VLAN support of differentiated services

• US 20060002370A1
• Filed: 06/30/2005
• Published: 01/05/2006
• Est. Priority Date: 07/02/2004
• Status: Active Grant

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Mohan, Dinesh, Rabie, Sameh, Aboul-Magd, Osama
• Granted Patent: US 8,422,500 B2
• Time in Patent Office: Days
• US Class Current: 370/351
• CPC Class Codes: H04L 12/4645 Details on frame tagging routing of packets H04L45/00; support for virtual LAN H04L49/354
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/30 Routing of multiclass traffic
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2408 for supporting different services, e.g. a differentiated services [DiffServ] type of service
• CPC Class Codes: H04L 47/2433 Allocation of priorities to traffic types
• CPC Class Codes: H04L 47/2491 Mapping quality of service [QoS] requirements between different networks
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames

Abstract

The two types of virtual local area networks (VLANs) may be defined: p-bits-Inferred-scheduling class VLAN (p-VLAN); and VLAN-ID-Only-Inferred-scheduling class VLANs (v-VLAN). As such, upon receipt of an Ethernet frame, the type of VLAN associated with the Ethernet frame may be determined. The type of VLAN provides the receiving node with an indication of a method of determining a scheduling class. A p-VLAN supports multiple scheduling classes. For a p-VLAN, the scheduling class and drop precedence for the received Ethernet frame may be determined based on a “service map” that describes the relationship between the p-bits and forwarding treatment. A v-VLAN supports a single scheduling class. As such, the scheduling class for a received Ethernet frame may be determined based on the VLAN-ID of the received Ethernet frame. The described VLAN QoS information may be configured or signaled across the network. Advantageously, the methods may be applied in connectionless, connection-oriented and path-oriented Ethernet networks.

Claims

1. A method of preparing a network node for forwarding data frames related to a virtual local area network, said method comprising:

defining a service map to include an association between;

contents of a user priority field in said header of said data frame; and

a frame per hop behavior; and

associating said service map with a particular virtual local area network identification.

2. The method of claim 1 wherein said frame per hop behavior has been predefined to be associated with a frame scheduling class.

3. The method of claim 1 wherein said frame per hop behavior has been predefined to be associated with a frame drop precedence.

4. The method of claim 1 wherein said frame per hop behavior is defined based on a per hop behavior selected from a group of standard Internet Protocol Differentiated Services Per Hop Behaviors consisting of:

Expedited Forwarding;

Assured Forwarding;

Class Selector; and

Best Effort.

5. The method of claim 1 further comprising configuring said network node with said service map.

6. The method of claim 1 further comprising signaling said network node with said service map.

7. The method of claim 1 wherein said defining said service map comprises associating said service map with a plurality of virtual local area network identifications.

8. The method of claim 1 wherein said defining said service map comprises associating said service map with a particular network node.

9. The method of claim 1 wherein said defining said service map comprises associating said service map with a particular network segment.

10. The method of claim 1 wherein said defining said service map comprises associating said service map with a particular network.

11. The method of claim 1 wherein said defining said service map comprises associating said service map with a particular interface.

12. The method of claim 1 further comprising:

defining a bandwidth profile; and

associating said bandwidth profile with said particular virtual local area network identification.

13. A method of handling a received data frame, said method comprising:

determining a value for contents of a virtual local area network identification field in a header of said data frame, where said contents of said virtual local area network identification field identify a given virtual local area network;

based on said value for said contents of said virtual local area network identification field, selecting a previously defined service map, where said service map includes an association between;

contents of a user priority field in said header of said data frame; and

a frame per hop behavior; and

determining a value for contents of said user priority field in said header of said data frame;

determining, based on a mapping in said service map to said value for said contents of said user priority field, a given frame per hop behavior for said data frame; and

forwarding said data frame based on said given frame per hop behavior.

14. The method of claim 13 wherein said data frame is an Ethernet frame.

15. The method of claim 14 wherein said header of said Ethernet frame includes an IEEE 802.1Q tag.

16. The method of claim 15 wherein said IEEE 802.1Q tag includes said virtual local area network identification field and said user priority field.

17. The method of claim 13 wherein said given virtual local area network is connectionless.

18. The method of claim 13 wherein said given virtual local area network is connection-oriented.

19. The method of claim 13 wherein said given virtual local area network is path-oriented.

20. A network connected apparatus adapted to:

determine a value for contents of a virtual local area network identification field in a header of said data frame, where said contents of said virtual local area network identification field identify a given virtual local area network;

select, based on said value for said contents of said virtual local area network identification field, a previously defined service map, where said service map includes an association between;

contents of a user priority field in said header of said data frame; and

a frame per hop behavior; and

determine a value for contents of said user priority field in said header of said data frame;

determine, based on a mapping in said service map to said value for said contents of said user priority field, a given frame per hop behavior for said data frame; and

forward said data frame based on said given frame per hop behavior.