Methods and apparatus for data traffic offloading at a router

• US 8,787,303 B2
• Filed: 05/20/2011
• Issued: 07/22/2014
• Est. Priority Date: 10/05/2010
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Leung, Kent K., Iyer, Jayaraman, Andreasen, Flemming, Stammers, Timothy, Khouderchah, Michel
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): HAMPTON, TARELL A
• Application Number:
  US13/112,581
• Publication Number:
  US 20120082161A1
• Time in Patent Office: 1,159 Days
• Field of Search: 370/229, 370/230, 709/238, 709/239, 709/240
• US Class Current: 370/330
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/243 using M+N parallel active paths
• CPC Class Codes: H04L 45/26 Route discovery packet
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04W 28/0226 based on location or mobility handoff or reselection H04W36/00; mobile application services making use of the location of users or terminals H04W4/02
• CPC Class Codes: H04W 40/24 Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information

Abstract

This disclosure relates to a system and method for offloading selected data traffic in logical tunnels to the Internet. The offloading provides another data path for selected data traffic that can relieve the burden on a mobile operator'"'"'s network, such as the backhaul and core networks. As the proliferation of data rich content and increasingly more capable mobile devices has continued, the amount of data communicated over mobile operator'"'"'s networks has increased. Upgrading the existing network that was designed for voice calls is not desirable or practical for many mobile operators. This disclosure provides systems and methods for offloading data to the Internet at a router to relieve congestion on the mobile operator'"'"'s network.

Claims

1. A method comprising:

receiving, at an offloading element, a discovery message from a gateway;

in response to the discovery message, sending, to the gateway, an offload query message including an indication that the offloading element serves data packets selected by the gateway to be offloaded;

receiving an offloading instruction message from the gateway, wherein the offloading instruction message includes an identification of the selected packets to be offloaded at the offloading element to an Internet;

inspecting a first packet to determine that an identification of the first packet matches the identification of the selected packets in the offloading instruction message;

de-capsulating the first packet;

translating a network address in the de-capsulated first packet; and

offloading the de-capsulated and network-address-translated first packet to a server.

2. The method of claim 1, further comprising receiving data from the server over the Internet instead of over the gateway, encapsulating the data into a packetized form, translating a network address associated with the data, and transmitting the encapsulated data to a base station.

3. The method of claim 1, wherein the first packet travels over a tunnel established between a base station and an access gateway and the offloading element inspects the first packet by snooping into the tunnel.

4. The method of claim 1, further comprising inspecting a second packet to determine if the second packet includes the offloading instruction message.

5. The method of claim 1, wherein the identification of the selected packets in the offloading instruction message includes a tunnel endpoint identifier (TEID) of a tunnel associated with the selected packets.

6. The method of claim 1, further comprising:

determining at the gateway that a second packet, which is determined to be offloaded at the offloading element, be handed over to a new offloading element so that the second packet is offloaded at the new offloading element;

sending an offloading halt message to the offloading element to stop offloading the second packet at the offloading element; and

sending a handover instruction message to the new offloading element to offload the second data packet at the new offloading element, wherein the handover instruction message includes an identification of the second packet.

7. The method of claim 1,

wherein the offload query message includes an identification of a data path over which the discovery message was received in order to provide the identification of the selected data packets.

8. The method of claim 1, further comprising:

receiving at the gateway the offload query message over a tunnel, wherein the tunnel is identified by a TEID and the offload query message includes a call correlation;

retrieving the call correlation from the offload query message and determining that the call correlation matches the TEID of the tunnel, and

sending the offloading instruction message to the offloading element.

9. The method of claim 1, further comprising sending the discovery message by the gateway to an Internet protocol (IP) address associated with the selected packets.

10. The method of claim 1, wherein the offload query message is sent on all tunnels associated with the selected packets so that the gateway receives at least one offload query message and discovers that the offloading element is serving the selected packets.

11. A router, physically separated from a gateway, comprising:

an interface that is configured to provide communication with a base station, the gateway, and an Internet, to receive a first packet from the base station and transmit the first packet to the gateway, and further configured to receive a second packet from the gateway and transmit the second packet to the base station;

a module that is configured to;

receive a discovery message from the gateway,

send, to the gateway, an offload query message including an indication that the router serves packets selected by the gateway to be offloaded,

receive an offloading instruction message from the gateway, the offloading instruction message including an identification of the selected packets to be offloaded to the Internet,

inspect the first packet to determine that an identification of the first packet matches the identification of the selected packets in the offloading instruction message,

de-capsulate the first packet,

translate a network address in the de-capsulated first packet, and

offload the de-capsulated and network-address-translated first packet to the Internet.

12. The router of claim 11, wherein the identification of the selected packets in the offloading instruction message includes a TEID of a tunnel associated with the selected packets.

13. The router of claim 11, wherein the offload query message includes a call correlation that is used at the gateway to verify that the offload query message is sent by the router.

14. The router of claim 11, wherein the offload query message is sent on all tunnels associated with the selected packets so that the gateway receives at least one offload query message.

15. The router of claim 11, wherein the discovery message is sent by the gateway to an IP address associated with the selected packets.

19. The router of claim 11, wherein the offload query message includes an identification of a data path over which the discovery message was received in order to provide the identification of the selected data packets.

16. Logic encoded on one or more non-transitory tangible media for execution and when executed operable to cause an apparatus to:

receive a discovery message from a gateway;

send an offload query message including an indication that the apparatus serves data packets selected by the gateway to be offloaded;

receive an offloading instruction message from the gateway, wherein the offloading instruction message includes an identification of the selected packets to be offloaded to an Internet;

inspect a first packet to determine that an identification of the first packet matches the identification of the selected packets in the offloading instruction message;

de-capsulate the first packet;

translate a network address in the de-capsulated first packet; and

offload the de-capsulated and network-address-translated first packet to the Internet.

17. The logic of claim 16, wherein the identification of the selected packets in the offloading instruction message includes a TEID of a tunnel associated with the selected packets.

18. The logic of claim 16, wherein the discovery message is sent from the gateway to an IP address associated with the selected packets.

20. The logic of claim 16, wherein the offload query message includes an identification of a data path over which the discovery message was received in order to provide the identification of the selected data packets.