Wide area network optimization proxy routing protocol

• US 8,064,362 B2
• Filed: 08/21/2008
• Issued: 11/22/2011
• Est. Priority Date: 08/21/2008
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Singh, Akshya Kumar, Datar, Vivek, Skriver, Jesper, Mekkattuparamban, Joji Thomas, Chen, Ming
• Primary Examiner(s): SEFCHECK, GREGORY B
• Application Number:
  US12/195,875
• Publication Number:
  US 20100046523A1
• Time in Patent Office: 1,188 Days
• Field of Search: None
• US Class Current: 370/254
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 67/141 Setup of application sessions admission control or resource allocation in data switching networks H04L47/70
• CPC Class Codes: H04L 67/563 Data redirection of data network streams

Abstract

In an example embodiment disclosed herein, Wide Area Network optimization modules coupled to peers are configured to maintain peer routing tables. The peer routing table (PRT) is used by the Wide Area Network optimization module to determine the peer for a given destination, such as an Internet Protocol “IP” destination. Each peer is responsible for advertising to other peers which networks the peer is able to reach. This information is advertised when a tunnel is first created and subsequently whenever necessary. Initially, a peer sends out a list of entries corresponding to its directly connected networks, with the exception of the network connected to the interface on which the peer is advertising (e.g. the network used for the tunnel). This enables other peers on the network to populate their PRT entries.

Claims

1. An apparatus, comprising:

a first interface coupled with a first associated network;

a second interface coupled with a second associated network;

optimization logic in communication with the first and second interfaces;

a memory configured to maintain data correlating networks with peer identifiers, the memory being coupled with the optimization logic;

wherein the optimization logic sends a first advertisement on a second interface, the first advertisement containing data representative of a network coupled with the first interface;

wherein the optimization logic receives on the first interface from a destination device having an address associated with the first associated network, a response packet for establishing a session with the destination device, wherein the source address of the packet is the address of the destination device;

wherein the optimization logic is configured to forward the response packet unchanged onto the second interface;

wherein the optimization logic is further configured to query a routing table stored in the memory for locating an entry in the routing table that matches the source address of the response packet responsive to receiving the response packet for establishing a session; and

wherein the optimization logic is configured to send a subsequent advertisement on the second interface, the routing table entry located corresponding to the source address of the response packet responsive to receiving the response packet for establishing a session and locating the entry in the routing table.

2. The apparatus set forth in claim 1, wherein the memory is configured to store a peer routing table.

3. The apparatus set forth in claim 1, wherein the memory is configured to store a routing table entry including data identifying a tunnel to a peer for a network associated with the source address of the response packet.

4. The apparatus set forth in claim 3, wherein the memory is configured to store the data identifying the tunnel as data identifying a Session Control Transport Protocol (SCTP) tunnel.

5. The apparatus set forth in claim 1, wherein the optimization logic is configured to forward a synchronization acknowledgement (SYN-ACK) packet.

6. The apparatus set forth in claim 1, wherein the second network interface is adapted to be coupled with a Wide Area Network (WAN).

7. The apparatus set forth in claim 6, wherein the optimization logic is further configured to advertise the routing table entry by sending a multicast packet onto the second network.

8. The apparatus set forth in claim 6, wherein the optimization logic advertises on the first interface a list of entries corresponding to directly connected networks associated with the second interface.

9. The apparatus set forth in claim 6, wherein the response packet establishes a tunnel between the network associated with the second interface and a device associated with the first network associated with the first interface.

10. A method, comprising:

sending on a second interface a first advertisement with data representative of a network coupled with the first interface responsive to creating a tunnel on the second interface;

receiving from a destination device having an address via a first interface a packet sent in response to a request to establish a session, the response packet having a source address for establishing a session with the destination device coupled with the network, wherein the source address of the response packet is the address of the destination device;

forwarding the response packet onto the second interface unchanged;

querying a routing table for locating an entry in the routing table that matches the source address of the response packet corresponding to the source address of the destination device disposed on the network coupled with the first interface responsive to receiving the response packet for establishing a session; and

sending a subsequent advertisement, on the second interface, the subsequent advertisement comprising data representative of the routing table entry for the network coupled with the first interface corresponding to the source address of the response packet, responsive to receiving the packet in response to a request for establishing a session and locating the entry in the routing table.

11. The method of claim 10, wherein the routing table is a peer routing table.

12. The method of claim 10, further comprising storing in the routing table an entry that comprises data identifying a tunnel to a peer for a network associated with the source address of the response packet.

13. The method of claim 10, wherein the data identifying the tunnel comprises data identifying a Session Control Transport Protocol (SCTP) tunnel.

14. The method of claim 10, wherein the response packet is a synchronization acknowledgement (SYN-ACK) packet.

15. The method set forth in claim 10, wherein the advertisement is sent via a multicast packet on the second network.

16. The method of claim 10, further comprising advertising on the first interface a list of entries corresponding to networks that are directly connected with the second interface.