Anyone notice strange announcements for

David Barak thegameiam at
Tue Jan 13 16:53:42 UTC 2009

--- On Tue, 1/13/09, Jared Mauch <jared at> wrote:
> 	No, they are both victims.  If I inject a path that
> purports
> there is an edge between two networks which are engaged in
> a bitter
> dispute, (i'll use cogent & sprint as an example) -
> _1239_174_ that may
> create a situation where someone asserts that their routes
> are
> being filtered when infact no connectivity exists.

That's a theoretical possibility, but who would be the one doing the asserting?  I would argue that it would either be the owner of the announced space or someone trying to reach it.  In this case, nobody was trying to reach the /24 in question, and the owner was the one doing the experiment.  Victimless crime, at most.

> 	Does that mean that I hijacked their identiy and forged
> it?  What level of trust do you place in the AS_PATH for your
> routing, debugging and
> decision making process?

AS_PATH != identity, and I would not recommend loading the latter onto the former.

> 	Personally, I would be upset if someone injected a route
> with my ASN in the AS_PATH without my permission.

Why?  Is this a theoretical "because it's ugly" complaint, or is there a reason why manipulating this particular BGP attribute in this particular way is so bad?  Organizations do filtering and routing manipulation all over the place.  Is there something worse about doing it this way than others?

David Barak
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