Method and Device for Maintaining Routes

• US 20110085554A1
• Filed: 12/30/2010
• Published: 04/14/2011
• Est. Priority Date: 09/17/2007
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: XU, Xiaohu
• Granted Patent: US 8,065,434 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/021 Ensuring consistency of routing table updates, e.g. by using epoch numbers
• CPC Class Codes: H04L 45/033 by updating distance vector protocols
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing

Abstract

A method, system, and device for maintaining routes are provided. A communications network includes multiple point of presence (PoP) groups, where each of the PoP groups includes one or more PoP nodes. PoP nodes within the same PoP group issue routing information of the same super prefix. PoP nodes within different PoP groups issue routing information of different super prefixes. The method further includes the following steps. A PoP node acquires routing information of a detailed prefix covered by a super prefix issued by the PoP node and synchronizes the routing information of the detailed prefix with other PoP nodes within the same PoP group. The method, system, and device reduce flow of data forwarded by each PoP node.

Claims

1. A method for maintaining routes, applied in a communications network comprising multiple point of presence (PoP) groups, wherein each of the PoP groups comprises one or more PoP nodes, the method comprising:

issuing, by PoP nodes within the same PoP group, routing information of a same super prefix;

issuing, by PoP nodes within different PoP groups, routing information of different super prefixes; and

acquiring, by each PoP node, routing information of a detailed prefix covered by a super prefix issued by the PoP node itself, and synchronizing the routing information of the detailed prefix with the PoP nodes within the same PoP group.

2. The method according to claim 1, wherein the routing information of the super prefix issued by the PoP node is preset.

3. The method according to claim 1, wherein the acquired routing information of the detailed prefix covered by the super prefix is preset in the PoP node that issues the routing information of the super prefix or registered by a border router in the communications network dynamically.

4. The method according to claim 3, wherein the dynamically registering, by the border router in the communications network, the routing information of the detailed prefix covered by the super prefix comprises:

receiving, by the border router, the routing information of the super prefix issued by the PoP node, generating a routing table, recording an address of the PoP node that issues the routing information of the super prefix in the routing table, and registering, by the border router, the routing information of the detailed prefix within a connected edge network with a proximate PoP node that issues the routing information of the super prefix covering the detailed prefix.

5. The method according to claim 4, wherein the routing information of the detailed prefix comprises the detailed prefix and a routable address, priority, and overhead information of the border router.

6. The method according to claim 4, further comprising forwarding a data packet, wherein the method comprises:

hop-by-hop forwarding the data packet to the proximate PoP node that issues the routing information of the super prefix according to matching routing information of the super prefix, searching, by the proximate PoP node, a route optimally matching a destination IP address of the data packet in the routing table, determining an address of the border router corresponding to the optimal route, and sending the data packet to the border router in a tunnel mode.

7. The method according to claim 1 further comprising:

when the routing information of the detailed prefix within the edge network connected to the border router changes, performing registration update, by the border router, to the proximate PoP node that issues the routing information of the super prefix covering the detailed prefix; and

after the proximate PoP node receives the registration update, updating the routing information of the detailed prefix maintained by the proximate PoP node, and spreading the routing information update to other PoP nodes within the PoP group corresponding to the super prefix.

8. The method according to claim 4, further comprising:

when the routing information of the detailed prefix within the edge network connected to the border router changes, performing registration update, by the border router, to the proximate PoP node that issues the routing information of the super prefix covering the detailed prefix; and

after the proximate PoP node receives the registration update, updating the routing information of the detailed prefix maintained by the proximate PoP node, and spreading the routing information update to other PoP nodes within the PoP group corresponding to the super prefix.

9. The method according to claim 1, wherein the PoP nodes within the same PoP group synchronize routing information by using the Border Gateway Protocol (BGP).

10. A method for maintaining routes, comprising:

receiving routing information of a super prefix issued by a point of presence (PoP) node and generating a routing table, recording an address of the PoP node that issues the routing information of the super prefix in the routing table, and registering routing information of a detailed prefix within a connected edge network with a proximate PoP node that issues the routing information of the super prefix covering the detailed prefix.

11. The method according to claim 10, further comprising:

when the routing information of the detailed prefix within the connected edge network changes, performing registration update to the proximate PoP node that issues the routing information of the super prefix covering the detailed prefix.

12. A point of presence (PoP) node for maintaining routes, comprising:

a route maintenance module, configured to store routing information of a super prefix;

an issue module, configured to issue routing information of a super prefix stored in the route maintenance module;

a receiving module, configured to receive routing information of a detailed prefix covered by the super prefix issued by the issue module, and store the received routing information of the detailed prefix in the route maintenance module; and

a synchronization module, configured to synchronize the routing information of the detailed prefix stored in the route maintenance module with other PoP nodes within the same PoP group.