Method and apparatus for providing resiliency in multicast networks

A multicast edge network element to guarantee resilient multicast traffic stream processing of only a last hop of a multicast traffic stream towards a multicast receiver, comprising:

• an interface manager module to automatically configure a first interface on a first line card with a best route towards a source of the multicast traffic stream as determined by a unicast routing protocol module, to configure a second interface on a second line card as a backup interface, and to automatically configure a third interface with a best route towards the multicast source as determined by the unicast routing protocol module when packets of the multicast traffic stream received on the second interface are transitioned to being processed;
• a protocol independent multicast (PIM) module coupled with the first and second line cards, the PIM module to cause the multicast edge network element to join the multicast traffic stream through the first interface and to separately join an equivalent multicast traffic stream having a same multicast source and multicast group through the second interface to enable the first and second line cards to receive packets of the multicast traffic streams respectively, and further to cause the multicast edge network element to join the multicast traffic stream through the third interface when packets of the multicast traffic stream received on the second interface are transitioned to being processed;
• a multicast traffic stream failure detection module coupled with the first and second line cards, the multicast traffic stream failure detection module to detect one or more interruptions of the multicast traffic streams;
• and
• a line card manager coupled with the multicast traffic stream failure detection module and the first and second line cards, the line card manager to,
• cause packets of the multicast traffic stream that are to be received at the first line card to be processed and the packets of the equivalent multicast traffic stream that are to be received at the second line card to be dropped while the first line card receives those packets uninterrupted,
• cause a transition to process the packets of the equivalent multicast traffic stream that are to be received at the second line card if the multicast traffic stream failure detection module detects an interruption at the first line card of the receipt of the packets of the multicast traffic stream, and
• cause, upon the transition to process the packets of the equivalent multicast traffic stream that are to be received at the second line card, packets of the equivalent multicast traffic stream that are to be received at the third interface to be processed and to cause the packets of the equivalent multicast traffic stream that are to be received at the second line card to be dropped.

A non-transitory machine-readable storage medium that provides instructions that, if executed by a processor, will cause said processor to perform operations for a multicast edge network element guaranteeing resilient multicast traffic stream processing of only a last hop of the multicast traffic stream towards a multicast receiver, wherein the multicast edge network element is coupled with a first and second multicast core network element each capable of forwarding packets of an equivalent multicast traffic stream to the multicast edge network element and each is situated between a source of the multicast traffic stream and the multicast edge network element, comprising:

• separately joining through a first and second interface of the multicast edge network element the equivalent multicast traffic streams from the first and second multicast core network element respectively, wherein the equivalent multicast traffic streams have a same multicast source and multicast group;
• processing packets of the multicast traffic stream received at the first interface from the first multicast core network element, and while the first interface is receiving those packets uninterrupted, dropping packets of the equivalent multicast traffic stream received at the second interface from the second multicast core network element;
• and
• upon interruption of receipt of the packets of the multicast traffic stream at the first interface, transitioning to processing the packets of the equivalent multicast traffic stream subsequently being received at the second interface from the second multicast core network element;
• and
• after transitioning to processing the packets of the equivalent multicast traffic stream being received at the second interface from the second multicast core network element, performing the following,
• determining that a best route towards the source of the multicast traffic stream, according to a unicast routing protocol, is through a third multicast core network element, wherein the third multicast core network element is able to forward equivalent packets of the multicast traffic stream to the multicast edge network element and is situated between the source of the multicast traffic stream and the multicast edge network element,
• joining through a third interface of the multicast edge network element the equivalent multicast traffic stream from the third multicast core network element, and
• upon receiving packets of the multicast traffic stream on the third interface from the third multicast core network element, transitioning to performing the following,
• processing the packets of the multicast traffic stream received on the third interface from the third multicast core network element, and
• dropping the packets of the multicast traffic stream being received at the second interface from the second multicast core network element.