Asymetrical Routing

Vadim Antonov avg at
Fri Aug 22 20:07:33 UTC 1997

Peter Kline wrote:
> but most of all:
> - possibly without justification, end users think that Symmetric Routing is
> the "right thing" to do, so therefore Asymmetric Routing is the "wrong
> thing" to do
This is way too soft-spoken.

Asymmetrical routing is a _necessary_ feature of modern
routing architectures.

It is _not_ possible to "decouple" interior routing between
backbones and preserve symmetricity of traffic flows.

(Note that things like injecting IGP metrics into MEDs do
not scale).

In other words, anyone who complains about asymmetricity of
backbone routing simply does not have a clue.


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