Quality of service support for A/V streams

• US 20070248100A1
• Filed: 04/25/2006
• Published: 10/25/2007
• Est. Priority Date: 04/25/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Sundaram, Rajesh, Jourdain, Mathias, Zuberi, Khawar
• Granted Patent: US 7,693,157 B2
• Time in Patent Office: Days
• US Class Current: 370/395.410
• CPC Class Codes: H04L 43/50 Testing arrangements
• CPC Class Codes: H04L 45/125 based on throughput or bandwidth
• CPC Class Codes: H04L 45/302 Route determination based on requested QoS
• CPC Class Codes: H04L 45/70 Routing based on monitoring results
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/762 triggered by the network
• CPC Class Codes: H04L 47/803 Application aware
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data
• CPC Class Codes: H04L 47/824 Applicable to portable or mobile terminals

Abstract

An access control mechanism in a network connecting one or more sink devices to a server providing audio/visual data (A/V) in streams. As a sink device requests access, the server measures available bandwidth to the sink device. If the measurement of available bandwidth is completed before the sink device requests a stream of audio/visual data, the measured available bandwidth is used to set transmission parameters of the data stream in accordance with a Quality of Service (QoS) policy. If the measurement is not completed when the data stream is requested, the data stream is nonetheless transmitted. In this scenario, the data stream may be transmitted using parameters computed using a cached measurement of the available bandwidth to the sink device. If no cached measurement is available, the data stream is transmitted with a low priority until a measurement can be made. Once the measurement is available, the transmission parameters of the data stream are re-set. With this access control mechanism, A/V streams may be provided with low latency but with transmission parameters accurately set in accordance with the QoS policy.

Claims

1. A method of operating a first device (134) adapted to provide a stream of data over a network, the method comprising:

a) associating (212) with a second device (160, 162) adapted to receive a data stream;

b) following associating with the second device and prior to receipt of a request to transfer a stream of data to the second device, initiating bandwidth measurement (253) to measure an available bandwidth between the first device and the second device; and

c) in response to receipt of a request to transfer a stream of data to the second device, transmitting (226) a stream of data using parameters to control the bandwidth consumed by the data stream, wherein

i) the parameters are set in a first way (326) if the bandwidth measurement is completed prior to receipt of a request to transmit a data stream, the first way being based on measured available bandwidth; and

ii) the parameters are set in a second way (332, 334), different than the first way, if the bandwidth measurement is not completed prior to receipt of the request to transfer the data stream.

2. The method of claim 1, wherein the second way (323) comprises selecting transmission parameters based at least in part on a cached measurement of available bandwidth.

3. The method of claim 1, wherein the second way (334) comprises selecting transmission parameters that cause the data stream to be transmitted with a low priority.

4. The method of claim 1, wherein the second way comprises:

A) selecting transmission parameters based at least in part on a cached measurement of available bandwidth between the first device and the second device when the cached measurement is available (332); and

B) selecting transmission parameters that cause the data stream to be transmitted with a low priority when the cached measurement is not available (334).

5. The method of claim 1, wherein transmitting the data stream comprises transmitting the data stream over a wireless network (146, 150).

6. The method of claim 1, wherein transmitting the data stream comprises transmitting a data stream representing audio and video information (146, 150).

7. The method of claim 1, further comprising repeating the measurement of available bandwidth and altering the parameters to control the bandwidth consumed by the data stream (328).

8. A method of operating a first device (134) adapted to provide streams of data over a network, the method comprising:

a) associating with a second device (160, 162) adapted to receive a data stream;

b) in response to associating with the second device and prior to receipt of a request to transfer a stream of data to the second device, transmitting probes (214) adapted to measure an available bandwidth between the first device and the second device; and

c) in response to receipt of a request to transfer a stream of data to the second device, transmitting the stream of data using parameters set based at least in part of a measurement of the available bandwidth made using the transmitted probes (326).

9. The method of claim 8, wherein associating with a second device comprises receiving a source discovery message from the second device (210).

10. The method of claim 8, wherein associating with a second device comprises receiving an authentication message from the second device (210).

11. The method of claim 8, additionally comprising transmitting menu information (314) to the second device, the menu information comprises a plurality of user-selectable menu entries and wherein receiving a request to transfer the stream of data comprises receiving an indication that a user has selected a menu entry of the plurality of user-selectable menu entries (320).

12. The method of claim 11, wherein probes are transmitted between the transmitting of menu information (314) and the receiving a request to transfer the stream of data (320).

13. The method of claim 11, additionally comprising transmitting menu information (320) to the sink device concurrently with transmitting the probes (214).

14. The method of claim 13, wherein transmitting the stream of data comprises transmitting a stream of audio/visual data (146, 150).

15. A computer-readable medium adapted for use with a first device (134) that provides a stream of data over a network, the computer-readable medium comprising computer-executable instructions for:

a) associating with a second device (160, 162) adapted to receive a data stream;

b) measuring available bandwidth between the first device and the second device (253), wherein measuring of the available bandwidth begins prior to a request (222) for transmission of a data stream to the second device; and

c) setting parameters of transmission of the data stream (224), the setting being performed in a first way (326) based on a measured available bandwidth if the available bandwidth measurement is completed and the setting being performed in a second way (332,334) if the available bandwidth measurement is not completed.

16. The computer-readable medium of claim 15, further comprising computer-executable instructions for, when the available bandwidth measurement is not completed:

d) completing the measuring of available bandwidth between the first device and the second device after a request for transmission of a data stream to the second device (253); and

e) altering the set (253) parameters of transmission of the data stream based on the completed measurement (326).

17. The computer-readable medium of claim 15, wherein setting parameters of transmission of the data stream in the second way comprises setting the priority of packets carrying data of the data stream to a first priority (334).

18. The computer-readable medium of claim 17, further comprising computer-executable instructions for, when the available bandwidth measurement is not completed:

d) completing the measuring of available bandwidth between the first device and the second device after a request for transmission of a data stream to the second device (253); and

e) if the measured available bandwidth is sufficient to transmit the data stream, setting the priority of packets carrying data of the data stream to a second priority, the second priority being higher than the first (326).

19. The computer-readable medium of claim 15, wherein setting parameters of transmission of the data stream in the second way comprises setting parameters of transmission based on a cached measurement of available bandwidth between the first device and the second device (332).

20. The computer-readable medium of claim 15, wherein the computer-readable medium is a portion of a multi-media computer (134) connected to the Internet (170).