Detecting and diagnosing performance problems in a wireless network through neighbor collaboration

• US 20060068769A1
• Filed: 01/31/2005
• Published: 03/30/2006
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bahl, Paramvir, Chandra, Ranveer, Adya, Atul, Qiu, Lili
• Granted Patent: US 7,603,460 B2
• Time in Patent Office: Days
• US Class Current: 455/418
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Systems and methods are described for detecting and diagnosing performance problems in wireless communications networks. Diagnostic programs execute on a wireless device, neighboring devices, and a wireless access point to collaborate in diagnosing network problems. The neighboring devices eavesdrop on a diagnostic session between the device and the access point to determine problems at the device, the access point, and in the wireless medium. Data from the eavesdropping devices can be summarized and sent to a network administrator for further action. The diagnostic programs are described to contain a passive component for detecting problems, and an active component for running the diagnostic techniques.

Claims

1. A computer-readable medium including computer-executable instructions facilitating diagnosis of communications problems experienced by a first wireless device in a wireless network, wherein the first wireless device is either a wireless computing device or a wireless access point, the computer-executable instructions executing on the first wireless device and performing the steps of:

determining that a communications problem exists in the wireless network;

broadcasting a request to one or more neighboring wireless devices for assistance in diagnosing the communications problem;

responding to snoop requests sent by a second wireless device in a diagnostic session; and

receiving information about the diagnostic session from at least one of the neighboring wireless devices.

2. The computer-readable medium of claim 1, the computer-executable instructions further performing the step of:

sending snoop requests to the second wireless device in the diagnostic session.

3. The computer-readable medium of claim 1 wherein the information about the diagnostic session contains estimates of one or more of packet delay or packet loss rates.

4. The computer-readable medium of claim 1 wherein the first wireless device is a wireless computing device, and wherein the second wireless device is a wireless access point.

5. The computer-readable medium of claim 1, the computer-executable instructions further performing the step of:

determining, using the information about the diagnostic session, the extent to which the communications problem is caused by one or more of;

the first wireless device;

the second wireless device;

or the wireless medium between the first wireless device and the second wireless device.

6. The computer-readable medium of claim 1, the computer-executable instructions further performing the step of:

reporting results of the diagnostic session to a network administrator.

7. A diagnostic system for diagnosing problems on a computer network including both a wireless portion between a first wireless computing device and a wireless access point and a wired portion between the access point and an infrastructure network, the diagnostic system comprising:

a diagnostic client program running on the first wireless computing device; and

a diagnostic access point program running on the wireless access point, the diagnostic access point program communicating with the diagnostic client program to determine whether a network connection problem occurs in the wired portion or the wireless portion of the network.

8. The diagnostic system of claim 7 wherein the diagnostic client program comprises:

a monitoring component for detecting network connection problems; and

a diagnosis component for diagnosing network connection problems occurring in the wireless portion of the network;

wherein the diagnosis component is activated only when the monitoring component detects a network connection problem

9. The diagnostic system of claim 8 wherein the monitoring component estimates the loss rate of data packets sent and received by the first wireless computing device, and activates the diagnosis component if the estimated loss rate is above a threshold percentage value.

10. The diagnostic system of claim 8 wherein the monitoring component:

computes the delay time of data packets sent by the first wireless computing device;

estimates the delay time of data packets received by the first wireless computing device; and

activates the diagnosis component if the computed or estimated delay time for at least a threshold number of data packets is sufficiently high.

11. The diagnostic system of claim 7 wherein the diagnostic access point program:

estimates the delay time within the wired portion of the network for one or more packets sent by the first wireless computing device to one or more remote hosts on the infrastructure network; and

transmits the estimated delay time to the diagnostic client program;

wherein the diagnostic client program uses the transmitted estimated delay time to estimate the delay time within the wireless portion of the network.

12. The diagnostic system of claim 7 further comprising one or more additional wireless computing devices, each running a diagnostic client program accumulating performance data for the wireless portion of the network by monitoring wireless network traffic between the first wireless computing device and the wireless access point, wherein the one or more additional wireless computing devices transmits a summary of its accumulated performance data to the first wireless computing device.

13. The diagnostic system of claim 13 wherein the first wireless computing device uses the accumulated performance data to determine the extent to which the communications problem is caused by one or more of:

the first wireless computing device;

the wireless access point;

or the wireless medium between the first wireless computing device and the wireless access point.

14. A computer-readable medium including computer-executable instructions facilitating diagnosis of communications problems experienced by a first wireless computing device in a wireless network, the computer-executable instructions executing on a second wireless computing device and performing the steps of:

receiving a request for diagnostic help from the first wireless computing device;

accumulating performance data by monitoring the wireless environment and traffic flow between the first wireless computing device and one or more wireless access points; and

transmitting a summary of the accumulated performance data.

15. The computer-readable medium of claim 14 wherein transmitting a summary comprises transmitting to the first wireless computing device.

16. The computer-readable medium of claim 14, the computer-executable instructions further performing the step of:

configuring the second wireless computing device to enter a promiscuous mode.

17. The computer-readable medium of claim 14, the computer-executable instructions further performing the step of requesting a diagnostic access point program running on a wireless access point to begin a diagnostic protocol with the first wireless computing device.

18. The computer-readable medium of claim 14 wherein accumulating performance data comprises estimating the communications delay caused by the first wireless computing device.

19. The computer-readable medium of claim 18 wherein the traffic flow comprises a snoop request sent by the wireless access point and a corresponding snoop response sent by the first wireless computing device, and the communications delay is estimated to be the amount of time between hearing the snoop request and the corresponding snoop response.

20. The computer-readable medium of claim 14 wherein accumulating performance data comprises estimating the communications delay caused by the wireless access point.