METHOD AND APPARATUS FOR PROVIDING FAST REROUTE OF A MULTICAST PACKET WITHIN A NETWORK ELEMENT TO AN AVAILABLE PORT ASSOCIATED WITH A MULTI-LINK TRUNK

• US 20100290464A1
• Filed: 05/03/2010
• Published: 11/18/2010
• Est. Priority Date: 05/13/2009
• Status: Active Grant

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Incorporated
• Inventors: Assarpour, Hamid
• Granted Patent: US 8,351,431 B2
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/557 Error correction, e.g. fault recovery or fault tolerance
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A method, apparatus and computer program product for providing a fast re-route of a multicast packet within a network element to an available port associated with a multi-link trunk is presented. A packet is received by a Forwarding Data Unit (FDU) in a data plane of a network element and a determination made that the packet is a multicast packet. The packet is forwarded to all egress FDUs having at least one port associated with at least one receiver of the multicast packet. A lookup is performed by each egress FDU in a synchronized local port state database to find a port for each receiver that is in an UP state. The packet is forwarded out the port to a receiver when the port is in the UP state and dropped when the port is in the DOWN state.

Claims

1. A computer-implemented method in which a Forwarding Data Unit (FDU) performs operations providing a fast re-route of a multicast packet within a network element to an available port associated with a multi-link trunk, the method comprising the steps of:

receiving a packet by said FDU in a data plane of a network element;

determining that the packet is a multicast packet;

forwarding the packet to all egress FDUs having at least one port associated with at least one receiver of the multicast packet; and

performing a lookup by each egress FDU in a synchronized local port state database to find a port for each receiver that is in an UP state.

2. The method of claim 1 wherein said forwarding the packet to all egress FDUs having at least one port associated with at least one receiver of the multicast packet further comprises:

determining if a receiver port is one of the group consisting of a stand alone port, an MLT group for a local FDU, and a MLT group for a remote FDU; and

forwarding a copy to each MLT member.

3. The method of claim 2 wherein when said receiver port is a stand alone port then determining whether said standalone port is in an UP state or a DOWN state, forwarding said packet out said port to a receiver when said port is in the UP state and dropping said packet when said port is in the DOWN state.

4. The method of claim 2 wherein when said receiver port is an MLT group for a local FDU then locating a local port member from the local port state table that is in an UP state.

5. The method of claim 4 further comprising forwarding said packet out said port that is in an UP state and dropping said packet by all remote FDUs.

6. The method of claim 4 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said local port state database.

7. The method of claim 2 wherein when said receiver port is an MLT group for a remote FDU then checking remote port tables to determine whether any MLT ports on originating network element are in the UP state.

8. The method of claim 7 further comprising when one MLT port on the originating network element are in the UP state then dropping said packet by said remote FDUs.

9. The method of claim 7 further comprising when all MLT ports on the originating node are down then selecting one remote port to transmit said packet and dropping said packet by all other remote ports.

10. The method of claim 7 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said remote port state database.

11. A Forwarding Data Unit (FDU) comprising:

a memory;

a processor;

a communications interface;

an interconnection mechanism coupling the memory, the processor and the communications interface; and

wherein the memory is encoded with an application providing a fast re-route of a multicast packet within a network element to an available port associated with a multi-link trunk, that when performed on the processor, provides a process for processing information, the process causing the FDU to perform the operations of;

receiving a packet by said FDU in a data plane of a network element;

determining that the packet is a multicast packet;

forwarding the packet to all egress FDUs having at least one port associated with at least one receiver of the multicast packet; and

performing a lookup by each egress FDU in a synchronized local port state database to find a port for each receiver that is in an UP state.

12. The FDU of claim 11 wherein said forwarding the packet to all egress FDUs having at least one port associated with at least one receiver of the multicast packet further comprises:

determining if a receiver port is one of the group consisting of a stand alone port, an MLT group for a local FDU, and a MLT group for a remote FDU; and

forwarding a copy to each MLT member.

13. The FDU of claim 12 wherein when said receiver port is a stand alone port then determining whether said standalone port is in an UP state or a DOWN state, forwarding said packet out said port to a receiver when said port is in the UP state and dropping said packet when said port is in the DOWN state.

14. The FDU of claim 12 wherein when said receiver port is an MLT group for a local FDU then locating a local port member from the local port state table that is in an UP state.

15. The FDU of claim 14 further comprising forwarding said packet out said port that is in an UP state and dropping said packet by all remote FDUs.

16. The FDU of claim 14 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said local port state database.

17. The FDU of claim 12 wherein when said receiver port is an MLT group for a remote FDU then checking remote port tables to determine whether any MLT ports on originating network element are in the UP state.

18. The FDU of claim 17 further comprising when one MLT port on the originating network element are in the UP state then dropping said packet by said remote FDUs.

19. The FDU of claim 17 further comprising when all MLT ports on the originating node are down then selecting one remote port to transmit said packet and dropping said packet by all other remote ports.

20. The FDU of claim 17 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said remote port state database.

21. A computer readable storage medium having computer readable code thereon for providing a fast re-route of a multicast packet within a network element to an available port associated with a multi-link trunk, the medium including instructions in which a Forwarding Data Unit (FDU) performs operations comprising:

receiving a packet by said FDU in a data plane of a network element;

determining that the packet is a multicast packet;

forwarding the packet to all egress FDUs having at least one port associated with at least one receiver of the multicast packet, wherein said forwarding the packet to all egress FDUs having at least one port associated with at least one receiver of the multicast packet further comprises determining if a receiver port is one of the group consisting of a stand alone port, an MLT group for a local FDU, and a MLT group for a remote FDU;

wherein when said receiver port is a stand alone port then determining whether said standalone port is in an UP state or a DOWN state, and forwarding said packet out said port to a receiver when said port is in the UP state and dropping said packet when said port is in the DOWN state;

wherein when said receiver port is an MLT group for a local FDU then locating a local port member from the local port state table that is in an UP state, and forwarding said packet out said port to a receiver when said port is in the UP state and dropping said packet when a port in the UP state cannot be determined; and

wherein when said receiver port is an MLT group for a remote FDU then checking remote port tables to determine whether any MLT ports on originating network element are in the UP state; and

forwarding said packet out said port to a receiver when said port is in the UP state and dropping said packet when a port in the UP state cannot be determined.