BIT INDEX EXPLICIT REPLICATION (BIER)FORWARDING FOR NETWORK DEVICE COMPONENTS

• US 20160191372A1
• Filed: 06/29/2015
• Published: 06/30/2016
• Est. Priority Date: 12/31/2014
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: ZHANG, Zhaohui, BABAN, Alex
• Granted Patent: US 9,705,784 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/30 Peripheral units, e.g. input or output ports
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags

Abstract

A network device receives multicast packets that include information identifying destinations in the network, identifies next hops associated with the destinations, and populates a cache with the destinations and addresses of the identified next hops. The network device receives a particular multicast packet that includes information identifying particular destinations included in the cache, identifies one or more next hops for the particular destinations from the cache, and forwards the particular multicast packet to the identified one or more next hops to permit the identified one or more next hops to forward the multicast packet toward the particular destinations.

Claims

1. A network device, comprising:

an ingress line card;

one or more egress line cards; and

one or more processors to;

modify a forwarding table to include information associated with the one or more egress line cards and information associated with masks for the one or more egress line cards,

the forwarding table including information associated with destinations and information associated with next hops for the destinations, and

the masks indicating destinations reachable via corresponding next hops;

receive, via the ingress line card, a multicast packet that includes information identifying destinations for the multicast packet;

identify an egress line card, of the one or more egress line cards, for receiving the multicast packet based on the information identifying the destinations and based on the modified forwarding table;

cause the ingress line card to provide the multicast packet to the identified egress line card;

create, via the identified egress line card, copies of the multicast packet; and

forward, via the identified egress line card, the copies of the multicast packet toward some of the destinations.

2. The network device of claim 1, where the one or more processors are further to:

store the modified forwarding table; and

program the modified forwarding into a data plane used to forward multicast packets.

3. The network device of claim 1, where the forwarding table further includes information associated with a plurality of destinations in a network and information associated with next hops for the plurality of destinations,

the plurality of destinations including the destinations.

4. The network device of claim 1, where the network device is associated with a bit index explicit replication (BIER) forwarding method.

5. The network device of claim 1, where, when forwarding the copies of the multicast packet, the one or more processors are further to:

identify particular next hops associated with the modified forwarding table and associated with some of the destinations; and

forward the copies of the multicast packet to the particular next hops to permit the particular next hops to forward the multicast packet toward some of the destinations.

6. The network device of claim 5, where,

when creating the copies of the multicast packet, the one or more processors are further to:

create a copy of the multicast packet for each of the particular next hops; and

when forwarding the copies of the multicast packet to the particular next hops, the one or more processors are further to;

forward a corresponding copy of the multicast packet to a corresponding one of the particular next hops.

7. A method, comprising:

modifying, by a network device provided in a network, a forwarding table to include information associated with one or more egress line cards of the network device and information associated with masks for the one or more egress line cards;

receiving, by an ingress line card of the network device, a multicast packet that includes information identifying destinations for the multicast packet;

identifying, by the network device, an egress line card, of the one or more egress line cards, for receiving the multicast packet based on the information identifying the destinations and based on the modified forwarding table;

causing, by the network device, the ingress line card to provide a single copy of the multicast packet to the identified egress line card;

creating, by the identified egress line card, copies of the multicast packet; and

forwarding, by the identified egress line card, the copies of the multicast packet toward some of the destinations.

8. The method of claim 7, further comprising:

programming the modified forwarding table into a data plane associated with the network device and used to forward multicast packets.

9. The method of claim 7, where the network device is associated with a bit index explicit replication (BIER) forwarding method.

10. The method of claim 7, where forwarding the copies of the multicast packet further includes:

identifying particular next hops associated with the modified forwarding table and associated with some of the destinations; and

forwarding the copies of the multicast packet to the particular next hops to permit the particular next hops to forward the multicast packet toward some of the destinations.

11. The method of claim 7, where the network device includes a bit forwarding device and the modified forwarding table includes a modified bit index forwarding table (BIFT).

12. The method of claim 7, where the forwarding table further includes information associated with a plurality of destinations in the network and information associated with next hops for the plurality of destinations,

the plurality of destinations including the destinations.

13. A network device associated with a bit index explicit replication (BIER) forwarding method, the network device comprising:

one or more processors to;

receive multicast packets that include information identifying destinations;

identify next hops associated with the destinations;

populate a cache with the destinations and addresses of the identified next hops;

receive a particular multicast packet that includes information identifying particular destinations;

determine whether the particular destinations are included in the cache; and

when the particular destinations are included in the cache;

identify one or more next hops for the particular destinations from the cache, and

forward the particular multicast packet to the identified one or more next hops to permit the identified one or more next hops to forward the multicast packet toward the particular destinations.

14. The network device of claim 13, where, when the particular destinations are not included in the cache, the one or more processors are further to:

identify particular next hops associated with the particular destinations; and

populate the cache with the particular destinations and addresses of the identified particular next hops.

15. The network device of claim 13, where, when forwarding the particular multicast packet to the identified one or more next hops, the one or more processors are further to:

create a copy of the multicast packet for each of the identified one or more next hops; and

forward the copy of the multicast packet to each of the identified one or more next hops.

16. The network device of claim 13, where the one or more processors are further to:

store the cache; and

program the cache into a data plane used to forward multicast packets.

17. The network device of claim 13, where, when the particular destinations are not included in the cache, the one or more processors are further to:

utilize a bit index forwarding table (BIFT) stored in the network device to identify particular next hops associated with the particular destinations.

18. A method, comprising:

receiving, by a network device in a network, multicast packets that include information identifying destinations in the network;

identifying, by the network device, next hops associated with the destinations;

populating, by the network device, a cache with the destinations and addresses of the identified next hops;

receiving, by the network device, a particular multicast packet that includes information identifying particular destinations,

the particular destinations being included in the cache;

identifying, by the network device, one or more next hops for the particular destinations from the cache; and

forwarding, by the network device, the particular multicast packet to the identified one or more next hops to permit the identified one or more next hops to forward the multicast packet toward the particular destinations.

19. The method of claim 18, where forwarding the particular multicast packet to the identified one or more next hops further includes:

creating a copy of the multicast packet for each of the identified one or more next hops; and

forwarding the copy of the multicast packet to each of the identified one or more next hops.

20. The method of claim 18, where identifying next hops associated with the destinations further includes:

utilizing a bit index forwarding table (BIFT) stored in the network device to identify the next hops associated with the destinations.