Automatic domain division method based on OSPF protocol

Abstract

The invention provides an automatic domain division method based on an OSPF protocol, and the method comprises the steps: carrying out the region division of an AS, obtaining a backbone region and a non-backbone region, distributing zero-value OSPF region numbers to all interconnection ports of a router in the backbone region, enabling one non-backbone region to correspond to one non-zero-value OSPF region number, enabling the non-zero-value OSPF region numbers to be different, and enabling all the non-zero-value OSPF region numbers to be different from one another. For each non-backbone area boundary router, a zero-value OSPF area number is allocated to an interconnection port connected with the backbone area boundary router, a non-zero-value OSPF area number is allocated to an interconnection port connected with the router in the non-backbone area, and non-zero-value OSPF area numbers are allocated to interconnection ports of all the routers in the non-backbone area; after the OSPF area numbers are distributed to all the interconnection ports, all the interconnection ports are arranged in the same network segment and announced to the OSPF areas where the interconnection ports are located, the situation of repeated configuration can be avoided, and the stability and efficiency of automatic domain division are improved.

Description

Technical Field

[0001] The invention relates to the technical field of autonomous system network area division, in particular to an automatic domain division method based on OSPF protocol. Background Art

[0002] An autonomous system (AS) is a group of network units that exchange routing information with each other through a unified routing protocol. OSPF is a typical link-state routing protocol that collects link state information in the network to build a topology map of the entire AS and calculates the shortest path tree based on the topology map to determine the best route for each destination.

[0003] In the prior art, the OSPF routing autonomous domain division method and system for low-orbit satellite networks with application number 202310229286.X provides the following technical solutions to overcome the problem of improper regional division: obtain the network topology structure, and use the OSPF convergence model to predict the size of the balanced partition of the network; use the size of the balanced partition as the partition constraint, and select the backbone node in the network according to the node centrality and link bandwidth, and set the area_id field of the backbone node to 0 to obtain the backbone area; use the community detection algorithm based on graph data to divide the network outside the backbone area into several non-backbone areas, and the size of the non-backbone area is equal to the size of the balanced partition; optimize the non-backbone area until there is no disconnected area between the backbone area and the non-backbone area, and output the non-backbone area; select the nodes in the backbone area that meet the preset conditions as the boundary nodes, and update the node_type field of the boundary node to ABR to obtain the final OSPF routing autonomous domain division scheme. The advantages of this method are that the traffic between regions is small and the connectivity between the backbone area and the non-backbone area is good. The disadvantage is that no further regional configuration and synchronization are performed on the interconnected ports of the backbone area and the non-backbone area, resulting in repeated configuration, which affects the stability and efficiency of AS automatic domain division. Summary of the invention

[0004] The present invention provides an automatic domain division method based on the OSPF protocol, which solves the problems of "insufficient stability and low efficiency" existing in the prior art.

[0005] The present invention solves the technical problem through the following technical solutions:

[0006] An automatic domain division method based on OSPF protocol includes the following steps:

[0007] (1) Divide the external autonomous area into a backbone area and at least one non-backbone area;

[0008] (2) In the backbone area, all interconnected ports of routers in each backbone area and all interconnected ports of backbone area border routers are assigned a zero-valued OSPF area number;

[0009] A non-backbone area corresponds to a non-zero OSPF area number, and each non-zero OSPF area number is unique;

[0010] In each non-backbone area, for each non-backbone area border router, the interconnection port of the non-backbone area border router connected to any backbone area border router is assigned a zero-valued OSPF area number, and the remaining interconnection ports of the non-backbone area border router connected to the routers in the non-backbone area are assigned a non-zero-valued OSPF area number corresponding to the non-backbone area;

[0011] In each non-backbone area, for each router in the non-backbone area, each interconnection port connected to the non-backbone area border router and to routers in other non-backbone areas is configured with a non-zero OSPF area number corresponding to the non-backbone area;

[0012] (3) Allocate an IP address and mask to each interconnected port of all routers in the backbone area and each non-backbone area so that all interconnected ports are in the same network segment;

[0013] announcing all interconnected port network segments within the backbone area to the zero-value OSPF area of ​​the external autonomous area;

[0014] For each non-backbone area, all interconnected port segments of the non-backbone area are announced into a non-zero value OSPF area corresponding to the non-backbone area.

[0015] Furthermore, in step (1), the backbone area includes at least one backbone intra-area router and at least one backbone intra-area border router; the intra-area routers, the intra-area border routers, and the intra-area routers and the intra-area border routers are interconnected as needed;

[0016] In each non-backbone area, the non-backbone area includes at least one non-backbone area border router and at least one non-backbone intra-area router; the non-backbone area border routers, the non-backbone intra-area routers, and the non-backbone area border routers and the non-backbone intra-area routers are interconnected as needed;

[0017] For each backbone area border router, the backbone area border router is interconnected with non-backbone area border routers in each non-backbone area as needed.

[0018] Furthermore, in step (2), in each non-backbone area, for each non-backbone area border router, the non-backbone area router connected to the non-backbone area border router obtains the non-zero OSPF area number of the interconnection port connected to the non-backbone area border router through LLDP.

[0019] Further, in step (2), in each non-backbone area, for each non-backbone area border router, the non-backbone area router connected to the non-backbone area border router obtains the non-zero value OSPF area number of the interconnection port connected to the non-backbone area border router through the TLV field in LLDP.

[0020] The advantages and effects of the present invention are:

[0021] All interconnected ports of routers in the backbone area are assigned a zero-valued OSPF area number. One non-backbone area corresponds to one non-zero-valued OSPF area number, and each non-zero-valued OSPF area number is different. For each non-backbone area border router, the interconnected port connected to the backbone area border router is assigned a zero-valued OSPF area number, and the interconnected port connected to the router in the non-backbone area is assigned a non-zero-valued OSPF area number. All interconnected ports of routers in all non-backbone areas are assigned a non-zero-valued OSPF area number. After all interconnected ports are assigned OSPF area numbers, all interconnected ports are set in the same network segment and announced to their respective OSPF areas to avoid repeated configurations and improve the stability and efficiency of automatic domain division. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the network topology diagram after AS division and interconnection port configuration.

[0023] Figure 2 A network topology diagram according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to examples, but the present invention is not limited to these examples.

[0025] An automatic domain division method based on OSPF protocol includes the following steps:

[0026] (1) Divide the external autonomous area into a backbone area and at least one non-backbone area;

[0027] (2) In the backbone area, all interconnected ports of routers in each backbone area and all interconnected ports of backbone area border routers are assigned a zero-valued OSPF area number;

[0028] A non-backbone area corresponds to a non-zero OSPF area number, and each non-zero OSPF area number is unique;

[0029] In each non-backbone area, for each non-backbone area border router, the interconnection port of the non-backbone area border router connected to any backbone area border router is assigned a zero-valued OSPF area number, and the remaining interconnection ports of the non-backbone area border router connected to the routers in the non-backbone area are assigned a non-zero-valued OSPF area number corresponding to the non-backbone area;

[0030] In each non-backbone area, for each router in the non-backbone area, each interconnection port connected to the non-backbone area border router and to routers in other non-backbone areas is configured with a non-zero OSPF area number corresponding to the non-backbone area;

[0031] (3) Allocate an IP address and mask to each interconnected port of all routers in the backbone area and each non-backbone area so that all interconnected ports are in the same network segment;

[0032] announcing all interconnected port network segments within the backbone area to the zero-value OSPF area of ​​the external autonomous area;

[0033] For each non-backbone area, all interconnected port segments of the non-backbone area are announced into a non-zero value OSPF area corresponding to the non-backbone area.

[0034] Furthermore, in step (1), the backbone area includes at least one backbone intra-area router and m (m≥1) backbone intra-area border routers; the intra-area routers in each backbone area, the intra-area border routers in each backbone area, and the intra-area routers and the intra-area border routers in each backbone area are interconnected as needed;

[0035] In each non-backbone area, the non-backbone area includes at least one non-backbone area border router and at least one non-backbone intra-area router; the non-backbone area border routers, the non-backbone intra-area routers, and the non-backbone area border routers and the non-backbone intra-area routers are interconnected as needed;

[0036] For each backbone area border router, the backbone area border router is interconnected with non-backbone area border routers in each non-backbone area as needed.

[0037] Furthermore, the method for dividing the backbone area and the non-backbone area is a prior art. In step (1), the AS is divided into a backbone area and n (n≥1) non-backbone areas. The backbone area is the backbone of the network and is the switching center connecting other areas; the non-backbone area refers to the area connected to the backbone area. If routing information needs to be exchanged with other areas, it needs to be forwarded through the backbone area. The routers in the backbone area are interconnected on demand, and the routers in the non-backbone areas are interconnected on demand. The backbone area and the non-backbone areas are interconnected on demand through border routers. The network topology diagram after the AS completes the division of the backbone area and the non-backbone area, completes the area number configuration of the interconnection port, and completes the network segment declaration is shown in the figure. Figure 1 shown.

[0038] The embodiment of the present invention further describes the technical solution by taking one backbone area and two non-backbone area ASs. Figure 2 This is a network topology diagram after the backbone area and non-backbone area division, the area number configuration of the interconnected ports, and the network segment declaration are completed for this embodiment. Figure 2 In the figure, AS is divided into one backbone area and two non-backbone areas, the two non-backbone areas are the first backbone area and the second backbone area. The backbone area includes routers R0 and R1, R0 is a router in the backbone area, R1 is a border router in the backbone area, and R0 and R1 are interconnected; the first non-backbone area includes routers R2, R4, and R5, R2 is a border router in the first non-backbone area, R4 is one of the routers in the first non-backbone area, R5 is another router in the first non-backbone area, R2 is interconnected with R1, and R2 is also interconnected with R4 and R5; the second non-backbone area includes routers R3, R6, and R7, R3 is a border router in the second non-backbone area, R6 is one of the routers in the second non-backbone area, R7 is another router in the second non-backbone area, R3 is interconnected with R1, R6 is interconnected with R3 and R7, and R7 is interconnected with R6.

[0039] right Figure 2After completing the area division of the network topology structure: for the backbone area, all interconnected ports on R0 and R1 are assigned a zero OSPF area number (Area 0); for the border router R2 in the first non-backbone area, the port on R2 that is interconnected with R1 is assigned a zero OSPF area number (Area 0), the port on R2 that is interconnected with R4 and R5 is assigned a non-zero OSPF area number (Area1), and the ports on R4 and R5 that are interconnected with other routers are all assigned a non-zero OSPF area number (Area1); for the border router R3 in the second non-backbone area, the port on R3 that is interconnected with R1 is assigned a zero OSPF area number (Area 0), the port on R3 that is interconnected with R6 is assigned a non-zero OSPF area number (Area 2), and all interconnected ports on R6 and R7 that are connected to other routers are assigned a non-zero OSPF area number (Area 2). For the nth (n≥1) non-backbone area, its non-zero OSPF area number is usually set to Area n.

[0040] Allocate IP and mask to each interconnected port of all routers in the backbone area and non-backbone areas so that all interconnected ports are in the same network segment and are announced in their respective OSPF areas: the port on R0 that interconnects with R1 is configured as 34.0.0.1 / 23Area 0, the port on R1 that interconnects with R0 is configured as 34.0.0.2 / 23Area0, the port on R1 that interconnects with R2 is configured as 34.0.2.1 / 23Area 0, the port on R1 that interconnects with R3 is configured as 34.0.16.1 / 23Area 0; the port on R2 that interconnects with R1 is configured as 34.0.2.2 / 23Area0, the port on R2 that interconnects with R4 is configured as 34.0.4.1 / 23Area 1, the port on R2 that is interconnected with R5 is configured as 34.0.8.1 / 23Area1, the port on R4 that is interconnected with R2 is configured as 34.0.4.2 / 23Area 1, the port on R5 that is interconnected with R2 is configured as 34.0.8.2 / 23Area 1, the port on R3 that is interconnected with R1 is configured as 34.0.16.2 / 23Area0, the port on R3 that is interconnected with R6 is configured as 34.0.32.1 / 23Area 2, the port on R6 that is interconnected with R3 is configured as 34.0.32.2 / 23Area 2, the port on R6 that is interconnected with R7 is configured as 34.0.64.1 / 23Area 2, and the port on R7 that is interconnected with R6 is configured as 34.0.64.2 / 23Area 2. Declaring each configured interconnected port to its respective area can avoid duplicate configuration and improve the stability and efficiency of automatic zoning.

[0041] Furthermore, in step (2), in each non-backbone area, for each non-backbone area border router, the non-backbone area router connected to the non-backbone area border router obtains the non-zero OSPF area number of the interconnection port connected to the non-backbone area border router through LLDP. LLDP is a data link layer protocol that enables routers in access network areas to discover and advertise and exchange information with each other, and can be used to exchange configuration information between routers, and can dynamically discover the configuration information of the opposite router directly connected to the router.

[0042] Furthermore, in step (2), in each non-backbone area, for each non-backbone area border router, the router in the non-backbone area connected to the non-backbone area border router obtains the non-zero value OSPF area number of the interconnection port connected to the non-backbone area border router through the TLV field in LLDP. The LLDP message is provided with a TLV field, and the TLV field carries the OSPF area number of the opposite router. The router performs its own area configuration according to the role identity of the backbone area router, the backbone area border router, the non-backbone area router and the non-backbone area border router and the OSPF area number provided by the TLV field of the opposite router.

[0043] Figure 2 In the example, R4 obtains the area configuration information of the directly connected R2 port through LLDP, that is, the non-zero OSPF area number (Area 1), R5 obtains the area configuration information Area 1 of the directly connected R2 port through LLDP, R6 obtains the area configuration information Area 2 of the directly connected R3 port through LLDP, and R7 obtains the area configuration information Area 2 of the directly connected R6 port through LLDP.

Claims

1. An automatic domain division method based on OSPF protocol, characterized in that: The steps include: (1) Divide the external autonomous area into a backbone area and at least one non-backbone area; (2) In the backbone area, all interconnected ports of routers in each backbone area and all interconnected ports of backbone area border routers are assigned a zero-valued OSPF area number; A non-backbone area corresponds to a non-zero OSPF area number, and each non-zero OSPF area number is unique; In each non-backbone area, for each non-backbone area border router, the interconnection port of the non-backbone area border router connected to any backbone area border router is assigned a zero-valued OSPF area number, and the remaining interconnection ports of the non-backbone area border router connected to the routers in the non-backbone area are assigned a non-zero-valued OSPF area number corresponding to the non-backbone area; In each non-backbone area, for each router in the non-backbone area, each interconnection port connected to the non-backbone area border router and to routers in other non-backbone areas is configured with a non-zero OSPF area number corresponding to the non-backbone area; (3) Allocate an IP address and mask to each interconnected port of all routers in the backbone area and each non-backbone area so that all interconnected ports are in the same network segment; announcing all interconnected port network segments within the backbone area to the zero-value OSPF area of ​​the external autonomous area; For each non-backbone area, all interconnected port segments of the non-backbone area are announced into a non-zero value OSPF area corresponding to the non-backbone area.

2. The automatic domain division method based on the OSPF protocol according to claim 1 is characterized in that: In step (1), the backbone area includes at least one backbone intra-area router and at least one backbone intra-area border router; the routers in each backbone area, the backbone intra-area border routers, and the backbone intra-area routers and the backbone intra-area border routers are interconnected as needed; In each non-backbone area, the non-backbone area includes at least one non-backbone area border router and at least one non-backbone intra-area router; the non-backbone area border routers, the non-backbone intra-area routers, and the non-backbone area border routers and the non-backbone intra-area routers are interconnected as needed; For each backbone area border router, the backbone area border router is interconnected with non-backbone area border routers in each non-backbone area as needed.

3. The automatic domain division method based on the OSPF protocol according to claim 2 is characterized in that: In step (2), in each non-backbone area, for each non-backbone area border router, the non-backbone area router connected to the non-backbone area border router obtains the non-zero OSPF area number of the interconnection port connected to the non-backbone area border router through LLDP.

4. The automatic domain division method based on the OSPF protocol according to claim 2 is characterized in that: In step (2), in each non-backbone area, for each non-backbone area border router, the non-backbone area router connected to the non-backbone area border router obtains the non-zero value OSPF area number of the interconnection port connected to the non-backbone area border router through the TLV field in LLDP.

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