Communication device client update system and method

• US 20070008981A1
• Filed: 07/08/2005
• Published: 01/11/2007
• Est. Priority Date: 07/08/2005
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Pathan, Arnavkumar
• Granted Patent: US 7,529,256 B2
• Time in Patent Office: Days
• US Class Current: 370/395.540
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/02 Data link layer protocols
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A system and method that facilitates client address updating in a communication network is presented. Client address lists are maintained and updated with a single mechanism deployed flexibly across different communication environment boundaries. Network devices update address lists for clients deployed across boundaries of wireless communication environments (e.g., an IEEE 802.11 compliant environment) and wired communication environments (e.g., an IEEE 802.3 compliant environment). Interruptions and delays in information communication due to stale client registration and tracking activities are minimized.

Claims

1. A communication network update method comprising:

broadcasting a first address resolution protocol (ARP) request;

adding a client indication to a client tracking list, wherein said client indication corresponds to a client responding to said first address resolution protocol request;

sending a second address resolution protocol request to said client; and

determining a status of said client with respect to said client tracking list based upon said client'"'"'s action with regard to said second address resolution protocol request.

2. A communication network update method of claim 1 further comprising running a client list flush timer for establishing periodic updates of said status and said second address resolution protocol request is forwarded after said client tracking list flush timer has expired and before taking an action with regard to said status of said client with respect to said client tracking list.

3. A communication network update method of claim 1 wherein said determining said status of said client with respect to said client tracking list further comprises:

leaving said client on said client tracking list if said client responds to said second address resolution protocol request; and

removing said client indication from said client tracking list if said client does not respond to said second address resolution protocol request.

4. A communication network update method of claim 1 wherein said client indication is a media access control (MAC) address and said client tracking list is a media access control address list.

5. A communication network update method of claim 1 wherein said address resolution protocol request is forwarded across a wireless to wired protocol boundary.

6. A communication network update method of claim 1 wherein said address resolution protocol request is forwarded across a boundary spanning an environment compliant with an IEEE 802.11 standard protocol and an environment compliant with an IEEE 802.3 standard protocol.

7. A communication network update method of claim 1 wherein said status of said client with respect to an access point connectivity list is based upon said client'"'"'s action with regard to said second address resolution protocol request.

8. A communication network update method of claim 1 wherein said status of said client is forwarded to upstream devices and said upstream devices incorporate said status in a connectivity list (e.g., router list).

9. A communication network update method of claim 1 wherein said client tracking list is a list for tracking clients communicatively coupled to a workgroup bridge device.

10. A root device comprising:

a wireless communication port for communicating an address resolution protocol request wirelessly to clients communicatively coupled to said rood device;

a wired communication port for communicating said address resolution protocol request via a wire; and

a client tracking component for tracking clients communicatively coupled to said wireless communication port and said wired communication port, wherein said client tracking component utilizes said address resolution protocol request to track said clients communicatively coupled to said wireless communication port and said wired communication port.

11. A root device of claim 10 wherein said client tracking component forwards said address resolution protocol request before altering a client tracking list and alters said client tracking list by removing clients that do not respond to said address resolution protocol request.

12. A root device of claim 10 wherein said client tracking list tracks media access control addresses of said clients communicatively coupled to said root device.

13. A root device of claim 10 wherein said root device is a router.

14. A root device of claim 10 wherein said client tracking component analyzes if a predetermined amount of time has expired since receiving a communication from each of said clients respectively and if said predetermined amount of time has expired said rood device forwards said address resolution protocol request to said respective clients with expired times.

15. A root device of claim 14 wherein said client tracking component stops tracking each of said clients which do not respond to said address resolution protocol request.

16. A root device of claim 10 wherein said client tracking list includes media access control addresses.

17. A network access point comprising:

a means for communicating information with upstream devices;

a means for communicating said information with downstream devices;

a means for tracking clients communicatively coupled via said downstream devices, wherein said means for tracking clients utilizes an address resolution protocol request to track said clients communicatively coupled to said downstream devices.

18. A device comprising:

a wireless communication port for communicating an address resolution protocol request wirelessly to clients communicatively coupled to said device;

a wired communication port for communicating said address resolution protocol request via a wire; and

a client tracking component for performing a communication network update process including;

directing broadcast of a first address resolution protocol (ARP) request;

adding a client indication to a client tracking list, wherein said client indication corresponds to a client responding to said first address resolution protocol request;

directing forwarding of a second address resolution protocol request to said client; and

determining a status of said client with respect to said client tracking list based upon said client'"'"'s action with regard to said second address resolution protocol request.

19. A device of claim 18 wherein said second address resolution protocol request is forwarded after a client tracking list flush timer has expired and said determining said status of said client with respect to said client tracking list further comprises:

leaving said client on said client tracking list if said client responds to said second address resolution protocol request; and

removing said client indication from said client tracking list if said client does not respond to said second address resolution protocol request.

20. A device of claim 18 wherein said address resolution protocol request is forwarded across a wireless to wired protocol boundary.