Autonomic reassociation of clients in a wireless local area network

• US 7,652,995 B2
• Filed: 12/19/2003
• Issued: 01/26/2010
• Est. Priority Date: 12/19/2003
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Cromer, Daryl Carvis, Locker, Howard Jeffrey, Jakes, Philip John
• Primary Examiner(s): Moe; Aung S
• Assistant Examiner(s): Alia; Curtis A
• Application Number:
  US10/742,422
• Publication Number:
  US 20050135249A1
• Time in Patent Office: 2,230 Days
• Field of Search: 370229-232, 370235-237, 370216-218, 370/221, 455/422.1, 455/423, 455/424, 455/445
• US Class Current: 370/235
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 36/22 for handling the traffic
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A wireless network access point is described which provides the resources of a backbone network to wireless clients. The access point is able to detect a degraded condition on the backbone network. Upon detecting the degraded condition, the access point transmits or broadcasts a reassociation request to one or more clients associated with the access point. In addition, the rate at which new associations are made is halted or reduced during the degraded backbone condition. In one embodiment, the association rate is reduced by increasing the interval between beacons transmitted by the access point which identify the access to the backbone network.

Claims

1. Apparatus comprising:

a wired network interface;

a wireless network interface which transmits a series of beacons according to a first interval, wherein each beacon identifies access capability through said wired network interface, and which associates clients through the wireless network interface for access through said wired network interface, the wireless network interface having a register for storing a variable which affects the operation of the wireless network interface; and

a flow controller which is coupled to said wired network interface and said wireless network interface and which detects a degraded condition on said wired network interface that indicates a degradation on a wired network to which the wired network interface is connected and initiates the broadcast of a reassociation request across said wireless network interface in response to the detection on said wired network interface;

wherein said flow controller stores only a single bit sized first value in the register in response to the degradation detected on said wired network interface and wherein said wireless network interface increases the interval between the beacon transmissions according to a second interval which is longer than the first interval in response to the first value being stored in the register; and

wherein the degraded condition is selected from the group consisting of a reduced network throughput condition and a network outage condition.

2. Apparatus of claim 1 wherein said flow controller stores a bit sized second value in the register in response to the degradation detected on said wired network interface and wherein said wireless network interface halts beacon transmissions while the second value is stored in the register.

3. Apparatus of claim 1 wherein said flow controller stores a third value in the register in response to the degradation detected on said wired network interface and wherein said wireless network interface refuses the association of clients while the third value is stored in the register;

wherein clients provided on said wireless network interface actively beacon in attempting to associate.

4. A method comprising:

monitoring traffic on a wired network;

transmitting a series of beacons by a wireless network interface over a wireless network according to a first interval, wherein each beacon identifies access capability to the wired network;

associating clients on the wireless network for access to the wired network;

detecting a degraded condition on the wired network based on said monitoring, the wired network being a backbone network, wherein the degraded condition is selected from the group consisting of a reduced network throughput condition and a network outage condition;

storing only a single bit sized first value in a register in response to each degraded condition detected on said wired network interface;

increasing the interval between said beacon transmissions according to a second interval which is longer than the first interval in response to said first value being stored in the register; and

broadcasting a reassociation request to the associated clients on the wireless network in response to said detection on the wired network.

5. The method of claim 4 further comprising:

halting said beacon transmissions in response to said detection on the wired network.

6. The method of claim 4 further comprising:

denying further association of clients on the wireless network in response to said detection on the wired network;

wherein the client attempts association by actively beaconing for access to the wired network.

7. A computer program product encoded on a computer readable storage medium comprising:

computer readable program code stored therein, the computer readable program code in said computer program being effective to;

monitor traffic on a wired network;

transmit a series of beacons over a wireless network according to a first interval, wherein each beacon identifies access capability to the wired network;

associate clients on the wireless network for access to the wired network;

detect a degraded condition on the wired network based on said monitoring, the wired network being a backbone network, wherein the degraded condition is selected from the group consisting of a reduced network throughput condition and a network outage condition;

store only a single bit sized first value in a register in response to each degraded condition detected on said wired network interface;

broadcast a reassociation request to the associated clients on the wireless network in response to said detection on the wired network; and

increase the interval between said beacon transmissions according to a second interval which is longer than the first interval in response to said first value being stored in the register.

8. The computer program product of claim 7 wherein the code is further effective to:

halt said beacon transmissions in response to said detection on the wired network.

9. The computer program product of claim 7 wherein the code is further effective to:

deny further association of clients on the wireless network in response to said detection on the wired network;

wherein the client attempts association by actively beaconing for access.