Supporting multiple application traffic types over connection oriented networks

• US 6,430,154 B1
• Filed: 08/10/2000
• Issued: 08/06/2002
• Est. Priority Date: 08/13/1999
• Status: Expired due to Fees

• Current Assignee: Fujitsu Network Communications Incorporated (Fujitsu Limited)
• Original Assignee: Fujitsu Network Communications Incorporated (Fujitsu Limited)
• Inventors: Northcote, Bruce S., Hunt, Douglas H.
• Primary Examiner(s): Nguyen, Chau
• Assistant Examiner(s): TRINH, DUNG N
• Application Number:
  US09/636,479
• Time in Patent Office: 726 Days
• Field of Search: 370/230, 370/395, 370/397, 370/399, 370/409, 370/410, 370/437, 370/468, 370/230.1, 370/236.2, 370/241.1, 370/395.1, 370/395.2, 370/395.21, 370/395.3, 370/395.43
• US Class Current: 370/230.1
• CPC Class Codes: H04L 2012/561 Star, e.g. cross-connect, concentrator, subscriber group equipment, remote electronics
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 2012/5679 Arbitration or scheduling
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2416 Real-time traffic
• 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 47/245 using preemption
• CPC Class Codes: H04L 47/50 Queue scheduling
• CPC Class Codes: H04L 47/521 Static queue service slot or fixed bandwidth allocation
• CPC Class Codes: H04L 47/60 implementing hierarchical scheduling
• CPC Class Codes: H04L 47/621 Individual queue per connection or flow, e.g. per VC
• CPC Class Codes: H04L 47/6225 Fixed service order, e.g. Round Robin
• CPC Class Codes: H04L 47/623 Weighted service order
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/168 specially adapted for link layer protocols, e.g. asynchronous transfer mode [ATM], synchronous optical network [SONET] or point-to-point protocol [PPP]
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

A system and a method are disclosed for supporting multiple application traffic types over connection oriented networks. Data is received from multiple applications, for example in the form of data units, and is associated with a traffic type. The traffic type associated with a data unit indicates whether the data unit is inelastic traffic or elastic traffic. Data associated with inelastic traffic is mapped to at least one connection of a first connection type which provides for some amount of committed bandwidth, and limits on delay variation. Data associated with elastic traffic is mapped to at least one connection of a second connection type, which does not provide any committed bandwidth. Connections of the second connection type may ensure that elastic traffic data units that are accepted for transfer by the underlying network are delivered without loss due to network congestion, for example, by use of a flow control technique. A hierarchical scheduler may be employed to schedule transmissions of data units across connections organized into virtual trunks. The hierarchical scheduler may be used to ensure a high multiplexing gain with respect to connections within a single virtual trunk, as well as across multiple virtual trunks.

Claims

1. A method for passing information over a connection oriented network, comprising:

receiving data, said data including inelastic traffic and elastic traffic;

identifying said inelastic traffic and said elastic traffic within said data;

associating said inelastic traffic with at least one virtual connection of a first connection type, wherein said at least one virtual connection of said first connection type provides a predetermined amount of committed bandwidth;

associating said elastic traffic with at least one virtual connection of a second connection type, wherein said at least one virtual connection of said second connection type does not provide committed bandwidth;

wherein said step of receiving data further comprises receiving a plurality of data units, and wherein said inelastic traffic includes at least one inelastic traffic data unit, and wherein said elastic traffic includes at least one elastic traffic data unit;

wherein each of said plurality of data units includes an indication of a traffic type, wherein said traffic type is equal to one of the set consisting of inelastic traffic and elastic traffic, and wherein said step of identifying said inelastic traffic and said elastic traffic further comprises examining said indication of said traffic type within each of said plurality of data units; and

wherein said indication of said traffic type within each of said plurality of data units comprises a differentiated services field within an Internet Protocol (IP) header of each of said plurality of data units, and wherein said step of identifying said inelastic traffic and said elastic traffic further comprises examining said differentiated services field.

2. The method of claim 1, wherein said step of identifying said inelastic traffic and said elastic traffic further comprises examining a differentiated services code point within said differentiated services field in order to determine a per hop behavior.

3. The method of claim 2, wherein said per hop behavior consists of one of the group consisting of expedited forwarding and assured forwarding.

4. The method of claim 3, wherein said step of identifying said inelastic traffic and said elastic traffic further comprises identifying a first one of said plurality of data units as inelastic traffic in the event that said differentiated services code point of said first one of said plurality of data units indicates said expedited forwarding per hop behavior.

5. The method of claim 4, wherein said step of identifying said inelastic traffic and said elastic traffic further comprises identifying a second one of said plurality of data units as elastic traffic in the event that said differentiated services code point of said second one of said plurality of data units indicates said assured forwarding per hop behavior.

6. The method of claim 1, further comprising:

wherein said step of associating said inelastic traffic with said at least one virtual connection of said first connection type includes associating said data units of said inelastic traffic type with said at least one virtual connection of said first connection type; and

wherein said step of associating said elastic traffic with said at least one virtual connection of said second connection type includes associating said data units of said elastic traffic type with said at least one virtual connection of said second connection type.

7. The method of claim 1, further comprising providing said committed bandwidth for said at least one virtual connection of said first connection type without loss of data transmitted over said at least one virtual connection of said first connection type in the event that an amount of said inelastic data does not exceed a predetermined maximum data rate associated with said at least one virtual connection of said first connection type.

8. The method of claim 1, further comprising providing said committed bandwidth for said at least one virtual connection of said first connection type with a maximum delay variation for data units transmitted over said at least one virtual connection of said first connection type.

9. The method of claim 1, further comprising providing a flow control mechanism for said elastic traffic associated with said at least one virtual connection of said second connection type.

10. The method of claim 9, further comprising providing a service with no loss due to network congestion for said elastic traffic associated with said at least one virtual connection of said second connection type in the event that said elastic traffic is accepted for transmission.

11. The method of claim 1, further comprising establishing at least one constant bit rate (CBR) virtual connection as said at least one virtual connection of said first connection type.

12. The method of claim 1, further comprising establishing at least one unspecified bit rate (UBR) connection as said at least one virtual connection of said second connection type.

13. The method of claim 1, further comprising establishing at least one Controlled Transfer (CT) connection as said at least one virtual connection of said second connection type.

14. The method of claim 1, further comprising allocating transmission opportunities based on a hierarchical scheduler such that unused transmission opportunities associated with said at least one virtual connection of said first connection type are allocated to said at least one virtual connection of said second connection type.

15. The method of claim 14, further comprising associating said at least one virtual connection of said first connection type and said at least one virtual connection of said second connection type with a first virtual trunk, and wherein said allocating transmission opportunities based on said hierarchical scheduler further comprises allocating said unused transmission opportunities associated with said at least one virtual connection of said first connection type to a virtual connection associated with a second virtual trunk in the event that no data associated with said at least one connection of said second connection type is available for transmission.

16. A system for passing information over a connection oriented network, comprising:

at least one processor;

a memory coupled to said processor;

a traffic mapping controller, wherein said controller operates to

receive data, said data including inelastic traffic and elastic traffic,

identify said inelastic traffic and said elastic traffic within said data,

associate said inelastic traffic with at least one virtual connection of a first connection type, wherein said at least one virtual connection of said first connection type provides a predetermined amount of committed bandwidth, and associate said elastic traffic with at least one virtual connection of a second connection type, wherein said at least one virtual connection of said second connection type does not provide committed bandwidth;

wherein said traffic mapping controller further operates to receive a plurality of data units as said data, wherein said inelastic traffic includes at least one inelastic traffic data unit, and wherein said elastic traffic includes at least one elastic traffic data unit;

wherein each of said plurality of data units includes an indication of a traffic type, wherein said traffic type is equal to one of the set consisting of inelastic traffic and elastic traffic, and wherein said traffic mapping controller further operates to identify said inelastic traffic and said elastic traffic by examining said indication of said traffic type within each of said plurality of data units; and

wherein said indication of said traffic type within each of said plurality of data units comprises a differentiated services field within an Internet Protocol (IP) header of each of said plurality of data units, and wherein said traffic mapping controller further operates to identify said inelastic traffic and said elastic traffic further by examining said differentiated services field.

17. The system of claim 16, wherein said traffic mapping controller further operates to identify said inelastic traffic and said elastic traffic further by examining a differentiated services code point within said differentiated services field in order to determine a per hop behavior, wherein said per hop behavior consists of one of the group consisting of expedited forwarding and assured forwarding.

18. The system of claim 17, wherein said traffic mapping controller further operates to identify said inelastic traffic and said elastic traffic further by identifying a first one of said plurality of data units as inelastic traffic in the event that said differentiated services code point of said first one of said plurality of data units indicates said expedited forwarding per hop behavior.

19. The system of claim 18, wherein said traffic mapping controller further operates to identify said inelastic traffic and said elastic traffic by identifying a second one of said plurality of data units as elastic traffic in the event that said differentiated services code point of said second one of said plurality of data units indicates said assured forwarding per hop behavior.

20. The method of claim 16, further comprising:

wherein said traffic mapping controller further operates to associate said inelastic traffic with said at least one virtual connection of said first connection type by associating said data units of said inelastic traffic type with said at least one virtual connection of said first connection type; and

wherein said traffic mapping controller further operates to associate said elastic traffic with said at least one virtual connection of said second connection type by associating said data units of said elastic traffic type with said at least one virtual connection of said second connection type.

21. The system of claim 16, wherein said traffic mapping controller further operates to provide said committed bandwidth for said at least one virtual connection of said first connection type without loss of data transmitted over said at least one virtual connection of said first connection type in the event that an amount of said inelastic data does not exceed a predetermined maximum data rate associated with said at least one virtual connection of said first connection type.

22. The system of claim 16, wherein said traffic mapping controller further operates to provide said committed bandwidth for said at least one virtual connection of said first connection type with a maximum delay variation for data units transmitted over said at least one virtual connection of said first connection type.

23. The system of claim 16, wherein said traffic mapping controller further operates to provide a flow control mechanism for said elastic traffic associated with said at least one virtual connection of said second connection type.

24. The system of claim 23, wherein said traffic mapping controller further operates to provide a guarantee of delivery for said elastic traffic associated with said at least one virtual connection of said second connection type in the event that said elastic traffic is accepted for transmission, without loss due to network congestion.

25. The system of claim 16, wherein said traffic mapping controller further operates to establish at least one constant bit rate (CBR) virtual connection as said at least one virtual connection of said first connection type.

26. The system of claim 16, wherein said traffic mapping controller further operates to establish at least one unspecified bit rate (UBR) connection as said at least one virtual connection of said second connection type.

27. The system of claim 16, wherein said traffic mapping controller further operates to establish at least one Controlled Transfer (CT) connection as said at least one virtual connection of said second connection type.

28. The system of claim 16, wherein said traffic mapping controller further operates to allocate transmission opportunities based on a hierarchical scheduler such that unused transmission opportunities associated with said at least one virtual connection of said first connection type are allocated to said at least one virtual connection of said second connection type.

29. The system of claim 28, wherein said traffic mapping controller further operates to associate said at least one virtual connection of said first connection type and said at least one virtual connection of said second connection type with a first virtual trunk, and wherein said allocating transmission opportunities based on said hierarchical scheduler further comprises allocating said unused transmission opportunities associated with said at least one virtual connection of said first connection type to a virtual connection associated with a second virtual trunk in the event that no data associated with said at least one connection of said second connection type is available for transmission.

30. The system of claim 16, wherein said traffic mapping controller comprises a software program stored within said memory.

31. The system of claim 16, wherein said traffic mapping controller comprises at least one integrated circuit.

32. The system of claim 16, wherein said traffic mapping controller comprises a software program stored within said memory and at least one integrated circuit.

33. The system of claim 16, wherein said system is embodied within an edge device of said connection oriented network.

34. The system of claim 16, wherein said system is embodied within an end station.