Flow control in a network environment

• US 7,433,307 B2
• Filed: 11/05/2002
• Issued: 10/07/2008
• Est. Priority Date: 11/05/2002
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Wolrich, Gilbert, Hooper, Donald F., Adiletta, Matthew J., Wilde, Myles J.
• Primary Examiner(s): Wilson; Robert W
• Application Number:
  US10/290,040
• Publication Number:
  US 20040085901A1
• Time in Patent Office: 2,163 Days
• Field of Search: None
• US Class Current: 370/231
• CPC Class Codes: H04L 12/5601 Transfer mode dependent, e.g. ATM
• CPC Class Codes: H04L 2012/561 Star, e.g. cross-connect, concentrator, subscriber group equipment, remote electronics
• CPC Class Codes: H04L 2012/5635 Backpressure, e.g. for ABR
• CPC Class Codes: H04L 2012/5636 Monitoring or policing, e.g. compliance with allocated rate, corrective actions
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/43 Assembling or disassembling of packets, e.g. segmentation and reassembly [SAR]

Abstract

Providing flow control includes receiving at a router an indication of the ability of each one of multiple ports not directly connected to the router to receive data from the router and controlling transmission of data from the router to the multiple ports based at least on the indication.

Claims

1. A method for providing flow control comprising:

receiving multiple vectors at a router, each of the multiple vectors comprising an indication of an availability of a collection of multiple ports not directly connected to the router to receive data from the router;

assembling the multiple vectors into a composite; and

controlling transmission of data from the router to the multiple ports based at least on the composite.

2. The method of claim 1 further comprising transmitting data from the multiple ports to a network.

3. The method of claim 1 further comprising storing the indication at a storage location.

4. The method of claim 1 further comprising transmitting data from the router to one of the multiple ports if the indication indicates that the one of the multiple ports can accept data.

5. The method of claim 1 further comprising changing a rate of data transmission to the multiple ports based on at least the indication.

6. The method of claim 1 in which the indication includes bits indicating whether or not the multiple ports include can accept data.

7. The method of claim 1 further comprising

receiving at the router an additional indication of the availability of additional ports to accept data from the router, and

controlling transmission of data from the router to the additional ports based at least on the additional indication.

8. The method of claim 7 further comprising storing the additional indication at a storage location address contiguous to another storage location address that stores the indication.

9. The method of claim 1 further comprising receiving the indication at the router on a physical port from a device having access to the multiple ports.

10. The method of claim 1 further comprising receiving the indication at the router on a sideband bus from a device having access to the multiple ports.

11. The method of claim 1 further comprising receiving the indication at the router from a Digital Subscriber Line Access Multiplexer having access to the multiple ports.

12. The method of claim 1 in which the data includes a packet.

13. The method of claim 1 in which the multiple ports comprise virtual ports.

14. An article for providing flow control, the article including a machine readable medium having machine executable instructions, the instructions when executed by a machine causing the machine to perform operations comprising:

receiving at a router a first indication of an availability of each one of a first collection of multiple ports that are not directly connected to the router to receive data from the router;

receiving at the router a second indication of an availability of each one of a second collection of multiple ports that are not directly connected to the router to receive data from the router;

storing the first indication and the second indication at contiguous storage location addresses; and

controlling transmission of data from the router to the first collection of multiple ports based at least on the first indication and to the second collection of multiple ports based at least on the second indication.

15. The article of claim 14 further comprising transmitting data from the multiple ports to a network.

16. The article of claim 14 further comprising storing the indication at a storage location.

17. The article of claim 14 further comprising transmitting data from the router to one of the multiple ports if the indication indicates that the one of the multiple ports can accept data.

18. The article of claim 14 further comprising changing a rate of data transmission to the multiple ports based on at least the indication.

19. The article of claim 14 in which the indication includes bits indicating whether or not the multiple ports include can accept data.

20. The article of claim 14 further comprising receiving the indication at the router on a physical port from a device having access to the multiple ports.

21. The article of claim 14 further comprising receiving the indication at the router on a sideband bus from a device having access to the multiple ports.

22. The article of claim 14 further comprising receiving the indication at the router from a Digital Subscriber Line Access Multiplexer having access to the multiple ports.

23. The article of claim 14 further comprising

receiving multiple vectors at the router, each of the multiple vectors indicating the availability of a subset of the multiple ports to receive data from the router;

assembling the multiple vectors into one vector; and

using the one vector to control transmission of data from the router to the multiple ports.

24. The article of claim 14 in which the data includes a packet.

25. The article of claim 14 in which the multiple ports comprise virtual ports.

26. A system for providing flow control comprising:

a device configured to provide multiple ports, each configured to transmit data to a network; and

a router not directly connected to the multiple ports and configured to receive separate indications of an availability of each of the multiple ports to accept data from the router and configured to control transmission of information from the router to the multiple ports based at least on the indication, wherein the router includes a memory mechanism that is accessible by the router and configured to store the indication.

27. The system of claim 26 in which the device includes a Digital Subscriber Line Access Multiplexer.

28. The system of claim 26 in which the memory mechanism includes a fast memory mechanism accessible by the router.

29. The system of claim 26 in which the multiple ports comprise virtual ports.

30. An apparatus for providing flow control comprising:

a receiver processor configured to receive separate indications of an availability of each one of multiple ports not directly connected to the apparatus to accept data from the apparatus;

a transmitter processor configured to control transmission of data from the apparatus to the multiple ports based at least on the indication;

a memory mechanism accessible to the receiver processor and to the transmitter processor and configured to store the indication; and

a bus capable of carrying information between the receiver processor and the transmitter processor.

31. The apparatus of claim 30 in which the transmitter processor is also configured to retrieve information about the indication from the memory mechanism and to use the information in controlling transmission of data from the apparatus to multiple ports.

32. The apparatus of claim 30 in which the memory mechanism includes static random access memory.

33. The apparatus of claim 30 in which the receiver processor is also configured to receive multiple indicators, each of the multiple indicators indicating the availability of a subset of the multiple ports to accept data from the apparatus, and to assemble the multiple indicators to form the indication.

34. The apparatus of claim 30 in which the bus includes a high bandwidth bus internal to the apparatus.

35. The apparatus of claim 30 in which the receiver processor is also configured to receive a packet and the transmitter processor is also configured to determine which one of the multiple ports to transmit the packet to based at least on the indication.

36. The apparatus of claim 30 further comprising a microengine configured to execute program threads, the threads implementing the receiver processor and the transmitter processor.

37. The apparatus of claim 30 in which the multiple ports comprise virtual ports.

38. An apparatus comprising:

a receiver processor configured to receive multiple indicators and to assemble the multiple indicators to form an indication of an availability of each one of multiple ports to accept data from the apparatus, wherein

each of the multiple indicators indicates the availability of a subset of the multiple ports to accept data from the apparatus, and

each of the multiple ports is not directly connected to the apparatus.

39. The apparatus of claim 38 in which the multiple ports comprise virtual ports.

40. An apparatus comprising:

a transmitter processor configured to

control transmission of data from the apparatus to each one of multiple ports based at least on separate indications of an availability of each one of the multiple ports to accept data from the apparatus,

retrieve information about the indication from a memory mechanism, and

use the information in controlling transmission of data from the apparatus to the multiple ports,

wherein the multiple ports are not directly connected to the apparatus.

41. The apparatus of claim 40 in which the multiple ports comprise virtual ports.

42. A method for providing flow control comprising:

receiving, at a router on a sideband bus from a device having access to the multiple ports, separate indications of an availability of each one of multiple ports not directly connected to the router to receive data from the router; and

controlling transmission of data from the router to the multiple ports based at least on the indication.

43. The method of claim 42 in which the multiple ports comprise virtual ports.

44. A method for providing flow control comprising:

receiving at a router a first indication of an availability of each one of a first collection of multiple ports that are not directly connected to the router to receive data from the router;

receiving at the router a second indication of an availability of each one of a second collection of multiple ports that are not directly connected to the router to receive data from the router;

storing the first indication and the second indication at contiguous storage location addresses; and

controlling transmission of data from the router to the first collection of multiple ports based at least on the first indication and to the second collection of multiple ports based at least on the second indication.

45. The method of claim 44 in which the multiple ports comprise virtual ports.

46. An article for providing flow control, the article including a machine-readable medium having machine-executable instructions, the instructions when executed by a machine causing the machine to perform operations comprising:

receiving at a router multiple vectors each indicating an availability of a different collection of multiple ports not directly connected to the router to receive data from the router;

assembling the multiple vectors into a composite; and

controlling transmission of data from the router to the multiple ports based at least on the composite.

47. The article of claim 46 in which the multiple ports comprise virtual ports.

48. An apparatus for providing flow control comprising:

a receiver processor configured to receive a data packet and separate indicators of an availability of each one of multiple ports not directly connected to the apparatus to accept data from the apparatus;

a transmitter processor configured to determine which one of the multiple ports to transmit the packet to based at least on the indication; and

a bus capable of carrying information between the receiver processor and the transmitter processor.

49. The apparatus of claim 48 in which the multiple ports comprise virtual ports.

50. An apparatus for providing flow control comprising:

a microengine configured to execute program threads, the threads implementing a receiver processor and a transmitter processor, wherein the receiver processor is configured to receive separate indications of an availability of each one of multiple ports not directly connected to the apparatus to accept data from the apparatus and the transmitter processor is configured to control transmission of data from the apparatus to the multiple ports based at least on the indication.

51. The apparatus of claim 50 in which the multiple ports comprise virtual ports.

52. An apparatus for providing flow control comprising:

a collection of bi-directional virtual ports;

a router comprising

a receive processor comprising one or more inputs to receive data packets and control message packets,

a transmit processor configured to handle packet transmission over a physical output port based at least in part on an availability of each of the bi-directional virtual ports to receive data from the router, and

a memory accessible to the receive processor and to the transmit processor and configured to store one or more indications of the availability of each of the bi-directional virtual ports; and

an access multiplexer configured to receive packets transmitted by the transmit processor over the physical output port and to convey, to the receive processor in a control message packet, one or more indications of the availability of the bi-directional virtual ports in the collection,

wherein the router is not directly connected to the collection of the bi-directional virtual ports.