Method for providing scalable multicast service in a virtual private LAN service

• US 8,051,201 B2
• Filed: 02/19/2010
• Issued: 11/01/2011
• Est. Priority Date: 08/01/2003
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Foundry Networks LLC (Broadcom, Inc.)
• Inventors: Hsu, Ivy Pei-Shan, Yun, Louis, Jalan, Rajkumar
• Primary Examiner(s): LIN, WEN TAI
• Application Number:
  US12/709,338
• Publication Number:
  US 20100220723A1
• Time in Patent Office: 620 Days
• Field of Search: None
• US Class Current: 709/238
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 49/354 for supporting virtual local area networks [VLAN]
• CPC Class Codes: H04L 63/0272 Virtual private networks

Abstract

Multicast capability in a virtual private LAN service (VPLS) is provided in a provider IP/MPLS infrastructure without headend replications by encapsulating a customer data packet to use an established multicast protocol, such as IP multicast. In one example, the customer data packet is encapsulated by an IP header having an IP multicast group address and an Ethernet header. In one implementation, a DNS type mechanism is provided to distribute the IP multicast addresses for VPLS use. Such IP multicast group address can be set aside from an administratively scoped address range. An efficient IP routing algorithm running on the provider'"'"'s network provides an efficient distribution tree for routing IP-encapsulated customer packet for the VPLS.

Claims

1. A network device comprising:

a processor configured to;

register the network device with a name server by providing an identity or character string representing a virtual private LAN service (VPLS) of which the network device is a member;

periodically access the name server to obtain a list of peer devices in the VPLS;

access the name server to determine an IP multicast group address associated with the VPLS;

encapsulate a data packet of the VPLS in an Internet Protocol (IP) packet designating the IP multicast group address; and

transmit the IP packet using an IP multicast routing protocol.

2. The network device of claim 1 wherein the data packet is an Ethernet multicast packet.

3. The network device of claim 1 wherein the data packet is an Ethernet unicast packet including a destination MAC address.

4. The network device of claim 3 wherein the destination MAC address is unknown to the network device.

5. The network device of claim 1 wherein the IP packet includes an Ethernet header that includes a multicast Ethernet destination address associated with the IP multicast group address.

6. The network device of claim 1 wherein the IP multicast routing protocol is a source-based tree protocol or a core-based tree protocol.

7. The network device of claim 1 wherein the VPLS is part of a Layer 2 virtual private network.

8. The network device of claim 1 wherein the IP multicast group address is selected from a private multicast domain, and wherein a portion of the private multicast domain is reserved for VPLS multicast use and a portion is reserved for native IP multicast use.

9. A network device comprising:

a processor configured to;

register the network device with a name server by providing an identity or character string representing a virtual private LAN service (VPLS) of which the network device is a member;

periodically access the name server to obtain a list of peer devices in the VPLS;

access the name server to determine whether an IP multicast group address associated with a received IP packet corresponds to the VPLS;

de-encapsulate the IP packet to recover a data packet; and

transmit the data packet to one or more devices of the VPLS.

10. The network device of claim 9 wherein the processor is further configured to perform a lookup to determine whether the IP packet should be forwarded to zero or more other network devices in a multicast distribution tree.

11. The network device of claim 9 wherein the data packet is an Ethernet multicast packet.

12. The network device of claim 9 wherein the data packet is an Ethernet unicast packet.

13. The network device of claim 9 wherein the IP packet includes an IP header specifying the IP multicast group address as a destination address.

14. The network device of claim 13 wherein the IP packet further includes an Ethernet header specifying a multicast Ethernet destination address associated with the IP multicast group address.

15. The network device of claim 14 wherein de-encapsulating the IP packet comprises stripping the IP packet of the IP header and the Ethernet header.

16. A method comprising:

registering, by a network device, with a name server, the registering being performed by providing an identity or character string representing a virtual private LAN service (VPLS) of which the network device is a member;

periodically accessing, by the network device, the name server to obtain a list of peer devices in the VPLS;

accessing, by the network device, the name server to determine an IP multicast group address associated with the VPLS;

encapsulating, by the network device, a data packet of the VPLS in an Internet Protocol (IP) packet designating the IP multicast group address; and

transmitting, by the network device, the IP packet using an IP multicast routing protocol.

17. A method comprising:

registering, by a network device, with a name server, the registering being performed by providing an identity or character string representing a virtual private LAN service (VPLS) of which the network device is a member;

periodically accessing, by the network device, the name server to obtain a list of peer devices in the VPLS;

accessing, by the network device, the name server to determine whether an IP multicast group address associated with a received IP packet corresponds to the VPLS;

de-encapsulating, by the network device, the IP packet to recover a data packet; and

transmitting, by the network device, the data packet to one or more devices of the VPLS.

18. A non-transitory machine-readable storage medium having stored thereon program code executable by a processor of a network device, the program code comprising:

code that causes the processor to register the network device with a name server by providing an identity or character string representing a virtual private LAN service (VPLS) of which the network device is a member;

code that causes the processor to periodically access the name server to obtain a list of peer devices in the VPLS;

code that causes the processor to access the name server to determine an IP multicast group address associated with the VPLS;

code that causes the processor to encapsulate a data packet of the VPLS in an Internet Protocol (IP) packet designating the IP multicast group address; and

code that causes the processor to transmit the IP packet using an IP multicast routing protocol.

19. A non-transitory machine-readable storage medium having stored thereon program code executable by a processor of a network device, the program code comprising:

code that causes the processor to register the network device with a name server by providing an identity or character string representing a virtual private LAN service (VPLS) of which the network device is a member;

code that causes the processor to periodically access the name server to obtain a list of peer devices in the VPLS;

code that causes the processor to access the name server to determine whether an IP multicast group address associated with a received IP packet corresponds to the VPLS;

code that causes the processor to de-encapsulate the IP packet to recover a data packet; and

code that causes the processor to transmit the data packet to one or more devices of the VPLS.