Efficient multicasting in a distributed system architecture

A method of multicasting a packet comprising:

• receiving the packet at a line card of a plurality of line cards in a system;
• determining if the packet requires multicasting;
• sending, responsive to the packet requiring multicasting, the packet with a multicast header to a fabric switch of the system;
• replicating, by the fabric switch, the packet to obtain a replicated packet;
• sending, by the fabric switch, the replicated packet to one or more line cards of the plurality of line cards;
• determining, by a line card of the plurality of line cards, if any egress endpoints of a service associated with the packet are ineligible to receive a duplicate packet of the replicated packet;
• and
• providing the duplicate packet to each egress endpoint of the service except any such egress endpoint determined to be ineligible to receive the duplicate packet,
• wherein the packet is a Virtual Private Local Area Network (LAN) Service (VPLS) packet, the egress endpoints are VPLS egress endpoints, and the service is a VPLS service,
• wherein determining if any VPLS egress endpoints are ineligible to receive the duplicate packet comprises:
• determining, for each VPLS egress endpoint, if a destination endpoint identifier of the VPLS packet matches the VPLS egress endpoint;
• determining, responsive to a first VPLS egress endpoint matching the destination endpoint identifier, if the destination endpoint identifier matches a source endpoint identifier of the VPLS packet;
• and
• determining that the first VPLS egress endpoint is ineligible to receive the duplicate packet responsive to the destination endpoint identifier matching the source endpoint identifier.

A method of multicasting a packet comprising:

• receiving the packet at a line card of a plurality of line cards in a system;
• determining if the packet requires multicasting;
• sending, responsive to the packet requiring multicasting, the packet with a multicast header to a fabric switch of the system;
• replicating, by the fabric switch, the packet to obtain a replicated packet;
• sending, by the fabric switch, the replicated packet to one or more line cards of the plurality of line cards;
• determining, by a line card of the plurality of line cards, if any egress endpoints of a service associated with the packet are ineligible to receive a duplicate packet of the replicated packet;
• and
• providing the duplicate packet to each egress endpoint of the service except any such egress endpoint determined to be ineligible to receive the duplicate packet,
• wherein the packet is a Virtual Private Local Area Network (LAN) Service (VPLS) packet, the egress endpoints are VPLS egress endpoints, and the service is a VPLS service,
• wherein determining if any VPLS egress endpoints are ineligible to receive the duplicate packet comprises:
• determining, for each VPLS egress endpoint, if a destination endpoint identifier of the VPLS packet matches the VPLS egress endpoint;
• determining, responsive to a first VPLS egress endpoint matching the destination endpoint identifier, if the destination endpoint identifier and a source endpoint identifier of the VPLS packet belong to a same split horizon group;
• and
• determining that the first VPLS egress endpoint is ineligible to receive the duplicate packet responsive to the destination endpoint identifier and the source endpoint identifier belonging to the same split horizon group.

A method of multicasting a packet comprising:

• receiving the packet at a line card of a plurality of line cards in a system;
• determining if the packet requires multicasting;
• sending, responsive to the packet requiring multicasting, the packet with a multicast header to a fabric switch of the system;
• replicating, by the fabric switch, the packet to obtain a replicated packet;
• sending, by the fabric switch, the replicated packet to one or more line cards of the plurality of line cards;
• determining, by a line card of the plurality of line cards, if any egress endpoints of a service associated with the packet are ineligible to receive a duplicate packet of the replicated packet;
• and
• providing the duplicate packet to each egress endpoint of the service except any such egress endpoint determined to be ineligible to receive the duplicate packet, wherein the packet is a Virtual Private Local Area Network (LAN) Service (VPLS) packet, the egress endpoints are VPLS egress endpoints, and the service is a VPLS service,
• wherein determining if any VPLS egress endpoints of the VPLS service are ineligible to receive the duplicate packet comprises:
• determining that a first VPLS egress endpoint of the VPLS service matches a destination endpoint identifier of the VPLS packet and a source endpoint identifier of the VPLS packet, thereby making the first VPLS egress endpoint ineligible to receive the duplicate packet,
• wherein determining if any VPLS egress endpoints of the VPLS service are ineligible to receive the duplicate packet further comprises:
• determining that a second VPLS egress endpoint matches the destination endpoint identifier of the VPLS packet;
• and
• determining that the destination endpoint identifier and the source endpoint identifier are in a same split horizon group, thereby making the second VPLS egress endpoint ineligible to receive the duplicate packet.

An apparatus for multicasting a packet comprising:

• a first device operable to receive the packet;
• and
• a fabric switch coupled to the first device via a first fabric link, the fabric switch being operable to receive the packet from the first device and to replicate the packet to obtain a replicated packet,
• wherein the first device is further operable to:
• determine if the packet requires multicasting,
• send, responsive to the packet requiring multicasting, the packet with a multicast header to the fabric switch,
• receive the replicated packet from the fabric switch
• determine that an egress endpoint of a service associated with the packet and that corresponds to the first device is ineligible to receive a duplicate packet of the replicated packet, and
• provide the duplicate packet to egress endpoints of the service that correspond to the first device except such egress endpoints determined to be ineligible;
• and
• a second device coupled to the fabric switch via a second fabric link, the second device being operable to:
• receive the replicated packet from the fabric switch,
• determine an egress endpoint of a service associated with the packet and that corresponds to the second device is ineligible to receive the duplicate packet, and
• provide the duplicate packet to egress endpoints of the service that correspond to the second device except such egress endpoints determined to be ineligible.