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
View Patent ↗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.
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, said forwarding including determining if a receiver port is one of the group consisting of a stand alone port, a Multi Link trunk (MLT) group for a local FDU, and a MLT group for a remote FDU and forwarding a copy to each MLT member; 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 when said receiver port is a standalone 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.
3. The method of claim 1 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.
4. The method of claim 3 further comprising forwarding said packet out said port that is in an UP state and dropping said packet by all remote FDUs.
5. The method of claim 3 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said local port state database.
6. The method of claim 1 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.
7. The method of claim 6 further comprising when one MLT port on the originating network element are in the UP state then dropping said packet by said remote FDUs.
8. The method of claim 6 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.
9. The method of claim 6 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said remote port state database.
10. 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, wherein said forwarding including determining if a receiver port is one of the group consisting of a stand alone port, a Multi Link trunk (MLT) group for a local FDU, and a MLT group for a remote FDU and forwarding a copy to each MLT member; 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.
11. The FDU of claim 10 wherein when said receiver port is a standalone 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.
12. The FDU of claim 10 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.
13. The FDU of claim 12 further comprising forwarding said packet out said port that is in an UP state and dropping said packet by all remote FDUs.
14. The FDU of claim 12 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said local port state database.
15. The FDU of claim 10 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.
16. The FDU of claim 15 further comprising when one MLT port on the originating network element are in the UP state then dropping said packet by said remote FDUs.
17. The FDU of claim 15 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.
18. The FDU of claim 15 wherein a MLT Identifier (ID) and hash value are used to perform said lookup in said remote port state database.
19. A non-transitory 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, a Multi Link Trunk (MLT) group for a local FDU, and a MLT group for a remote FDU;
wherein when said receiver port is a standalone 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.