[6045] in North American Network Operators' Group

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Re: Why doesn't BGP...

daemon@ATHENA.MIT.EDU (Todd Graham Lewis)
Fri Nov 8 23:10:37 1996

Date: Fri, 8 Nov 1996 23:06:06 -0500 (EST)
From: Todd Graham Lewis <lists@reflections.mindspring.com>
To: Ed Morin <edm@halcyon.com>
cc: Marten Terpstra <marten@baynetworks.com>, nanog@merit.edu
In-Reply-To: <Pine.ULT.3.95.961108192749.19748C-100000@halcyon.halcyon.com>

On Fri, 8 Nov 1996, Ed Morin wrote:

> Is this really true?  All I'm asking for is that the route a router
> considers to be "best" be picked by something a little more rational
> than the ordinate order of its IP address relative to another link.
> I don't see a flap situation at all here -- only that a decision to
> route a packet may change more frequently based on load.

A decision to route a packet may change more frequently based on load.
And those decisions are propogated and acted upon by other routers.  And
they send traffic down those links.  And the load on those links changes.
And you make a new decision to route a packet based on the new load.


|                                      _
|                                      /|
|              /\                    /
|            /    \                /
| -^\/\    /        \            /
|       \/            \        /
|                       \    /
|                         \/
|
|
+----------------------------------------------

Unless you have a model which is provably resilient to these sorts of
feedback loops (which, to my understanding, BGP is not), then playing
these sort of tricks is a young man's game, and one guaranteed not to
leave him young (or employed) for long.

Statically adjust the preference on your links and count yourself lucky.
8^)

__
Todd Graham Lewis             Linux!                 Core Engineering
Mindspring Enterprises  tlewis@mindspring.com   (800) 719 4664, x2804


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