The Routing Over Large Clouds Mailing List Archive by date

[Telford001@aol.com]

> Minutes of the Routing Over Large Clouds Working Group (ROLC)


>Working Group Goals and Technical Problem Statement

>Analyze and propose enhancements to IP [and IPng] routing over large
>Analyze and propose enhancements to IP [and IPng] routing over large
>``shared media'' link layer (with respect to IP) networks (ATM, Frame
>``shared media'' link layer (with respect to IP) networks (ATM, Frame
>Relay, X.25, SMDS, etc.).

Wide-area links connected via wide-area MAC-bridges running a path
Wide-area links connected via wide-area MAC-bridges running a path
selection protocol like spanning tree or source routing can be used
to build the switching fabric of a "Large Cloud" and should be added
to the considerations of ROLC.

>Avoid ``extra hops'' when routing IP. Extra hops are defined as points
>Avoid ``extra hops'' when routing IP. Extra hops are defined as points
>where an IP datagram leaves and re-enters the same link-layer-cloud as a
>result of an IP routing decision, such as when routing between different
>IP subnets overlaid on the same cloud.

Such a rule or recommendation is inappropriate.  This issue is a question
of  internet design and not a question of protocol standardization.

It might make perfect sense to leave and reenter the "cloud" if selecting
a path which remains within the cloud necessitates transversal of a link
which has extremely low data rate or some other negative characteristic
whereas the path which requires the external hop uses links of appropriate
characterists.

Joachim Carlo Santos Martillo Ajami
Joachim Carlo Santos Martillo Ajami