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Flexible Multilevel TRILL (Transparent Interconnection of Lots of Links)
draft-perlman-trill-rbridge-multilevel-08

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
Expired & archived
Authors Radia Perlman , Donald E. Eastlake 3rd , Anoop Ghanwani , Hongjun Zhai
Last updated 2015-01-01 (Latest revision 2014-06-30)
Replaced by draft-ietf-trill-rbridge-multilevel, RFC 8243
RFC stream (None)
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Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
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Responsible AD (None)
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:

Abstract

Extending TRILL to multiple levels has one challenge that is not addressed by the already-existing capability of IS-IS to have multiple levels. The issue is with TRILL switch nicknames. There have been two proposed approaches. One approach, which we refer to as the "unique nickname" approach, gives unique nicknames to all the TRILL switches in the multilevel campus, either by having the level-1/level-2 border TRILL switches advertise which nicknames are not available for assignment in the area, or by partitioning the 16-bit nickname into an "area" field and a "nickname inside the area" field. The other approach, which we refer to as the "aggregated nickname" approach, involves assigning nicknames to the areas, and allowing nicknames to be reused in different areas, by having the border TRILL switches rewrite the nickname fields when entering or leaving an area. Each of those approaches has advantages and disadvantages. The design in this document allows a choice of approach in each area, allowing the simplicity of the unique nickname approach in installations in which there is no danger of running out of nicknames, and allowing nickname rewriting to be phased into larger installations on a per-area basis.

Authors

Radia Perlman
Donald E. Eastlake 3rd
Anoop Ghanwani
Hongjun Zhai

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