Communication device client update system and method

• US 7,529,256 B2
• Filed: 07/08/2005
• Issued: 05/05/2009
• 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 M.
• Primary Examiner(s): HO, DUC CHI
• Application Number:
  US11/178,141
• Publication Number:
  US 20070008981A1
• Time in Patent Office: 1,397 Days
• Field of Search: None
• US Class Current: 370/401
• 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 method comprising:

broadcasting a first address resolution protocol (ARP) request;

adding a client indication to a client tracking list, wherein the client indication corresponds to a response to the first address resolution protocol request from a client device;

sending a second address resolution protocol request to the client device; and

determining a status of the client device with respect to the client tracking list based on at least one action by the client device with regard to the second address resolution protocol request, wherein the status of the client device is forwarded to one or more upstream devices and wherein the one or more upstream devices is configured to incorporate the status in a connectivity list.

2. The method of claim 1, further comprising:

running a client list flush timer for establishing periodic status updates; and

sending the second address resolution protocol request to the client device when the client list flush timer has expired.

3. The method of claim 1, wherein the determining of the status of the client device with respect to the client tracking list further comprises:

leaving the client device on the client tracking list when the client device responds to the second address resolution protocol request; and

removing the client indication from the client tracking list when the client device does not respond to the second address resolution protocol request.

4. The method of claim 1, wherein the client indication is a media access control (MAC) address and the client tracking list is a media access control address list.

5. The method of claim 1, wherein the address resolution protocol request is forwarded across a wireless to wired protocol boundary.

6. The method of claim 1, wherein the 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. The method of claim 1, wherein the status of the client device with respect to an access point connectivity list is based on the action by the client device with regard to the second address resolution protocol request.

8. The method of claim 1, wherein the client tracking list is a list for tracking client devices communicatively coupled to a workgroup bridge device.

9. A device comprising:

an interface to communicate with one or more client devices; and

a client tracking component to broadcast a first address resolution protocol (ARP) request through the interface and to track a status of at least one client device based on a response to the first address resolution protocol request received from a client device, wherein the client tracking component is configured to send a second address resolution protocol request to the client device and to update a status of the client device according to at least one action taken by the client device with regard to the second address resolution protocol request, wherein the status of the client device is forwarded to one or more upstream devices and wherein the one or more upstream devices is configured to incorporate the status in a connectivity list.

10. The device of claim 9, wherein the client tracking component adds an entry associated with the client device to a client tracking list, and sends the second address resolution protocol request to the client device, and wherein the client tracking component alters the client tracking list by removing the entry when the client device does not respond to the second address resolution protocol request.

11. The device of claim 9, wherein the client tracking component tracks media access control addresses of the one or more client devices communicatively coupled to the device.

12. The device of claim 9, wherein the device is a router.

13. The device of claim 9, wherein the client tracking component determines when a predetermined amount of time has expired since receiving a communication from client devices that have responded to the first address resolution protocol request and sends the second address resolution protocol request to the client devices with associated expired times.

14. The device of claim 9, wherein the client tracking component stops tracking the client devices that do not respond to the second address resolution protocol request.

15. The device of claim 10, wherein the client tracking list includes media access control addresses.

16. A system comprising:

means for broadcasting a first address request;

means for tracking one or more client devices that respond to the first address request in a client tracking list;

means for sending a second address request to at least one client device being tracked;

means for updating a status of the client device tracked in client tracking list based on at least one action by the client device responsive to the second address request; and

means for forwarding the status to one or more upstream devices for incorporation in a connectivity list.

17. A device comprising:

an interface to communicate with one or more client devices; and

a client tracking component to broadcast a first address resolution protocol (ARP) request, to add a client indication to a client tracking list, wherein client indication corresponds to a client device responding to the first address resolution protocol request, to send a second address resolution protocol request to the client device, and to determine a status of the client device with respect to the client tracking list based on at least one action taken by the client in response to receiving the second address resolution protocol request, wherein the client tracking component is configured to forward the status to one or more upstream devices for incorporation in a connectivity list.

18. A device of claim 17 wherein the client tracking component is configured to send the second address resolution protocol request to the client device after a client tracking list flush timer has expired, and wherein the client tracking component is configured to leave the client device on the client tracking list when the client device responds to the second address resolution protocol request, and remove the client indication from the client tracking list when the client device does not respond to the second address resolution protocol request.

19. A device of claim 17 wherein the second address resolution protocol request is sent across a wireless to wired protocol boundary.