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.
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. 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.
but, as jared was talking about filtering of routes, forwarding path is quite irrelevant. randy
participants (2)
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Randy Bush
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Sean M. Doran