Admission control method for data communications over peripheral buses

• US 6,658,512 B1
• Filed: 09/28/2000
• Issued: 12/02/2003
• Est. Priority Date: 09/28/2000
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Gokulrangan, Venkat R.
• Primary Examiner(s): Lefkowitz, Sumati
• Application Number:
  US09/671,236
• Time in Patent Office: 1,160 Days
• Field of Search: 709/227-229, 370/230-234, 710/107-125
• US Class Current: 710/117
• CPC Class Codes: H04L 47/11 Identifying congestion
• CPC Class Codes: H04L 47/13 in a LAN segment, e.g. ring or bus
• 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 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/801 Real time traffic
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data
• CPC Class Codes: H04L 47/83 based on usage prediction

Abstract

A method adaptively controls admission of a plurality of resources to a peripheral bus having a finite bandwidth. It monitors the actual data transfer rate of each resource having a bandwidth guarantee on the peripheral bus for data communications. Upon receiving a request for admission to the peripheral bus from an additional resource, a utilization value representative of the extent to which the plurality of resources utilizes the guaranteed bandwidth on the peripheral bus is obtained. The additional resource is admitted to the peripheral bus if the utilization value indicates that the amount of unutilized bandwidth on the peripheral bus is approximately sufficient to satisfy the data transfer rate of the additional resource.

Claims

1. A communications system controlling the admission of resources to a peripheral bus in the communications system, the communications system comprising:

a peripheral bus having a finite bandwidth;

a plurality of resources, connected to the peripheral bus, and configured to send and/or receive data over the peripheral bus; and

a communications controller connected to the peripheral bus, said communications controller adapted to;

monitor the actual data transfer rate on the peripheral bus of each of said plurality of resources having a bandwidth guarantee on the peripheral bus for data communications;

obtain a utilization value representative of the extent to which the plurality of resources utilizes the guaranteed bandwidth on the peripheral bus upon receiving a quasi-isochronous request for admission to the peripheral bus from an additional resource; and

admit the additional resource to the peripheral bus if the utilization value indicates that the amount of unutilized bandwidth on the peripheral bus is approximately sufficient to satisfy the data transfer rate of the additional resource.

2. The communications system recited in claim 1, wherein if the additional resource is admitted but the unutilized bandwidth is insufficient to transfer all of the bits of the additional resource, then the extraneous bits are dropped without being transferred over the peripheral bus.

3. The communications system recited in claim 1, wherein the step of obtaining a utilization value comprises monitoring the data traffic on the peripheral bus with an admission control component on a host system.

4. The communications system recited in claim 3, wherein the admission control component manages a state diagram.

5. The communications system recited in claim 4, wherein the states of the state diagram respectively correspond to different degrees of bandwidth utilization.

6. The communications system recited in claim 5, wherein the admission control component maintains a historical analysis of the data traffic on the peripheral bus.

7. The communications system recited in claim 1, wherein the peripheral bus is a USB bus.

8. The communications system recited in claim 7, wherein one of the plurality of resources contains a codec and sends and/or receives data having a variable bit rate.

9. The communications system of claim 1, wherein said plurality of resources comprise a plurality of Universal Serial Bus (USB) devices and said peripheral bus comprises a USB bus.

10. The communications system of claim 1, wherein obtaining the utilization value is performed only for the quasi-isochronous request.

11. The communications system of claim 1, wherein monitoring the actual data transfer rate comprises monitoring actual isochronous bandwidth being used on the peripheral bus.

12. A method of adaptively controlling admission of a plurality of resources to a peripheral bus having a finite bandwidth, said method comprising:

for each one of a plurality of resources having a bandwidth guarantee for data communications on the peripheral bus, monitoring the actual data transfer rate on the peripheral bus of each one of said plurality of resources;

upon receiving a quasi-isochronous request for admission to the peripheral bus from an additional resource, obtaining a utilization value representative of the extent to which the plurality of resources utilizes the guaranteed bandwidth on the peripheral bus for data communications; and

admitting the additional resource to the peripheral bus if the utilization value indicates that the amount of unutilized bandwidth on the peripheral bus is approximately sufficient to satisfy the data transfer rate of the additional resource.

13. The method recited in claim 12, wherein if the additional resource is admitted but the unutilized bandwidth is insufficient to transfer all of the bits of the additional resource, then the extraneous bits are dropped without being transferred.

14. The method recited in claim 12, wherein the step of obtaining a utilization value comprises monitoring the data traffic on the peripheral bus with an admission control component on a host system.

15. The method recited in claim 14, wherein the admission control component manages a state diagram.

16. The method recited in claim 15, wherein the states of the state diagram respectively correspond to different degrees of bandwidth utilization.

17. The method recited in claim 16, wherein the admission control component maintains a historical analysis of the data traffic on the peripheral bus.

18. The method recited in claim 12, wherein said plurality of resources comprise a plurality of Universal Serial Bus (USB) devices and said peripheral bus comprises a USB bus.

19. The method recited in claim 12, wherein obtaining the value is performed only for the quasi-isochronous request.

20. The method recited in claim 12, wherein monitoring the actual data transfer rate comprises monitoring actual isochronous bandwidth being used on the peripheral bus.

21. A computer program stored in a tangible medium, the computer program, when executed, causing a processing system to carry out a method comprising:

for each one of a plurality of resources having a bandwidth guarantee for data communications on the peripheral bus, monitoring the actual data transfer rate on the peripheral bus of each one of said plurality of resources;

upon receiving a quasi-isochronous request for admission to the peripheral bus from an additional resource, obtaining a utilization value representative of the extent to which the plurality of resources utilizes the guaranteed bandwidth on the peripheral bus for data communications; and

admitting the additional resource to the peripheral bus if the utilization value indicates that the amount of unutilized bandwidth on the peripheral bus for data communications is approximately sufficient to satisfy the data transfer rate of the additional resource.

22. The computer program recited in claim 21, wherein if the additional resource is admitted but the unutilized bandwidth is insufficient to transfer all of the bits of the additional resource, then the extraneous bits are dropped without being transferred.

23. The computer program recited in claim 21, wherein the step of obtaining a utilization value comprises monitoring the data traffic on the peripheral bus with an admission control component on a host system.

24. The computer program recited in claim 23, wherein the admission control component manages a state diagram.

25. The computer program recited in claim 24, wherein the states of the state diagram respectively correspond to different degrees of bandwidth utilization.

26. The computer program recited in claim 25, wherein the admission control component maintains a historical analysis of the data traffic on the peripheral bus.

27. The computer program recited in claim 21, wherein the utilization value is performed only for the quasi-isochronous request.

28. The computer program recited in claim 27, wherein said specific type of transfer request comprises a quasi-isochronous transfer request.

29. The computer program recited in claim 21, wherein monitoring the actual data transfer rate comprises monitoring actual isochronous bandwidth being used on the peripheral bus.