Predictive roaming between subnets

• US 8,614,989 B2
• Filed: 04/20/2012
• Issued: 12/24/2013
• Est. Priority Date: 05/14/2008
• Status: Active Grant

• Current Assignee: Extreme Networks, Inc.
• Original Assignee: Aerohive Networks Incorporated (Extreme Networks, Inc.)
• Inventors: Liu, Changming, Kang, Yong, Zeng, Jianlin, Reddy, Sreekanth
• Primary Examiner(s): Faroul, Farah
• Application Number:
  US13/452,437
• Publication Number:
  US 20120201201A1
• Time in Patent Office: 613 Days
• Field of Search: 370/328, 370/331, 370/332
• US Class Current: 370/331
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 63/0876 based on the identity of the terminal or configuration, e.g. MAC address, hardware or software configuration or device fingerprint
• CPC Class Codes: H04W 12/04 Key management, e.g. using generic bootstrapping architecture [GBA]
• CPC Class Codes: H04W 28/088 among core entities
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/0016 Hand-off preparation specially adapted for end-to-end data sessions
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/0066 of control information between different types of networks in order to establish a new radio link in the target network
• CPC Class Codes: H04W 36/008375 based on historical data
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 76/12 Setup of transport tunnels
• CPC Class Codes: H04W 76/22 Manipulation of transport tunnels
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 8/02 Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 8/087 for preserving data network PoA address despite hand-offs
• CPC Class Codes: H04W 8/18 Processing of user or subscriber data, e.g. subscribed services, user preferences or user profiles; Transfer of user or subscriber data
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A network device of a subnet determines predictive roaming information for a wireless client. Predictive roaming information can identify the wireless client and a home network subnet of the wireless client. The network device provides predictive roaming information associated with a wireless client to neighboring subnets. Neighboring subnets store received predictive roaming information, and use the predictive roaming information if the wireless client roams to them.

Claims

1. A method comprising:

maintaining a first home agent address, of a first home agent of a first subnet, at a second home agent of a second subnet;

receiving, at a wireless access point of the second subnet, predictive roaming information from the first subnet, wherein the predictive roaming information includes;

a first address suitable to uniquely identify a first wireless client within a network comprising the first subnet and the second subnet, and a second address suitable to uniquely identify the first wireless client within the first subnet and to associate the first wireless client with the first subnet;

receiving, at the wireless access point, identifying information from the first wireless client;

matching, at the wireless access point, the first address in the predictive roaming information with the identifying information, wherein a match is indicative of the first wireless client having roamed to the second subnet;

matching, at the wireless access point, the second address in the predictive roaming information with the identifying information, wherein a match is indicative of the first wireless client having roamed from the first subnet;

when the first wireless client has roamed from the first subnet, obtaining at the wireless access point, from the second home agent, the first home agent address of the first home agent;

establishing a tunnel between the wireless access point of the second subnet and the first home agent of the first subnet, using the first home agent address obtained, for carrying network traffic associated with the first wireless client.

2. The method of claim 1, wherein the first home agent is implemented on another wireless access point.

3. The method of claim 1, wherein the first home agent is implemented on a network switch.

4. The method of claim 1, wherein the first home agent is implemented on a dedicated device.

5. The method of claim 1, wherein the first home agent is implemented on a computer system.

6. The method of claim 1, wherein the first address includes a Medium Access Control (MAC) address of the first wireless client.

7. The method of claim 1, wherein the second address includes an Internet Protocol (IP) address compliant with a subnet mask of the first subnet.

8. The method of claim 1, further comprising receiving the first subnet predictive roaming information from a first wireless access point of the first subnet.

9. The method of claim 1, further comprising receiving the first subnet predictive roaming information indirectly.

10. The method of claim 1, wherein the predictive roaming information includes a session key, further comprising establishing, using the session key, a wireless connection between a second wireless access point of the second subnet and the first wireless client.

11. The method of claim 1, further comprising establishing the tunnel between a first wireless access point of the first subnet and a second wireless access point of the second subnet.

12. The method of claim 1, wherein the tunnel is a generic routing encapsulation (GRE) tunnel.

13. The method of claim 1, further comprising using the tunnel to carry network traffic for a second wireless client with a home address in the first subnet.

14. The method of claim 1, further comprising maintaining a third home agent address of a third home agent of a third subnet at the second subnet.

15. The method of claim 1, wherein the identifying information is first identifying information, further comprising,

receiving second identifying information from a second wireless client;

querying the first home agent for information associated with the second wireless client;

receiving a response from the first home agent that the second wireless client was previously on the first subnet.

16. The method of claim 15, further comprising using the tunnel to carry network traffic associated with the second wireless client.

17. The method of claim 15, wherein the tunnel is a first tunnel, further comprising establishing a second tunnel, between the second subnet and the first home agent of the first subnet, for carrying network traffic associated with the second wireless client.

18. The method of claim 1, further comprising:

assigning the first wireless client a third address suitable to uniquely identify the second subnet within the network if the first wireless client is inactive for a period of time;

discarding the tunnel if not in use by other wireless clients.

19. A computer program product, embodied in a non-transitory computer-readable medium, including instructions for:

maintaining a first home agent address, of a first home agent of a first subnet, at a second home agent of a second subnet;

receiving, at a wireless access point of the second subnet, predictive roaming information from the first subnet, wherein the predictive roaming information includes;

a first address suitable to uniquely identify a first wireless client within a network comprising the first subnet and the second subnet, and a second address suitable to uniquely identify the first wireless client within the first subnet and to associate the first wireless client with the first subnet;

receiving, at the wireless access point, identifying information from the first wireless client;

matching, at the wireless access point, the first address in the predictive roaming information with the identifying information, wherein a match is indicative of the first wireless client having roamed to the second subnet;

matching, at the wireless access point, the second address in the predictive roaming information with the identifying information, wherein a match is indicative of the first wireless client having roamed from the first subnet;

when the first wireless client has roamed from the first subnet, obtaining at the wireless access point, from the second home agent, the first home agent address of the first home agent;

establishing a tunnel between the wireless access point of the second subnet and the first home agent of the first subnet, using the first home agent address obtained, for carrying network traffic associated with the first wireless client.

20. A system comprising:

a means for maintaining a first home agent address, of a first home agent of a first subnet, at a second home agent of a second subnet;

a means for receiving, at a wireless access point of the second subnet, predictive roaming information from the first subnet, wherein the predictive roaming information includes;

a first address suitable to uniquely identify a first wireless client within a network comprising the first subnet and the second subnet, and a second address suitable to uniquely identify the first wireless client within the first subnet and to associate the first wireless client with the first subnet;

a means for receiving, at the wireless access point, identifying information from the first wireless client;

a means for matching, at the wireless access point, the first address in the predictive roaming information with the identifying information, wherein a match is indicative of the first wireless client having roamed to the second subnet;

a means for matching, at the wireless access point, the second address in the predictive roaming information with the identifying information, wherein a match is indicative of the first wireless client having roamed from the first subnet;

a means for obtaining at the wireless access point, from the second home agent, the first home agent address of the first home agent when the first wireless client has roamed from the first subnet;

a means for establishing a tunnel between the wireless access point of the second subnet and the first home agent of the first subnet, using the first home agent address obtained, for carrying network traffic associated with the first wireless client.