CN111245716A - Inter-domain routing method, device and system - Google Patents

Abstract

The disclosure provides an inter-domain routing method, device and system, and relates to the field of communication. According to the method, the integrated controller is arranged in the autonomous system, the centralized controllers of different autonomous systems exchange the intra-network routes with each other, the integrated controller makes decisions on the inter-domain routes, and the forwarding information table of the inter-domain routes is issued to the intra-network routers of the autonomous systems, so that the intra-network routers of the autonomous systems do not need to operate eBGP and iBGP, only IGP is needed to operate, and network configuration is greatly simplified.

Description

Inter-domain routing method, device and system

Technical Field

The present disclosure relates to the field of communications, and in particular, to a method, device, and system for inter-domain routing.

Background

An Autonomous System (AS), also known AS an Autonomous domain, refers to a set of routers in a network that use the same routing protocol or follow the same routing management policy.

In order to maintain the reachability of IP (Internet Protocol, Protocol for interconnection between networks) between different ASs, ASBR (Autonomous System border Router) needs to run eBGP (external border Gateway Protocol), and the intra-net routers of the same AS need to run IGP (Internal Gateway Protocol) and also need to implement iBGP (Internal border Gateway Protocol).

Referring to a routing protocol configuration diagram of the autonomous system shown in fig. 1, inter-AS interconnection and interworking between ASBRs are realized through eBGP, and all routers in a domain realize iBGP full connection. The intra-network router needs to run IGP (not shown in the figure), and obtains the forwarding information table of the inter-domain route in an IGP and iBGP route iteration manner.

Disclosure of Invention

The inventor finds that the related art router needs to cooperate with IGP (Border Gateway Protocol) and BGP (Border Gateway Protocol) routing protocols to configure complex routing policies, so that the operation and maintenance of the network become complicated.

In view of this, the present disclosure provides an inter-domain routing scheme, where an integrated controller is set in an autonomous system, the integrated controllers of different autonomous systems exchange intra-network routes with each other, and the integrated controller makes a decision on the inter-domain routes and issues a forwarding information table of the inter-domain routes to an intra-network router of the autonomous system, so that the intra-network router of the autonomous system does not need to run eBGP and iBGP, but only needs to run IGP, thereby greatly simplifying network configuration.

Some embodiments of the present disclosure provide an inter-domain routing method, including:

each centralized controller collects the network routing of the autonomous system;

each centralized controller informs other centralized controllers of the intra-network route of the autonomous system;

each centralized controller determines inter-domain routes between the autonomous system and other autonomous systems according to the intra-network routes of the autonomous system announced by other centralized controllers;

and each centralized controller issues the inter-domain route between the autonomous system and other autonomous systems to the router of the autonomous system.

In some embodiments, when the centralized controller notifies other centralized controllers of the intra-network route of the autonomous system, the next hop information is specified; the centralized controller determines the inter-domain route between the autonomous system and other autonomous systems according to the intra-network route of the autonomous system announced by other centralized controllers and by combining the appointed next hop information.

In some embodiments, the centralized controller dynamically determines inter-domain routes between the autonomous system and other autonomous systems according to the intra-network routes of the autonomous systems notified by other centralized controllers, in combination with a preset policy.

In some embodiments, the preset policies include a load balancing policy, a shortest path policy, a minimum delay policy, and a designated path policy.

In some embodiments, each centralized controller advertises the intra-network routes of the autonomous system to other centralized controllers based on the border gateway protocol BGP.

In some embodiments, the interdomain routes between the present autonomous system and the other autonomous systems include destination IP address information at the other autonomous systems and an autonomous system border router ASBR as a next hop at the present autonomous system.

In some embodiments, the advertised in-network route of the autonomous system includes IP address information in the autonomous system, or the advertised in-network route of the autonomous system includes IP address information in the autonomous system and its corresponding autonomous system border router ASBR as a next hop.

In some embodiments, the centralized controller is a software defined network, SDN, centralized controller.

In some embodiments, an intra-network router within an autonomous system forwards outgoing traffic to a corresponding autonomous system border router of an inter-domain route according to an operating interior gateway protocol IGP; the autonomous system boundary router is configured with a default route, and an output interface of the autonomous system boundary router is an internetworking interface.

Some embodiments of the present disclosure propose a centralized controller for inter-domain routing, including:

a memory; and

a processor coupled to the memory, the processor configured to perform the interdomain routing method of any of the preceding embodiments based on instructions stored in the memory.

Some embodiments of the present disclosure provide an inter-domain routing system, including a plurality of autonomous systems, each autonomous system including:

the foregoing centralized controller;

several autonomous system boundary routers configured with default route, and their output interfaces are internetwork interconnection interfaces;

and the plurality of in-network routers are configured to forward the outflow to corresponding autonomous system boundary routers of the inter-domain router according to the running Interior Gateway Protocol (IGP).

Some embodiments of the present disclosure propose a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, implements the interdomain routing method of any one of the preceding embodiments.

Drawings

The drawings that will be used in the description of the embodiments or the related art will be briefly described below. The present disclosure will be more clearly understood from the following detailed description, which proceeds with reference to the accompanying drawings,

it is to be understood that the drawings in the following description are merely exemplary of the disclosure, and that other drawings may be derived from those drawings by one of ordinary skill in the art without undue inventive faculty.

Fig. 1 shows a routing protocol configuration diagram of a related art autonomous system.

Fig. 2 illustrates a schematic diagram of an interdomain routing system of some embodiments of the present disclosure.

Fig. 3 illustrates a schematic diagram of an interdomain routing method of some embodiments of the present disclosure.

Fig. 4 shows a schematic diagram of a centralized controller for interdomain routing of some embodiments of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure.

Fig. 2 illustrates a schematic diagram of an interdomain routing system of some embodiments of the present disclosure.

As shown in FIG. 2, the interdomain routing system of this embodiment comprises several autonomous systems, such AS AS1 and AS2, shown in the figure. A centralized controller is deployed at each autonomous system. The centralized controller is, for example, an SDN (Software defined network) centralized controller. Each autonomous system also includes several autonomous system border routers, such asASBRs 1, ASBRs 2, ASBRs 3, ASBRs 4 as shown in the figure. Each autonomous system also includes a number of in-network routers, shown as R1, R2, R3, R4.

Fig. 3 illustrates a schematic diagram of an interdomain routing method of some embodiments of the present disclosure.

As shown in fig. 3, the inter-domain routing method according to this embodiment includes:

in step S310, each centralized controller collects the intra-network routes of the own autonomous system.

For example, referring to fig. 2, the intra-network routes of the local autonomous system AS1 collected by the centralizedcontroller 1 are 1.0.0.0/8, 2.0.0.0/8, 3.0.0.0/8, 4.0.0.0/8, and the intra-network routes of the local autonomous system AS2 collected by the centralized controller 2 are 5.0.0.0/8, 6.0.0.0/8, 7.0.0.0/8, 8.0.0.0/8.

In step S320, each centralized controller notifies the other centralized controllers of the intra-network route of the own autonomous system.

The network route of the autonomous system notified by the centralized controller may include, for example, IP address information in the autonomous system, and optionally, next hop information specified for the IP address information in the autonomous system, for example, information of an ASBR specified as a next hop. It should be noted that the ASBR designated as the next hop by the centralized controller is also located in the present autonomous system.

For example, referring to fig. 2, the intra-network routes of the local autonomous system AS1 advertised by thecentralized controller 1 to the centralized controller 2 are, for example, 1.0.0.0/8, 2.0.0/8, 3.0.0.0/8, 4.0.0.0/8, and the next hops of 1.0.0.0/8 and 2.0.0.0/8 may be further designated AS ASBRs 1, 3.0.0.0/8 and 4.0.0.0/8 AS ASBRs 2.

For another example, referring to fig. 2, the intra-network routes of the autonomous system AS2 advertised by the centralized controller 2 to the centralizedcontroller 1 are, for example, 5.0.0.0/8, 6.0.0.0/8, 7.0.0.0/8, 8.0.0.0/8, and the next hops of 5.0.0.0/8 and 6.0.0.0/8 may be further designated AS ASBRs 3, the next hops of 7.0.0.0/8 and 8.0.0.0/8 are further designated AS ASBRs 4.

In some embodiments, the centralized controller may advertise the intra-network routes of the autonomous system to other centralized controllers, e.g., based on the BGP protocol.

In step S330, each centralized controller determines the inter-domain route between the autonomous system and another autonomous system according to the intra-network route of its autonomous system notified by another centralized controller.

The inter-domain routing determined by the centralized controller between the autonomous system and other autonomous systems comprises the following steps: and the destination IP address information of other autonomous systems and the corresponding information of the ASBR which is positioned in the autonomous system and is used as the next hop.

In some embodiments, if the centralized controller specifies next hop information when notifying the other centralized controller of the intra-network route of the autonomous system, the centralized controller determines the inter-domain route between the autonomous system and the other autonomous systems according to the intra-network route of the autonomous system notified by the other centralized controller, in combination with the specified next hop information.

For example, the intra-network routes of the present autonomous system AS1 advertised by thecentralized controller 1 to the centralized controller 2 are, for example, 1.0.0.0/8, 2.0.0.0/8, 3.0.0/8, 4.0.0.0/8, and the next hops of 1.0.0.0/8 and 2.0.0.0/8 are designated ASASBRs 1, and the next hops of 3.0.0.0/8 and 4.0.0.0/8 are designated AS ASBRs 2. Then, the interdomain route between AS2 and AS1 determined by the centralized controller 2 is: the next hops for destination addresses 1.0.0.0/8 and 2.0.0/8 are ASBR3 (assuming the internetworking interface of ASBR1 corresponds to ASBR3) and the next hops for destination addresses 3.0.0.0/8 and 4.0.0.0/8 are ASBR4 (assuming the internetworking interface of ASBR2 corresponds to ASBR 4).

As another example, the intra-network routes of the autonomous system AS2 advertised by the centralized controller 2 to thecentralized controller 1 are, for example, 5.0.0.0/8, 6.0.0.0/8, 7.0.0.0/8, 8.0.0.0/8, and the next hops of 5.0.0.0/8 and 6.0.0.0/8 are designated AS ASBRs 3, and the next hops of 7.0.0.0/8 and 8.0.0.0/8 are designated AS ASBRs 4. Then, the interdomain route between AS1 and AS2 determined by thecentralized controller 1 is: the next hop for destination addresses 5.0.0.0/8, 6.0.0.0/8 is ASBR1 (assuming the INTERNET INTERCONNECT of ASBR3 corresponds to ASBR1), and the next hop for destination addresses 7.0.0.0/8 and 8.0.0.0/8 is ASBR2 (assuming the INTERNET INTERCONNECT of ASBR4 corresponds to ASBR 2).

In some embodiments, if the centralized controller does not advertise the next hop information, the centralized controller dynamically determines inter-domain routes between the autonomous system and other autonomous systems according to the intra-network routes of its autonomous system advertised by other centralized controllers based on the full-network topology view and in combination with a preset policy, that is, specifies an egress router for the outgoing flows of different destination IP addresses according to the preset policy. The preset policies include, for example, a load balancing policy, a shortest path policy, a minimum latency policy, a specified path policy, etc., but are not limited to the illustrated examples.

The following describes a process of dynamically determining inter-domain routing by taking a load balancing policy as an example.

In order to realize load balance of internetwork flow among a plurality of ASBRs, the centralized controller dynamically determines routing information according to the inter-domain routes obtained by exchange and based on a whole-network topological view and according to the monitored flow carried by each summary inter-domain route, the next hop is the ASBR, and the routing information can be dynamically issued to a whole-network router (except the ASBR). Referring to fig. 2, anintegrated controller 1 of an AS1 monitors that traffic carried by 2 summarized routes 5.0.0.0 to 6.0.0.0 advertised by an AS2 is assumed to be 10Gb/s, and simultaneously monitors that traffic carried by 2 summarized routes 7.0.0.0 to 8.0.0.0 advertised by an AS2 is assumed to be 20 Gb/s. Thecentralized controller 1 of the AS1 also monitors that the utilization rate of the internetwork interconnection link bandwidth between the ASBR1 and the ASBR3 is high, the remaining bandwidth can only carry 10Gb/s of traffic, and simultaneously monitors that the utilization rate of the internetwork interconnection link bandwidth between the ASBR2 and the ASBR4 is low, and the remaining bandwidth can carry 20Gb/s of traffic. In this case, thecentralized controller 1 of the AS1 preferably uses ASBR1 AS an egress of IP traffic having a destination address in the range of 5.0.0.0 to 6.0.0.0, and simultaneously advertises the interdomain routes 5.0.0.0 to 6.0.0.0 to routers (such AS R1 and R2 in the figure) other than ASBRs in the entire network, and designates the next hop to ASBR1 for routes 5.0.0.0 to 6.0.0.0. Similarly, thecentralized controller 1 of the AS1 preferably selects ASBR2 AS the egress of IP traffic with destination addresses in the range of 7.0.0.0-8.0.0.0, and simultaneously announces the interdomain routes 7.0.0.0-8.0.0.0 to routers (such AS R1 and R2 in the figure) except the ASBR in the whole network, and designates the next hop AS ASBR2 for the routes 7.0.0.0-8.0.0.0.

In step S340, each centralized controller issues an interdomain route between the autonomous system and another autonomous system to the router of the autonomous system.

For example, referring to the previous example, thecentralized controller 1 of AS1 advertises interdomain routes 5.0.0.0-6.0.0.0 to routers (such AS R1 and R2 in the figure) of the entire network except for ASBRs, and assigns the next hop to ASBR1 for 5.0.0.0-6.0.0.0 routes; and the interdomain routes 7.0.0.0-8.0.0.0 are announced to routers (such as R1 and R2 in the figure) except the ASBR in the whole network, and the next hop is designated as ASBR2 for the routes 7.0.0.0-8.0.0.0.

In step S350, the intra-network router in the autonomous system forwards the outgoing traffic to the border router of the autonomous system corresponding to the inter-domain router according to the running IGP protocol.

For example, the intra-network routers R1 and R2 within the AS1 forward outbound traffic with destination addresses of 5.0.0.0-6.0.0.0 to the ASBR1 corresponding to the interdomain route, and forward outbound traffic with destination addresses of 7.0.0.0-8.0.0.0 to the ASBR2 corresponding to the interdomain route.

In step S360, the border router of the autonomous system configures a default route, an egress interface of the border router is an internetworking interface, and an egress traffic is forwarded to the internetworking link according to the default route.

For example, ASBR1 forwards outgoing traffic to ASBR3 according to a default route, and ASBR2 forwards outgoing traffic to ASBR4 according to a default route.

In the embodiment, the integrated controller is arranged in the autonomous system, the integrated controllers of different autonomous systems exchange the intra-network routes with each other, the integrated controller makes a decision on the inter-domain routes, and a forwarding information table of the inter-domain routes is issued to the intra-network routers of the autonomous systems, so that the intra-network routers of the autonomous systems do not need to run eBGP and iBGP, only IGP is needed to run, and network configuration is greatly simplified. In addition, according to the strategy for dynamically determining the selection of the inter-domain routing, such as a load balancing strategy, a shortest path strategy, a minimum delay strategy, a specified path strategy and the like, the traffic engineering of the whole network and the load balancing of multiple exits among networks can be realized.

Fig. 4 shows a schematic diagram of a centralized controller for interdomain routing of some embodiments of the present disclosure.

As shown in fig. 4, the centralized controller 400 of this embodiment includes:

a memory 410; and

a processor 420 coupled to the memory, the processor configured to execute the interdomain routing method of any of the preceding embodiments based on instructions stored in the memory.

Memory 410 may include, for example, system memory, fixed non-volatile storage media, and the like. The system memory stores, for example, an operating system, an application program, a Boot Loader (Boot Loader), and other programs.

Some embodiments of the present disclosure propose a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, implements the interdomain routing method of any one of the preceding embodiments.

As will be appreciated by one skilled in the art, embodiments of the present disclosure may be provided as a method, system, or computer program product. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable non-transitory storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only exemplary of the present disclosure and is not intended to limit the present disclosure, so that any modification, equivalent replacement, or improvement made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.

Claims (12)

1. An inter-domain routing method, comprising:

each centralized controller collects the network routing of the autonomous system;

each centralized controller informs other centralized controllers of the intra-network route of the autonomous system;

each centralized controller determines inter-domain routes between the autonomous system and other autonomous systems according to the intra-network routes of the autonomous system announced by other centralized controllers;

and each centralized controller issues the inter-domain route between the autonomous system and other autonomous systems to the router of the autonomous system.

2. The method of claim 1, wherein,

when the centralized controller informs other centralized controllers of the intra-network routing of the autonomous system, the next hop information is appointed;

the centralized controller determines the inter-domain route between the autonomous system and other autonomous systems according to the intra-network route of the autonomous system announced by other centralized controllers and by combining the appointed next hop information.

3. The method of claim 1, wherein,

the centralized controller dynamically determines inter-domain routes between the autonomous system and other autonomous systems according to the intra-network routes of the autonomous systems notified by other centralized controllers and by combining preset strategies.

4. The method of claim 3, wherein,

the preset strategies comprise a load balancing strategy, a shortest path strategy, a minimum time delay strategy and a specified path strategy.

5. The method of claim 1, wherein,

and each centralized controller informs the other centralized controllers of the intra-network route of the autonomous system based on a Border Gateway Protocol (BGP).

6. The method of claim 1, wherein,

the interdomain routing between the autonomous system and other autonomous systems includes destination IP address information of other autonomous systems and autonomous system border router ASBR as next hop in the autonomous system.

7. The method of claim 1, wherein,

the advertised intra-network routes of the local autonomous system include IP address information within the local autonomous system, or,

the announced in-network routing of the autonomous system comprises IP address information in the autonomous system and an Autonomous System Boundary Router (ASBR) corresponding to the IP address information as a next hop.

8. The method of claim 1, wherein,

the centralized controller is a Software Defined Network (SDN) centralized controller.

9. The method of claim 1, wherein,

the intra-network router in the autonomous system forwards the outflow flow to a boundary router of the autonomous system corresponding to the inter-domain router according to an Internal Gateway Protocol (IGP) in operation;

the autonomous system boundary router is configured with a default route, and an output interface of the autonomous system boundary router is an internetworking interface.

10. A centralized controller for interdomain routing, comprising:

a memory; and

a processor coupled to the memory, the processor configured to perform the interdomain routing method of any of claims 1-8 based on instructions stored in the memory.

11. An inter-domain routing system comprising a plurality of autonomous systems, each autonomous system comprising:

the centralized controller of claim 10;

several autonomous system boundary routers configured with default route, and their output interfaces are internetwork interconnection interfaces;

and the plurality of in-network routers are configured to forward the outflow to corresponding autonomous system boundary routers of the inter-domain router according to the running Interior Gateway Protocol (IGP).

12. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, implements the inter-domain routing method of any one of claims 1-8.

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