Method and system for increasing available user VLAN space

• US 20050138149A1
• Filed: 12/23/2003
• Published: 06/23/2005
• Est. Priority Date: 12/23/2003
• Status: Abandoned Application

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Bhatia, Jagjeet
• Application Number:
  US10/745,713
• Publication Number:
  US 20050138149A1
• Time in Patent Office: Days
• US Class Current: 709/220
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04L 12/465 wherein a single frame includes a plurality of VLAN tags
• CPC Class Codes: H04L 63/0272 Virtual private networks

Abstract

A method and system for conserving VLAN identifier (VID) space in a metropolitan area network (MAN) that transmits data between a plurality of network sites for a plurality of customers, one or more of the customers using tagging to construct a plurality of VLANs. In the preferred embodiment, a first MAN switch marks each customer'"'"'s untagged traffic with a VLAN identifier conserving (VIC) tag prior to transmitting the traffic through the MAN. The VIC tag, preferably an 802.1Q tag includes a dedicated Ethertype, i.e., a VLAN protocol identifier (VPID), different than the VPID the 0×8110 used with the customers'"'"' VLAN tagged traffic or with the metro tag used to tunnel the customers'"'"' traffic through the MAN. The VIC obviates the need to assign a VID for each customer'"'"'s untagged traffic that propagates through the MAN, thereby making a plurality of VID available for customers.

Claims

1. A method for increasing a user virtual local area network (VLAN) space in a system adapted to transmit protocol data units (PDUs) received from at least a first network and a second network over shared communications links, wherein the first network comprises a first untagged domain and a first VLAN domain associated with a first VLAN identifier (VID) space, and the second network comprises a second untagged domain, the method comprising the steps of:

tagging one or more PDUs from the first untagged domain with a VLAN identifier conservation (VIC) tag comprising a VLAN identifier associated with the first network; and

tagging one or more PDUs from the second untagged domain with a VLAN identifier conservation (VIC) tag comprising a VLAN identifier associated with the second network.

2. The method of claim 1, wherein the VIC tag used for the first untagged domain and the second untagged domain further comprise a VLAN protocol identifier (VPID).

3. The method of claim 2, wherein one or more PDUs from the first VLAN comprises a VLAN tag comprising a VPID and a VID selected from the first VLAN space, and wherein the VPID of the VIC tag is different than the VPID of the VLAN tag.

4. The method of claim 3, wherein the VLAN tag and the VIC tag are 802.1Q tags.

5. The method of claim 4, wherein the VPID of the VLAN tag has a value of 0×

8100.

6. The method of claim 5, wherein the PDUs comprising either the VLAN tag or the VIC tag further comprise an outer VLAN tag to tunnel the PDUs over the shared communications links.

7. The method of claim 1, in a first metropolitan area network (MAN) switch, wherein the first network is associated with a first customer network and the second network is associated with a second customer network.

8. The method of claim 7, wherein the VLAN identifier associated with the first customer network is a first customer identifier and the VLAN identifier associated with the second customer network is a second customer identifier.

9. The method of claim 7, wherein the second network comprises a second VLAN domain associated with a second VID space different than the first VID space.

10. The method of claim 9, wherein substantially all the PDUs from the first network and substantially all the PDUs from the second network are further tagged with a metro tag through a MAN.

11. The method of claim 10, wherein the metro tag is an outer tag with respect to a VIC tag.

12. The method of claim 10, in a second MAN switch, wherein the method further comprises the steps of:

receiving one or more PDUs with a metro tag and a VIC tag;

removing the metro tag and the VIC tag; and

transmitting untagged PDUs within the associated customer network.

13. A method for preserving a logical group association of packets transmitted over a communication network having multiple logical groups, comprising the steps of:

determining a VLAN tag state of a packet; and

applying a VLAN tag to the packet in response to the determination,

wherein the VLAN tag includes a VLAN protocol identifier reserved for untagged packets.

14. The method of claim 13, wherein the VLAN tag further includes an identifier of a logical group to which the packet belongs.

15. The method of claim 14, further comprising the steps of:

reviewing the VLAN tag; and

forwarding the packet on a port associated with the logical group in response to the review.

16. A method for transmitting a plurality of PDUs through a network, wherein the plurality of PDUs comprises a first group of one or more PDUs associated with an untagged domain, the method comprising the steps of:

applying to the PDUs of the first group entering the network a first VLAN tag comprising a first VLAN protocol identifier (VPID) reserved for untagged PDUs; and

applying to the PDUs of the first group with the first VLAN tag a second VLAN tag comprising a second VPID;

wherein the first VPDI and second VPID are different.

17. The method in claim 16, wherein the plurality of PDUs further comprises a second group of one or more PDUs associated with one or more VLAN domains;

and wherein the method further comprises the step of applying to the PDUs of the second group entering the network a third VLAN tag, wherein the first VLAN tag and second VLAN tag are substantially the same.

18. The method in claim 16, wherein the second VLAN tag is an 802.1Q tag and the second VPID has a value of 0×

8100.

19. The method in claim 16, wherein the method further comprises the step of removing from the PDUs of the first group exiting the network both the first VLAN tag and the second VLAN tag.

20. The method in claim 16, wherein the network is a metropolitan area network.