System and method for recognizing and assigning application-specific flows

• US 7,934,016 B2
• Filed: 04/09/2007
• Issued: 04/26/2011
• Est. Priority Date: 06/29/2001
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Davie, Bruce S., Oran, David R., DiBiasio, Michael V.
• Primary Examiner(s): EL CHANTI, HUSSEIN A
• Application Number:
  US11/784,748
• Publication Number:
  US 20070192507A1
• Time in Patent Office: 1,478 Days
• Field of Search: 709/224, 709/231, 709/238, 709/240, 709/241
• US Class Current: 709/240
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/215 using token-bucket
• CPC Class Codes: H04L 47/2433 Allocation of priorities to traffic types
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/2475 for supporting traffic characterised by the type of applications
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/724 at intermediate nodes, e.g. resource reservation protocol [RSVP]
• CPC Class Codes: H04L 47/801 Real time traffic

Abstract

In one embodiment, an intermediate network device includes a communication facility configured to receive a reservation request message that includes a flow spec object. The flow spec object specifies one or more flow parameters that describe a given traffic flow that desires to pass through the intermediate network device. A flow is configured to compare the one or more flow parameters specified in the flow spec object to one or more constants stored in a memory, to determine a type of traffic of the given traffic flow. The flow analyzer determines the type of traffic independent of any differentiated services codepoint (DSCP) values in packets of the given traffic flow. A traffic scheduler is configured to assign the given traffic flow to a particular per hop behavior (PHB) based on the determined type of traffic for the given traffic flow.

Claims

1. An apparatus comprising:

a packet/frame receiver transmitter that includes at least one network interface, the packet/frame receiver transmitter configured to receive a reservation request message that includes a flow spec object that specifies one or more flow parameters, the flow parameters to describe a given traffic flow that desires to pass through the apparatus;

a flow analyzer that includes one or more programmable processing elements, the flow analyzer configured to compare the one or more flow parameters specified in the flow spec object to one or more constants stored in a memory of the apparatus and to determine a type of traffic of the given traffic flow, the flow analyzer to determine the type of traffic independent of any differentiated services codepoint (DSCP) values in packets of the given traffic flow; and

the flow analyzer further configured to assign the given traffic flow to a particular per hop behavior (PHB) based on the determined type of traffic for the given traffic flow.

2. The apparatus of claim 1, wherein the reservation request message is a Resource ReSerVation Protocol (RSVP) Reservation (Resv) message that includes the flow spec object.

3. The apparatus of claim 2, further comprising:

a RSVP engine configured to match portions of the RSVP Resv message to one or more entries of a data structure to associated the RSVP Resv message with the given traffic flow.

4. The apparatus of claim 1, wherein the particular PHB assigned by the traffic scheduler to the given traffic flow is Expedited Forwarding (EF) PHB.

5. The apparatus of claim 1, wherein the flow analyzer is further configured to assign the given traffic flow to a particular queue of the apparatus.

6. The apparatus of claim 5, wherein the particular queue is selected based on the particular PHB assigned to the given traffic flow.

7. The apparatus of claim 5, wherein the determined type of traffic of the given traffic flow is real time voice traffic and the particular queue is a priority queue (PQ) that is serviced with preference over one or more other queues.

8. The apparatus of claim 1, wherein the flow analyzer is further configured to assign the given traffic flow to a particular queue servicing algorithm.

9. The apparatus of claim 8, wherein the particular queue servicing algorithm is selected based on the particular PHB assigned to the given traffic flow.

10. The apparatus of claim 8, wherein the particular queue servicing algorithm assigned to the given traffic flow is Weighted Round Robin (WRR).

11. The apparatus of claim 1, wherein the apparatus further comprises:

an admission control entity configured to determine whether a particular queue of the apparatus is available for assignment to the traffic flow; and

a message generator configured to, in response to an indication from the admission control entity that the particular queue is not available, generate an error message indicating that the reservation request has failed.

12. The apparatus of claim 1, wherein the one or more flow parameters of the flow spec object comprise one or more parameters selected from the group consisting of:

a minimum policed unit, a maximum packet size, a token bucket rate, a token bucket size, and a peak data rate.

13. The apparatus of claim 1, wherein the apparatus is an intermediate network device configured to be arranged in a computer network between a first hop network device coupled to a source of the given traffic flow, and another first hop network device coupled to a destination of the given traffic flow.

14. A method comprising:

receiving, by a network interface coupled to a computer network, a reservation request message that includes a flow spec object that specifies one or more flow parameters, the flow parameters describing a given traffic flow;

comparing the one or more flow parameters specified in the flow spec object to one or more constants stored in a memory;

in response to the comparing, determining a type of traffic of the given traffic flow, the determining performed independent of any differentiated services codepoint (DSCP) values in packets of the given traffic flow; and

assigning the given traffic flow to a particular per hop behavior (PHB) based on the determined type of traffic for the given traffic flow.

15. The method of claim 14, wherein the reservation request message is a Resource ReSerVation Protocol (RSVP) Reservation (Resv) message that includes the flow spec object.

16. The method of claim 14, further comprising:

assigning the given traffic flow to a particular queue based on the particular PHB assigned to the given traffic flow.

17. The method of claim 16, wherein the determined type of traffic of the given traffic flow is real time voice traffic and the particular queue is a priority queue (PQ) that is serviced with preference over one or more other queues.

18. The method of claim 14, further comprising:

assigning the given traffic flow to a particular queue servicing algorithm based on the particular PHB assigned to the given traffic flow.

19. The method of claim 14, wherein the method is implemented by an intermediate network device arranged in a computer network between a first hop network device coupled to a source of the given traffic flow, and another first hop network device coupled to a destination of the given traffic flow.

20. An apparatus comprising:

means for receiving a reservation request message that includes a flow spec object that specifies one or more flow parameters, the flow parameters describing a given traffic flow;

means for comparing the one or more flow parameters specified in the flow spec object to one or more constants stored in a memory;

means for determining a type of traffic of the given traffic flow in response to the comparison of the one or more flow parameters to the one or more constants, the means for determining to determine the type of traffic independent of any differentiated services codepoint (DSCP) values in packets of the given traffic flow; and

means for assigning the given traffic flow to a particular per hop behavior (PHB) based on the determined type of traffic for the given traffic flow.

21. The apparatus of claim 20, wherein the reservation request message is a Resource ReSerVation Protocol (RSVP) Reservation (Resv) message that includes the flow spec object in a field following a header of the RSVP Resv message.