit satellite interface includes the left orbit direction interface int-3 and the right orbit direction interface int-4, and the interface code dir is 3 and 4, respectively. The inter-layer interface includes the interface int-up connecting the upper orbit and the interface int-down connecting the ground, and the interface code dir is 5 and 6, respectively. The position information of part of the satellite nodes in the constellation and the interface code are listed in Table 1:

[0042] Table 1 Position information of part of the satellite nodes and interface code

[0043]

[0044] S2, based on the constellation configuration, the satellite node position information and the spacecraft information, automatically generating a link-local IPv6 address:

[0045] S2.1 The total length of the link-local IPv6 address is 128 bits, which is divided into 8 fields, each field occupies 16 bits, and is named field 1~field 8 in turn. Field 1~field 4 is fixed as the link-local IPv6 address prefix, and field 5~field 8 is the link-local interface identifier IID, as shown in the following figure: Figure 1

[0046] S2.2 Generate link-local IPv6 address prefix: the values of field 1~field 4 are fixed as FE80:0:0:0;

[0047] S2.3 Generate link-local interface identifier IID:

[0048] Map the satellite node configuration triple [shell_id, orbit_id, sat_id] to the link-local interface identifier IID:

[0049] As shown in the following figure: Figure 2 ​As shown, the link-local interface identifier IID is a 64-bit address, the first two 16 bits of the IID correspond to the 5th and 6th fields of the link-local IPv6 address respectively, and the last two 16 bits correspond to the 7th and 8th fields of the link-local IPv6 address respectively. The 5th field stores the hash value of the constellation configuration, which consists of the constellation type, constellation number, and task number, which are sequentially connected by a hyphen “-” to form a constellation configuration identification string “constellation type-constellation number-task number”, and then a 16-bit hash value is obtained by performing hash calculation on the string by using a standard hash function CRC-16, and filled into the 5th field; in this embodiment, LEO represents the constellation type, 001 represents the constellation number, and COM represents the task number, which are sequentially connected by a hyphen “-” to form a constellation configuration identification string “LEO-001-COM”, and then compressed to 16 bits by using a standard hash function CRC-16, and filled into the 5th field, in this embodiment, abcd is filled into the 5th field, which is only illustrative, and the actual value is generated according to system configuration;

[0050] The 6th field stores the shell_id, orbit number orbit_id, and satellite node number sat_id in the orbit plane; wherein the bit width of shell_id is 2 bits, the bit width of orbit_id is 6 bits in this embodiment, and the bit width of sat_id is 8 bits. The interface code dir is stored in the last 4 bits of the 8th field; the remaining fields of the 8th field and the 7th field store the spacecraft information, the remaining fields of the 8th field are set to 0 in this embodiment, and 1a2b is used as the 7th field to represent the spacecraft information, which is only illustrative, and the actual value is generated according to system configuration. Thus, the link-local interface identifier IID is generated;

[0051] For example, the satellite node configuration triple [shell_id, orbit_id, sat_id] is [1, 3, 5], and the interface code dir is 1, 2, 3, 4, 5, 6,

[0052] The shell_id is converted to hexadecimal and filled into the first 2 bits of the 6th field: 01;

[0053] The orbit_id is converted to hexadecimal and filled into the middle 6 bits of the 6th field: 000011;

[0054] The sat_id is converted to hexadecimal and filled into the last 8 bits of the 6th field: 00000101;

[0055] The dir is converted to hexadecimal and filled into the last 4 bits of the 8th field: 0001, 0010, 0011, 0100, 0101, 0110;

[0056] Thus field 6 is filled in with 0100001100000101, corresponding to 0x4305 in hexadecimal, field 6 is filled in with 4305, the IID of interface j of this satellite is abcd:4305:1a2b:j, where j takes value in the range of dir, as shown in the following table 3. Figure 4

[0057] The link-local interface identifier IID is shown in table 2.

[0058] Table 2 Link-local interface identifier IID

[0059]

[0060] For example, the satellite node with constellation triplet [1, 3, 5] has six interfaces: int-1 and int-2 for inter-orbit satellite interface, int-3 and int-4 for inter-constellation satellite interface, int-up and int-down for inter-layer interface, corresponding to dir 1, 2, 3, 4, 5, 6 respectively. According to the above link-local interface identifier IID generation method, the link-local interface identifier IID of the six interfaces of this satellite node is shown in table 3.

[0061] Table 3 Link-local interface identifier IID of satellite node at [1, 3, 5]

[0062]

[0063] S2.4 Generating link-local IPv6 address:

[0064] The link-local IPv6 address prefix is concatenated with the link-local interface identifier IID, thus generating the link-local IPv6 address interface_ip, as shown in the following table 4. Figure 3

[0065] The link-local IPv6 address interface_ip is shown in table 4.

[0066] Table 4 Link-local IPv6 address interface_ip

[0067]

[0068] For example, the satellite node with constellation triplet [1, 3, 5] has six interfaces: int-1 and int-2 for inter-orbit satellite interface, int-3 and int-4 for inter-constellation satellite interface, int-up and int-down for inter-layer interface, corresponding to dir 1, 2, 3, 4, 5, 6 respectively. According to the above link-local interface identifier IID generation method, the link-local interface identifier IID of the six interfaces of this satellite node is shown in table 3. Figure 4

[0069] Table 5 Link-local IPv6 address of each interface of satellite node at [1, 3, 5]​​​

[0070]

[0071] S2.5 interface_ip maps the satellite node configuration triplet [shell_id, orbit_id, sat_id] and interface code dir:

[0072] For example, the link-local IPv6 address interface_ip of a satellite node is FE80:0:0:0:abcd:460A:1a2b:1:

[0073] The first 2 bits of field 6 can be obtained:

[0074]

[0075] The middle 6 bits of field 6 can be obtained:

[0076]

[0077] The last 8 bits of field 6 can be obtained:

[0078]

[0079] The configuration triplet of this satellite node is [1, 6, 10];

[0080] The last 4 bits of field 8 can be obtained as the interface is in-orbit and the running direction of the interface is in the same orbit.

[0081] Therefore, according to interface_ip, the unique satellite node configuration triplet [shell_id, orbit_id, sat_id] and interface code dir of the satellite node in the network topology can be obtained.

[0082] S3, Link-local IPv6 address auto-configuration and uniqueness guarantee

[0083] When one of the satellite node cold start, interface state change and orbit adjustment occurs, the link-local IPv6 address auto-configuration method in step S2 is automatically executed, and the interface_ip described in step S2.4 is configured to the link-local interface, which is directly marked as preferred, and the traditional IPv6 network protocol stack duplicate address detection process is omitted.

[0084] For example, the configuration triplet of the satellite node is [1, 3, 5], and the link-local IPv6 addresses corresponding to the 6 interfaces of the node are defined in S2 as listed in Table 4. The addresses in Table 4 will be written into the interface address list, as listed in Table 6:

[0085] Table 6 [1,3,5] Satellite node interface address list

[0086]

[0087] This address can be used for neighbor discovery and control plane configuration neighbor cache, and can also directly participate in IPv6 routing protocol communication including OSPFv3, Babel, BGP.

[0088] S3.1 Address state life cycle management

[0089] The link-local IPv6 address generated by the method is generated based on the constellation configuration, satellite node configuration triple [shell_id, orbit_id, sat_id] and the spacecraft identifier, and has persistence and stability; the system periodically detects the neighbor unreachable, and when the detection result shows that the neighbor is unreachable, the system marks it as Unreachable state, at this time, if one of the link state change, orbit adjustment and satellite node restart event occurs, the system will automatically re-execute the address generation and configuration process, quickly recover the neighbor reachability, and has good autonomy and fast recovery ability.

[0090] S3.2 Link-local IPv6 address uniqueness analysis

[0091] The link-local IPv6 address generated in step S2 is composed of the following two parts:

[0092] The address prefix part, i.e. field 1~field 4: fixed as FE80:0:0:0, used to identify the link-local scope.

[0093] The interface identifier part, i.e. field 5~field 8: contains the constellation configuration, satellite node configuration triple [shell_id, orbit_id, sat_id], interface code dir and spacecraft information.

[0094] Each satellite has a unique configuration triple [shell_id, orbit_id, sat_id] in the constellation; each interface code dir is unique within the local node; each satellite has a unique spacecraft identifier; each constellation has a unique constellation configuration. Therefore, from the structural design level, the possibility of IID conflict is prevented, and the link-local IPv6 address meets the global uniqueness.

Claims

1. A link-local IPv6 address automatic configuration method, characterized in that: Automatically configure link-local IPv6 addresses based on constellation configuration, satellite node location information, and spacecraft information, applicable to any type of satellite network link, including AOS links and Ethernet links. The constellation configuration consists of a constellation type, a constellation number, and a mission number. The constellation type refers to the orbital category of the satellite network and is derived from the classification of orbital types in the mission planning system. The constellation number is in decimal format, consisting of three digits and uniformly assigned by the constellation design and operation and maintenance platform. The mission number is in English abbreviation form, indicating the specific mission type and is defined by the mission scheduling system. The spacecraft information refers to the spacecraft identifier, which is a unique number of a satellite-type spacecraft and is used to identify each satellite node in the orbital constellation. The method comprises the following steps: S1. Obtain the location information of the satellite node in the constellation, including the orbital layer number shell_id, orbit number orbit_id, and satellite node number sat_id in the orbital plane. Form a unique satellite node configuration triplet [shell_id, orbit_id, sat_id] for each satellite node, and obtain the interface code dir of each interface of the satellite node. The interface code is used to uniquely identify different interfaces of the satellite, including interfaces between satellites in the same orbit, interfaces between satellites in different orbits, and inter-layer interfaces. S2, automatically generates link-local IPv6 addresses based on constellation configuration, satellite node location information, and spacecraft information; S3, automatic configuration and uniqueness guarantee of link-local IPv6 addresses; The specific process of step S2 is as follows: S2.1 The link-local IPv6 address is 128 bits long and is divided into eight fields, each of which occupies 16 bits. These fields are named Field 1 through Field 8. Fields 1 through 4 are fixed as the link-local IPv6 address prefix, and Fields 5 through 8 are the link-local interface identifier (IID). S2.2 Generate a link-local IPv6 address prefix: fix the values ​​of fields 1 to 4 to FE80:0:0:0; S2.3 Generate a link-local interface identifier IID: Field 5 stores the hash value of the constellation configuration. The constellation configuration consists of the constellation type, constellation number, and mission number. These three are sequentially connected with a hyphen "-" to form the constellation configuration identification string "constellation type-constellation number-mission number". This string is then hashed using the standard hash function CRC-16 to obtain a 16-bit hash value, which is entered into Field 5. Field 6 stores the orbital layer number shell_id, orbit number orbit_id, and satellite node number sat_id in the orbital plane; the interface code dir is stored in the last 4 bits of field 8; The remaining fields of field 7 and field 8 store spacecraft information, and the Spacecraft_ID is padded on the right with 0 to 28 bits to fill in the remaining fields of field 7 and field 8 to generate the link local interface identifier IID; S2.4 Generate a link-local IPv6 address: Concatenate the link-local IPv6 address prefix with the link-local interface identifier IID to generate the link-local IPv6 address interface_ip; S2.5 interface_ip maps the satellite node configuration triple [shell_id, orbit_id, sat_id] and the interface code dir.

2. The link-local IPv6 address automatic configuration method according to claim 1, characterized in that: The spacecraft information described above uses the Spacecraft_ID assigned by the CCSDS organization as the source of the unique spacecraft identification.

3. The link-local IPv6 address automatic configuration method according to claim 1, wherein: The interface_ip mapping described in step S2.5 to the satellite node configuration triple [shell_id, orbit_id, sat_id] and the interface code dir can reflect the satellite node configuration triple [shell_id, orbit_id, sat_id] and the interface code dir of the satellite node in the constellation from the link-local IPv6 address, that is, it can parse the orbital layer number shell_id, orbit number orbit_id, satellite node number sat_id in the orbital plane, and interface information of the satellite node corresponding to any link-local IPv6 address.

4. The link-local IPv6 address automatic configuration method according to claim 1, wherein: The specific process of step S3 is as follows: When a satellite node cold starts, changes its interface status, or adjusts its orbit, the link-local IPv6 address autoconfiguration method in step S2 is automatically executed. The interface_ip in step S2.4 is assigned to the link-local interface and directly marked as preferred. The IPv6 network protocol stack duplicate address detection process is omitted. The interface_ip can then be used for neighbor discovery and control plane configuration of the neighbor cache, and can also directly participate in IPv6 routing protocol communications. S3.1 Address state lifecycle management: The link-local IPv6 address is generated based on the constellation configuration, the satellite node configuration triple [shell_id, orbit_id, sat_id], and the spacecraft identifier. The system regularly performs neighbor unreachability checks on neighbors. When the test result indicates that the neighbor is unreachable, the system marks it as unreachable. At this time, if any of the link status changes, orbit adjustments, and satellite node restart events occur, the system will automatically re-execute the address generation and configuration process to quickly restore neighbor reachability. S3.2 Link-local IPv6 address uniqueness analysis: The link-local IPv6 address generated in step S2 consists of the following two parts: The address prefix, that is, fields 1 to 4, is fixed at FE80:0:0:0 and is used to identify the link-local scope. The interface identifier part, i.e., fields 5 to 8, includes the constellation configuration, satellite node configuration triplet [shell_id, orbit_id, sat_id], interface code dir, and spacecraft information.

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