Satellite network SRv6 head compression conversion method

Abstract

The invention discloses a satellite network SRv6 header compression conversion method, relates to the field of space-ground convergence network communication, and aims to solve the problem of seamless compatible intercommunication between a satellite network based on satellite label routing switching and a ground standard SRv6 network. According to the scheme, end-to-end SRv6 path arrangement between a satellite network and a ground SRv6 network can be realized, the transmission overhead of a standard SRv6 packet in the satellite network is reduced, an SRH head sinks below a network layer, the safety protection of a whole IP layer is realized, the scheme can be continuously compatible with a standard SRv6 technology, and the scheme is particularly suitable for a satellite network system with high safety requirement and limited bandwidth.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of space-ground integrated network communication, and in particular to a satellite network SRv6 header compression conversion method. BACKGROUND

[0002] With the hot development of satellite Internet, space-ground network integration has gradually become the development trend of satellite networks. At present, the SRv6 routing exchange technology in the ground network is gradually mature, and ground operators and enterprise networks have gradually used SRv6 routing technology to build their own interconnected networks. How the satellite network supports the ground SRv6 network and realizes the integration and interconnection of space-ground networks is a technical problem to be solved. There are some problems in directly using the SRv6 technology stack to realize the routing exchange system in the satellite network. Because the standard SRH header encapsulation overhead of SRv6 is large, the transmission efficiency is too low for the satellite network with limited air link bandwidth; on the other hand, since the satellite network link is a wireless link, the security is poor when exposed in space, and the on-board router in the satellite network runs in space with high value and cannot be quickly replaced, so if it is damaged due to network attack, it will cause great loss, on the other hand, for some special networks, using open standard SRv6 packets is also easy to be cracked by attackers and cause security risks. The current public information shows that there is no SRv6 adaptation technology suitable for satellite networks that has been concerned and researched by the academic circle. SUMMARY

[0003] The present application discloses a satellite network SRv6 header compression conversion method, device and forwarding system, relating to the field of space-ground integrated network communication, aiming to solve the problem of seamless compatibility and interconnection between satellite networks based on satellite label routing exchange and ground standard SRv6 networks.

[0004] In order to achieve the above-mentioned application purpose, the technical scheme adopted by the present application is as follows:

[0005] A satellite network SRv6 header compression conversion method, comprising the following steps:

[0006] (1) Defining a label layer between the link layer and the network layer of the satellite network data frame, the label layer adopts a TLV (Type, Length, Value) structure, wherein the type part represents the next protocol type, which is the protocol type encapsulated by the network layer; the length part represents the length of the TLV structure; the value part includes a label length field, a label stack depth field and a label stack field, the label length field represents the length of the current single SRv6 SID after compression, the label stack depth field represents the position of the current top label in the label stack, and the label stack field fills in the label stack value after SRv6 SRH compression;

[0007] (2) Each node of the satellite network runs an extended SRv6 routing protocol supporting satellite label distribution, and the satellite terminal or the ground station gateway interacts with the ground-side device using the standard SRv6 routing protocol to obtain the format of the current SRv6 SID, including the format and length of the current SRv6 Block, Node ID and Function ID;

[0008] (3) After the satellite terminal or the ground station gateway receives the standard SRv6 packet at the ground-side interface, it is determined whether the SRv6 packet carries an SRH header; if not, the Node ID and the Function ID are extracted from the destination IP address field of the IPv6 basic header according to the format definition of the current SRv6 SID, and are encapsulated in the label layer; if the SRv6 packet carries an SRH header, the Node ID and the Function ID field in each SRv6 SID in the SRv6 SRH header in the current packet are extracted, assembled into a label stack and encapsulated in the label layer; at the same time, the SRv6 SRH header in the current packet is deleted, the current packet is reassembled, encapsulated into a gigabit satellite link layer frame format, and sent to the satellite-side export;

[0009] (4) After the satellite node receives the packet, the top label in the label layer is used to look up the satellite label forwarding table for forwarding; after the satellite terminal or the ground station gateway at the receiving end receives the SRv6 packet encapsulating the label layer, the label stack depth field of the label layer is checked; if the label stack depth has reached the bottom of the stack, the label layer is deleted and the IPv6 packet is reassembled; if the label stack depth has not reached the bottom of the stack, the label layer is restored to a standard SRv6 SRH header; then the packet is queried in the local IPv6 routing table and sent to the ground-side export.

[0010] The label layer is defined in a TLV structure and supports cascading extension, and can provide extension support for conversion and adaptation with other SRv6 headers.

[0011] In step (2), the format of the current SRv6 SID, including the format and length of the current SRv6 Block, Node ID and Function ID, can also be configured through separate control or management signaling.

[0012] The end-to-end SRv6 SRH path for interworking between the ground network and the satellite network needs to be configured by a global SDN controller for the head node. The global SDN controller can obtain the link state and topology information of the ground network and the satellite network, calculate the end-to-end optimal SRv6 path based on the global perspective, and configure the SRH of any head node of the ground network and the satellite network.

[0013] Compared with the background art, the present application has the following advantages:

[0014] The application can realize end-to-end SRv6 path orchestration between a satellite network and a ground SRv6 network, reduce the transmission overhead of a standard SRv6 packet in the satellite network, sink the SRH header below the network layer, realize security protection of the entire IP layer, and can continuously be compatible with the standard SRv6 technology, and is particularly suitable for a satellite network system with high security requirements and limited bandwidth. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 A basic principle block diagram of a satellite network SRv6 header compression conversion method in an embodiment of the application.

[0016] Figure 2 An application scenario example diagram in an embodiment of the application. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the application more clear, the application is further described in detail below.

[0018] A satellite network SRv6 header compression conversion method, Figure 1 The basic principle of the satellite network SRv6 compression forwarding method is described. When the SRv6 data packet of the ground network enters the satellite network through the satellite terminal or the ground station gateway, the SRv6 SRH header is compressed and converted, the SRH header is converted into a satellite label layer, is encapsulated between the link layer and the network layer, the satellite network performs label routing forwarding according to the converted satellite label layer at each node, and when the SRv6 data packet lands and leaves the satellite network, the standard SRv6 data packet is restored by the satellite terminal or the ground station gateway, and is sent to the ground user.

[0019] Figure 2A typical embodiment of SRv6-based fusion interworking of ground network and satellite network is given, wherein the ground network includes a user H1, ground routers R1-R6, the satellite network includes satellite terminals T1-T3, satellite routers S1-S4, and a satellite user H1. The satellite routers are connected through inter-satellite links, the satellite routers and the satellite terminals are connected through satellite-ground links, and the ground routers R5 and R6 are connected to the satellite terminal T1. The ground network is constructed based on SRv6 routing exchange technology, and the satellite network is constructed based on satellite label routing exchange technology. A global SDN controller can perform end-to-end arrangement on paths of the ground network and the satellite network. Taking communication between the ground network user H1 and the satellite user H2 as an example, the global SDN controller arranges a communication path from H1 to H2 as R2-R6-S2-T2, and the data sent by H1 is inserted with an SRH header (R2-R6-S2-T2) at R1. The data packet is forwarded in the ground network according to the path specified by the SRH header, reaches the satellite terminal T1 as an entry terminal of the satellite network, and is compressed and converted by the satellite terminal into a satellite label layer. After the satellite label layer is encapsulated in the satellite link layer, the data packet is forwarded in the satellite network through label routing. When the data packet leaves the satellite network from the satellite terminal T2, the satellite terminal T2 restores the data packet into a standard SRv6 data packet, performs SRH header popping and IPv6 routing table lookup, and forwards the data packet to the satellite user H2.

[0020] Specifically, the method comprises the following steps:

[0021] (1) Defining a label layer between the link layer and the network layer of a satellite network data frame, wherein the label layer adopts a TLV (Type, Length, Value) structure, the type part of the TLV structure represents a next protocol type, which is a protocol type encapsulated by the network layer; the length part represents a length of the TLV structure; and the value part includes a label length field, a label stack depth field, and a label stack field, the label length field represents a compressed length of a current single SRv6 SID, the label stack depth field represents a position of a top label in a label stack, and the label stack field fills a label stack value compressed from an SRv6 SRH;

[0022] (2) Running an SRv6 routing protocol extended to support satellite label distribution at each node of the satellite network, and performing interaction between a satellite terminal or a ground station gateway and a ground-side device through a standard SRv6 routing protocol to obtain a format of a current SRv6 SID, including a format and a length of a current SRv6 Block, a Node ID, and a Function ID;

[0023] (3) The satellite terminal or the ground station gateway receives the standard SRv6 packet on the ground side interface, judges whether the SRv6 packet carries the SRH header, if not, extracts the Node ID and the Function ID from the destination IP address field of the IPv6 basic header according to the format definition of the current SRv6 SID, and encapsulates them in the label layer, if carries the SRH header, extracts the Node ID and the Function ID field in each SRv6 SID from the SRv6 SRH header in the current packet, assembles into a label stack and encapsulates them in the label layer, meanwhile, deletes the SRv6 SRH header in the current packet, reassembles the current packet, encapsulates it into a satellite link layer frame format of gigabit, and sends it to the satellite side export;

[0024] (4) The satellite node receives the data packet, and forwards according to the top label in the label layer and the satellite label forwarding table; the satellite terminal or the ground station gateway receives the SRv6 data packet encapsulated with the label layer, checks the label stack depth field of the label layer, if the label stack depth has reached the bottom, deletes the label layer and reassembles it into an IPv6 data packet, if the label stack depth has not reached the bottom, restores the label layer into a standard SRv6 SRH header, then queries the local IPv6 routing table and sends it to the ground side export.

[0025] Wherein, the label layer adopts TLV structure definition, supports cascading extension, and can provide extension support for conversion and adaptation with other SRv6 header.

[0026] Wherein, the type value of the first tlv is identified in the satellite link layer frame, and the type value of the last TLV identifies the data type of the payload.

[0027] Wherein, the format of the current SRv6 SID in step (2) includes the current SRv6 Block, the format and length of the Node ID and the Function ID, and other information, which can also be configured through separate control or management signaling.

[0028] Wherein, the end-to-end SRv6 SRH path for interworking between the ground network and the satellite network needs to be configured by the global SDN controller for the head node, the global SDN controller can obtain the complete link state and topology information of the ground network and the satellite network, calculate the end-to-end optimal SRv6 path based on the global perspective, and configure the SRH of any head node of the ground network and the satellite network.

[0029] The above is only a preferred embodiment of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for converting SRv6 header compression, characterized in that, Comprise the following steps: (1) define a label layer between the link layer and network layer of the satellite network data frame, which adopts TLV structure, i.e. type, length, value; Wherein the type part indicates the next protocol type, which is the protocol type encapsulated by the network layer; the length part indicates the length of the TLV structure; the value part includes a label length field, a label stack depth field and a label stack field, the label length field indicates the length of the current single SRv6 SID after compression, the label stack depth field indicates the position of the current top label in the label stack, and the label stack field fills in the value of the label stack after SRv6 SRH compression; (2) each node of the satellite network runs an extended SRv6 routing protocol supporting satellite label distribution, and the satellite terminal or ground station gateway interacts with the ground side device using the standard SRv6 routing protocol to obtain the format of the current SRv6 SID, including the format and length of the current SRv6 Block, Node ID and Function ID; (3) after the satellite terminal or ground station gateway receives the standard SRv6 packet at the ground side interface, it judges whether the SRv6 packet carries the SRH header; if not, the Node ID and Function ID are extracted from the destination IP address field of the IPv6 basic header according to the format definition of the current SRv6 SID; And encapsulate them in the label layer; if it carries the SRH header, the Node ID and Function ID fields in each SRv6 SID are extracted from the SRv6 SRH header in the current data packet, assembled into a label stack and encapsulated in the label layer; at the same time, the SRv6 SRH header in the current data packet is deleted, the current data packet is reassembled, encapsulated into a gigabit satellite link layer frame format, and sent to the satellite side outlet; (4) after the satellite node receives the data packet, it looks up the satellite label forwarding table according to the top label in the label layer for forwarding; after the satellite terminal or ground station gateway at the receiving end receives the SRv6 data packet encapsulated with the label layer, it checks the label stack depth field of the label layer; 2. The method of claim 1, wherein, If the label stack depth has reached the bottom of the stack, delete the label layer and reassemble it into an IPv6 data packet; if the label stack depth has not reached the bottom of the stack, restore the label layer to a standard SRv6 SRH header; then query the local IPv6 routing table and send it to the ground side outlet. 3.The satellite network SRv6 header compression conversion method according to claim 1, characterized in that, The label layer adopts TLV structure definition and supports cascading extension, providing extension support for conversion and adaptation with other SRv6 headers. Step (2) the format of the current SRv6 SID includes the format and length information of the current SRv6 Block, Node ID and Function ID, which is configured through separate control or management signaling.

4. The method of claim 1, wherein, The end-to-end SRv6 SRH path for interworking between the ground network and the satellite network needs to be configured by a global SDN controller for the head node, the global SDN controller obtains all link states and topology information of the ground network and the satellite network, calculates an end-to-end optimal SRv6 path based on a global perspective, and is capable of SRH arrangement configuration for any head node of the ground network and the satellite network.

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