[20220] in North American Network Operators' Group

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Re: [YA] Fwd: Class B Purchase

daemon@ATHENA.MIT.EDU (Sean M. Doran)
Wed Oct 7 11:38:18 1998

From: "Sean M. Doran" <smd@clock.org>
To: jared@puck.nether.net
Cc: nanog@merit.edu
Date: 	Wed, 7 Oct 1998 08:21:10 -0700


Uhm but an AS-path is a trail of bread-crumbs to prevent an announcement
loop, not a proper predictor of the forwarding-path towards the origin.

Indeed, because of hop-by-hop routing, the ultimate destination may
have nothing to do with the originating AS.  Fun fun fun!

Consider what happens when, at an IX, one of the ASes in an AS path
gives you someone else's router address as a next-hop...

	Sean.
- --
Jared Mauch wrote:

| second, if they (AS5662) were connected to MCI/CW rather than
| Sprint, they would be unreachable with this announcement, other
| than the fact that ANS would be announcing the aggregate, and following
| that path, rather than having the actual as-path be traversed.

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