An automatic sub-domain method based on OSPF protocol

Abstract

The application provides an automatic domain division method based on an OSPF protocol, which divides an AS into areas to obtain a backbone area and a non-backbone area, all interconnection ports of routers in the backbone area are allocated zero value OSPF area numbers, one non-backbone area corresponds to one non-zero value OSPF area number, each non-zero value OSPF area number is different, for each non-backbone area boundary router, an interconnection port connected with a backbone area boundary router is allocated a zero value OSPF area number, an interconnection port connected with a non-backbone area router is allocated a non-zero value OSPF area number, all interconnection ports of non-backbone area routers are allocated non-zero value OSPF area numbers, after all interconnection ports are allocated with OSPF area numbers, all interconnection ports are set in the same network segment, and are declared to the respective OSPF areas, so that the situation of repeated configuration can be avoided, and the stability and efficiency of automatic domain division are improved.

Description

Technical Field

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

[0002] An autonomous system (AS) is a group of network elements that exchange routing information using a unified routing protocol. OSPF is a typical link-state routing protocol that collects link-state information from the network to construct a topology for the entire AS. Based on this topology, it calculates the shortest path tree to determine the optimal route to each destination.

[0003] In the prior art, the OSPF routing autonomous domain partitioning 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: obtaining the network topology and using the OSPF convergence model to predict the size of the network's balanced partition; using the size of the balanced partition as a partition constraint, and based on the node centrality and link bandwidth, selecting the backbone nodes in the network, and setting the area_id field of the backbone node to 0 to obtain the backbone area; using a community detection algorithm based on graph data to divide the network outside the backbone area into several non-backbone areas, the size of the non-backbone area is equal to the size of the balanced partition; optimizing the non-backbone area until there is no disconnected area between the backbone area and the non-backbone area, and outputting the non-backbone area; selecting nodes in the backbone area that meet preset conditions as boundary nodes, and updating the node_type field of the boundary node to ABR to obtain the final OSPF routing autonomous domain partitioning scheme. The advantages of this method are low inter-area traffic and good connectivity between backbone and non-backbone areas. However, the disadvantage is that no further regional configuration and synchronization are performed on the interconnected ports of the backbone and non-backbone areas, resulting in duplicate configurations and affecting 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" 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 the 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) All interconnected ports of routers in each backbone area and of each backbone area border router in the backbone area 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 connecting the non-backbone area border router and any backbone area border router is assigned a zero-valued OSPF area number, and the interconnection port connecting the non-backbone area border router and a router in the non-backbone area is 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) Assign IP addresses and masks to each interconnected port of all routers in the backbone area and non-backbone areas so that all interconnected ports are on the same network segment;

[0013] Advertise all interconnected port 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 network 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 area router and at least one backbone area border router; the backbone area routers, the backbone area border routers, and the backbone area routers and the backbone 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 area router; the non-backbone area border routers, the non-backbone area routers, and the non-backbone area border routers and the non-backbone area routers are interconnected on demand;

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

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

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

[0021] All interconnection ports of the backbone area internal router are assigned zero value OSPF area numbers, one non-backbone area corresponds to one non-zero value OSPF area number, and each non-zero value OSPF area number is different, for each non-backbone area border router, the interconnection port connected with the backbone area border router is assigned a zero value OSPF area number, and the interconnection port connected with the non-backbone area internal router is assigned a non-zero value OSPF area number, all interconnection ports of the non-backbone area internal router are assigned non-zero value OSPF area numbers, and after assigning OSPF area numbers to all interconnection ports, all interconnection ports are set in the same network segment and announced to the respective OSPF area, avoiding the situation of repeated configuration, and improving the stability and efficiency of automatic domain division. BRIEF DESCRIPTION OF DRAWINGS

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

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

[0024] The present application is further described below in conjunction with embodiments, but the present application is not limited to these embodiments.

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

[0026] (1) dividing an external autonomous area into one backbone area and at least one non-backbone area;

[0027] (2) in the backbone area, all interconnection ports of each backbone area internal router and each backbone area border router are assigned zero value OSPF area numbers;

[0028] One non-backbone area corresponds to one 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 with any backbone area border router is allocated a zero OSPF area number, and the interconnection port of the non-backbone area border router connected with a non-backbone area internal router is allocated a non-zero OSPF area number corresponding to the non-backbone area;

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

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

[0032] All interconnection port network segments in the backbone area are announced into the zero OSPF area of the external autonomous area;

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

[0034] Further, in step (1), in the backbone area, at least one backbone area internal router and m (m≥1) backbone area border routers are included; the backbone area internal routers, the backbone area border routers, and the backbone area internal routers and the backbone area border routers 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 area internal router; the non-backbone area border routers, the non-backbone area internal routers, and the non-backbone area border routers and the non-backbone area internal routers are interconnected as needed;

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

[0037] Further, the method for dividing backbone area and non-backbone area is prior art. In step (1), the AS is divided into one backbone area and n (n≥1) non-backbone areas. The backbone area is the main network and is the switching center connecting other areas; the non-backbone area refers to the area connected to the backbone area, and if the area needs to interact with other areas, the backbone area needs to be forwarded. In the backbone area, each router is interconnected as needed, in each non-backbone area, each router is interconnected as needed, and the backbone area and each non-backbone area are interconnected through a boundary router as needed. The network topology graph after the AS completes the division of the backbone area and the non-backbone area, completes the area number configuration of the interconnected port, and completes the network segment declaration is shown in Figure 1 .

[0038] The embodiment of the application further describes the technical solution of the AS with one backbone area and two non-backbone areas. Figure 2 The network topology graph after the AS completes the division of the backbone area and the non-backbone area, completes the area number configuration of the interconnected port, and completes the network segment declaration. In Figure 2 , the AS is divided into one backbone area and two non-backbone areas, and the two non-backbone areas are respectively a first backbone area and a second backbone area. The backbone area includes routers R0 and R1, R0 is a backbone area router, R1 is a backbone area boundary router, and R0 is interconnected with R1; the first non-backbone area includes routers R2, R4, and R5, R2 is a first non-backbone area boundary router, R4 is one of the first non-backbone area routers, R5 is another of the first non-backbone area routers, 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 second non-backbone area boundary router, R6 is one of the second non-backbone area routers, R7 is another of the second non-backbone area routers, R3 is interconnected with R1, R6 is interconnected with R3 and R7, and R7 is interconnected with R6.

[0039] The network topology graph after the AS completes the division of the backbone area and the non-backbone area, completes the area number configuration of the interconnected port, and completes the network segment declaration. Figure 2After the network topology is divided into areas: For the backbone area, all interconnected ports on R0 and R1 are assigned a zero OSPF area number (Area 0). For border router R2 in the first non-backbone area, the port connecting to R1 is assigned a zero OSPF area number (Area 0), the ports connecting to R4 and R5 are assigned a non-zero OSPF area number (Area 1), and the ports connecting to other routers on R4 and R5 are all assigned a non-zero OSPF area number (Area 1). For border router R3 in the second non-backbone area, the port connecting to R1 is assigned a zero OSPF area number (Area 0), the port connecting to R6 is assigned a non-zero OSPF area number (Area 2), and all interconnected ports on R6 and R7 that connect to other routers are all 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 addresses and masks 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 connected to R5 is configured as 34.0.8.1 / 23Area1. The port on R4 connected to R2 is configured as 34.0.4.2 / 23Area 1. The port on R5 connected to R2 is configured as 34.0.8.2 / 23Area 1. The port on R3 connected to R1 is configured as 34.0.16.2 / 23Area0. The port on R3 connected to R6 is configured as 34.0.32.1 / 23Area 2. The port on R6 connected to R3 is configured as 34.0.32.2 / 23Area 2. The port on R6 connected to R7 is configured as 34.0.64.1 / 23Area 2. The port on R7 connected to R6 is configured as 34.0.64.2 / 23Area 2. Declaring each configured interconnected port to its respective zone 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, a non-backbone area router connected to the non-backbone area border router obtains a non-zero OSPF area number of an interconnection port connected to the non-backbone area border router via LLDP. LLDP is a data link layer protocol that enables routers in access network areas to discover, advertise, and exchange information with each other. It can be used to exchange configuration information between routers and can dynamically discover configuration information of a peer router directly connected to the router.

[0042] 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 the TLV field in the LLDP. The LLDP message is provided with a TLV field, and the TLV field carries the OSPF area number of the peer router. The router performs its own area configuration based on 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 peer router TLV field.

[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. 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) All interconnected ports of routers in each backbone area and of each backbone area border router in the backbone area 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 connecting the non-backbone area border router and any backbone area border router is assigned a zero-valued OSPF area number, and the interconnection port connecting the non-backbone area border router and a router in the non-backbone area is 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) Assign IP addresses and masks to each interconnected port of all routers in the backbone area and non-backbone areas so that all interconnected ports are on the same network segment; Advertise all interconnected port segments within the backbone area to the zero-value OSPF area of ​​the external autonomous area; For each non-backbone area, announce all interconnected port network segments of the non-backbone area into the non-zero value OSPF area corresponding to the non-backbone area; 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 the TLV field in LLDP.

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

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