Method and device for maintaining routes

• US 8,065,434 B2
• Filed: 12/30/2010
• Issued: 11/22/2011
• 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
• Primary Examiner(s): Nguyen; Minh-Chau
• Application Number:
  US12/982,733
• Publication Number:
  US 20110085554A1
• Time in Patent Office: 327 Days
• Field of Search: None
• US Class Current: 709/244
• 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;

acquiring, by each PoP node, routing information of a detailed prefix covered by a super prefix issued by the PoP node itself from an edge network of the PoP node, 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, and wherein 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 the connected edge network with a proximate PoP node that issues the routing information of the super prefix covering the detailed prefix; and

synchronizing, by each PoP node, the acquired routing information of the detailed prefix with the other PoP nodes within the same PoP group to make each PoP node to get routing information of all detailed prefixes covered by the super prefix.

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 routing information of the detailed prefix comprises the detailed prefix and a routable address, priority, and overhead information of the border router.

4. The method according to claim 1, 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.

5. The method according to claim 1 further comprising:

when the routing information of the detailed prefix within the edge network connected to a border router changes, performing registration update, by the border router, to a 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.

6. 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.

7. 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).

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

a route maintenance module that stores routing information of a super prefix;

an issue module that issues routing information of a super prefix stored in the route maintenance module, wherein the routing information of a same super prefix is issued within the same PoP group, and the routing information of different super prefixes is issued within different PoP groups;

a receiver implemented in hardware that receives routing information of a detailed prefix covered by a super prefix issued by the PoP node itself from an edge network of the PoP node, and stores the received routing information of the detailed prefix in the route maintenance module; and

a synchronization module that synchronizes the routing information of the detailed prefix stored in the route maintenance module with other PoP nodes within the same PoP group to make each PoP node to get routing information of all detailed prefixes covered by the super prefix,

wherein the received 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, and

wherein 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 the connected edge network with a proximate PoP node that issues the routing information of the super prefix covering the detailed prefix.