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Multicast using Bit Index Explicit Replication

Document Type Replaced Internet-Draft (bier WG)
Expired & archived
Authors IJsbrand Wijnands , Eric C. Rosen , Andrew Dolganow , Tony Przygienda , Sam Aldrin
Last updated 2015-10-14 (Latest revision 2015-03-06)
Replaced by draft-ietf-bier-architecture
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Additional resources Mailing list discussion
Stream WG state Adopted by a WG
Document shepherd (None)
IESG IESG state Replaced by draft-ietf-bier-architecture
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


This document specifies a new architecture for the forwarding of multicast data packets. It provides optimal forwarding of multicast packets through a "multicast domain". However, it does not require any explicit tree-building protocol, nor does it require intermediate nodes to maintain any per-flow state. This architecture is known as "Bit Index Explicit Replication" (BIER). When a multicast data packet enters the domain, the ingress router determines the set of egress routers to which the packet needs to be sent. The ingress router then encapsulates the packet in a BIER header. The BIER header contains a bitstring in which each bit represents exactly one egress router in the domain; to forward the packet to a given set of egress routers, the bits corresponding to those routers are set in the BIER header. Elimination of the per-flow state and the explicit tree-building protocols results in a considerable simplification.


IJsbrand Wijnands
Eric C. Rosen
Andrew Dolganow
Tony Przygienda
Sam Aldrin

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)