Monitoring a flow set to detect faults

• US 8,588,081 B2
• Filed: 07/14/2010
• Issued: 11/19/2013
• Est. Priority Date: 07/14/2010
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Salam, Samer, Sajassi, Ali
• Primary Examiner(s): ABELSON, RONALD B
• Application Number:
  US12/835,777
• Publication Number:
  US 20120014261A1
• Time in Patent Office: 1,224 Days
• Field of Search: 370/242, 370/248, 370/249
• US Class Current: 370/242
• CPC Class Codes: H04L 43/026 using flow identification
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route

Abstract

In certain embodiments, monitoring a flow set to detect faults includes identifying, by a first maintenance end point, a flow set comprising flows that utilize a paths from the first maintenance end point through one or more intermediate nodes to a second maintenance end point. Continuity check messages are generated. Each continuity check message is formatted as a data packet that an intermediate node forwards. Each continuity check message comprises a header comprising a maintenance indicator. The continuity check messages are transmitted on the flows to allow the second maintenance end point to monitor the paths.

Claims

1. A method comprising:

identifying, by a first maintenance end point, a flow set comprising a plurality of flows that utilize a plurality of paths from the first maintenance end point through one or more intermediate nodes to a second maintenance end point;

generating a plurality of continuity check messages, each continuity check message formatted as a data packet that an intermediate node treats like a data packet instead of a maintenance packet, each continuity check message comprising a Transparent Interconnection of Lots of Links (TRILL) header comprising a maintenance indicator; and

transmitting the continuity check messages on the flows to allow the second maintenance end point to monitor the paths, the one or more second maintenance end points comprising one or more receiving endpoints configured to determine an expected number of the plurality of flows utilizing the plurality of paths and to detect a flow problem based on the expected number of the plurality of flows to be received on the plurality of paths and the continuity check messages received.

2. The method of claim 1, the header comprising an inner Ethernet header disposed after the TRILL header and an outer Ethernet header disposed before the TRILL header.

3. The method of claim 1, the identifying a flow set further comprising:

determining the flows from a hashing algorithm and the paths.

4. The method of claim 1, the identifying a flow set further comprising:

performing a path finding technique operating at the Ethernet layer to yield the flows.

5. The method of claim 1, the identifying a flow set further comprising:

determining the flows from information configured at the first maintenance end point.

6. The method of claim 1, the transmitting the continuity check messages further comprising:

transmitting the continuity check messages according to a round robin scheduling scheme.

7. The method of claim 1, the transmitting the continuity cheek messages further comprising:

transmitting a first subset of the continuity check messages at a first rate along a first subset of the flows; and

transmitting a second subset of the continuity check messages at a second rate along a second subset of the flows, the first rate higher than the second rate, the first subset of flows more critical than the second subset of flows.

8. An apparatus comprising:

one or more non-transitory computer readable media configured to store computer executable instructions; and

one or more processors of a first maintenance end point, the processors configured, when executing the instructions, to;

identify a flow set comprising a plurality of flows that utilize a plurality of paths from the first maintenance end point through one or more intermediate nodes to a second maintenance end point;

generate a plurality of continuity check messages, each continuity check message formatted as a data packet that an intermediate node treats like a data packet instead of a maintenance packet, each continuity check message comprising a Transparent Interconnection of Lots of Links (TRILL) header comprising a maintenance indicator; and

transmit the continuity check messages on the flows to allow the second maintenance end point to monitor the paths, the one or more second maintenance end points comprising one or more receiving endpoints configured to determine an expected number of the plurality of flows utilizing the plurality of paths and to detect a flow problem based on the expected number of the plurality of flows to be received on the plurality of paths and the continuity check messages received.

9. The apparatus of claim 8, the header comprising an inner Ethernet header disposed after the TRILL, header and an outer Ethernet header disposed before the TRILL header.

10. The apparatus of claim 8, the identifying a flow set further comprising:

determining the flows from a hashing algorithm and the paths.

11. The apparatus of claim 8, the identifying a flow set further comprising:

performing a path finding technique operating at the Ethernet layer to yield the flows.

12. The apparatus of claim 8, the identifying a flow set further comprising:

determining the flows from information configured at the first maintenance end point.

13. The apparatus of claim 8, the transmitting the continuity check messages further comprising:

transmitting the continuity check messages according to a round robin scheduling scheme.

14. The apparatus of claim 8, the transmitting the continuity check messages further comprising:

transmitting a first subset of the continuity check messages at a first rate along a first subset of the flows; and

transmitting a second subset of the continuity check messages at a second rate along a second subset of the flows, the first rate higher than the second rate, the first subset of flows more critical than the second subset of flows.

15. One or more non-transitory computer readable media configured to store computer executable instructions that, when executed by one or more processors, are configured to:

identify a flow set comprising a plurality of flows that utilize a plurality of paths from the first maintenance end point through one or more intermediate nodes to a second maintenance end point;

generate a plurality of continuity check messages, each continuity check message formatted as a data packet that an intermediate node treats like a data packet instead of a maintenance packet, each continuity check message comprising a Transparent Interconnection of Lots of Links (TRILL) header comprising a maintenance indicator; and

transmit the continuity check messages on the flows to allow the second maintenance end point to monitor the paths, the one or more second maintenance end points comprising one or more receiving endpoints configured to determine an expected number of the plurality of flows utilizing the plurality of paths and to detect a flow problem based on the expected number of the plurality of flows to be received on the plurality of paths and the continuity check messages received.

16. The media of claim 15, the header comprising an inner Ethernet header disposed after the TRILL header and an outer Ethernet header disposed before the TRILL header.

17. The media of claim 15, the transmitting the continuity check messages further comprising:

transmitting the continuity check messages according to a round robin scheduling scheme.