Systems and methods for routing data in a network device

• US 7,936,759 B2
• Filed: 12/06/2006
• Issued: 05/03/2011
• Est. Priority Date: 04/12/2002
• Status: Expired due to Fees

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Gaudet, Brian, Kritayakirana, Kong
• Primary Examiner(s): Phan; Man
• Assistant Examiner(s): Mansoury; Nourali
• Application Number:
  US11/567,414
• Publication Number:
  US 20070174728A1
• Time in Patent Office: 1,609 Days
• Field of Search: 370/392, 370/394, 370229-236, 370/389, 370/442, 370/472, 370/473, 370/474, 370/475
• US Class Current: 370/394
• CPC Class Codes: H04J 3/1617 carrying packets or ATM cells
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/0847 Transmission error
• CPC Class Codes: H04L 43/16 Threshold monitoring

Abstract

A system detects an error in a network device that receives data via a group of data streams. The system receives a data unit, where the data unit is associated with at least one of the streams and a sequence number for each of the associated streams. The system determines whether each sequence number associated with the data unit is a next sequence number for the corresponding stream, and detects an error for a particular stream when the sequence number for that stream is not a next sequence number.

Claims

1. A method comprising:

receiving data, where receiving the data comprises receiving a first data unit, the first data unit being associated with at least two streams in a plurality of streams and including a sequence number and a stream identifier for each stream with which the first data unit is associated;

determining, for the each stream with which the first data unit is associated, whether the sequence number is a next sequence number; and

terminating, when the sequence number is not the next sequence number for a first stream of the at least two streams, a second data unit that is associated with the first data unit.

2. The method of claim 1, where the terminating includes:

marking the second data unit with an error.

3. The method of claim 1,

where the second data unit includes a packet, and

where the terminating includes:

marking the packet with an end of packet error.

4. The method of claim 1 further comprising:

retrieving, when a second sequence number, which is associated with a second stream of the at least two streams, is the next sequence number for the second stream of the at least two streams, data associated with a third data unit from the first data unit; and

processing the data.

5. The method of claim 1 further comprising:

determining whether the first data unit is associated with a cyclic redundancy check (CRC) error; and

discarding the first data unit when the first data unit is determined to be associated with the CRC error.

6. The method of claim 1 further comprising:

determining whether the first data unit is associated with a start pulse, and

where the determining whether the sequence number is the next sequence number occurs when the first data unit is determined to be associated with the start pulse.

7. A network device that receives data via a plurality of streams, comprising:

a transmitter to;

transmit data, where transmitting the data comprises transmitting a first data unit that is associated with at least two streams of the plurality of streams and comprising a stream identifier and a sequence number for each stream with which the first data unit is associated; and

a receiver to;

receive the first data unit,

determine whether each of the sequence numbers associated with the first data unit is a next sequence number for a respective stream of the at least two streams, and

terminate, when one sequence number with which the first data unit is associated is not the next sequence number for one stream of the at least two streams, a second data unit that is associated with the first data unit.

8. The network device of claim 7, where, when terminating the second data unit, the receiver is further to:

mark the second data unit with an error.

9. The network device of claim 7, where the second data unit includes a packet, and

where, when terminating the second data unit, the receiver is to:

mark the packet with an end of packet error.

10. The network device of claim 7, where the receiver is further to:

retrieve, when a second sequence number, which is associated with a second stream of the at least two streams, is the next sequence number for the second stream, data associated with a third data unit from the first data unit, and

process the retrieved data.

11. The network device of claim 7, where the receiver is further to:

determine whether the first data unit is associated with a cyclic redundancy check (CRC) error; and

discard the first data unit when the first data unit is determined to be associated with the CRC error.

12. The network device of claim 7, where the receiver is further to:

determine whether the first data unit is associated with a start pulse, and

where the receiver performs the determining whether the sequence number is the next sequence number when the receiver determines that the first data unit is associated with the start pulse.

13. The network device of claim 7, where the network device includes a router.

14. The network device of claim 13, where the transmitter is associated with an interface card and the receiver is associated with a port concentrator.

15. A network device comprising:

a first component to;

receive data, where receiving the data comprises receiving a data unit that is associated with a plurality of streams, the data unit comprising packet data and control information for packets associated with one or more of the plurality of streams, and

transmit portions of the data unit via a plurality of high speed transmitters, where each of the high speed transmitters transmits a respective portion of the data unit in synchronism with the other of the plurality of high speed transmitters; and

a second component that connects to the first component via a plurality of high speed links, the second component being to;

receive the portions of the data unit via a plurality of high speed receivers,

correct an imbalance or delay between the portions of the data unit caused by the high speed links,

reconstruct the packet data and the control information from the corrected portions,

determine, for each stream associated with the data unit, whether a particular portion of the data unit, associated with a particular stream of the plurality of streams, was received in a particular sequence, where the determining is based on a particular control information associated with the particular portion of the data unit and the particular stream, and

terminate the particular portion of the data unit the particular portion of the data unit was not received in the particular sequence.

16. The network device of claim 15, where the first component further comprises:

a first set of aligners to;

receive the portions of the data unit,

align the portions of the data unit from a first data width to a second data width, and

transmit the aligned portions of the data unit to the plurality of high speed transmitters,

where the plurality of high speed transmitters transmit the aligned portions of the data unit via the high speed links.

17. The network device of claim 16, where the second component comprises:

a second set of aligners to;

receive the corrected portions of the data unit, and

realign the corrected portions of the data unit from the second data width back to the first data width.

18. The network device of claim 15 where the second component is further to:

determine whether a predetermined amount of time since last receipt of one of a start pulse or a cyclic redundancy check (CRC) error pulse has been exceeded, and

flush data from each of the plurality of streams when the predetermined amount of time has been exceeded.

19. The network device of claim 18, where, when flushing, the second component is to:

mark the data in each of the plurality of streams as containing an error.

20. The network device of claim 15, where the second component is further to:

determine whether the data unit is associated with a cyclic redundancy check (CRC) error, and

discard the data unit when the data unit is determined to be associated with the CRC error.