AS path regular expressions extension to ripe 181

Marten Terpstra (marten at baynetworks.com) on June 13:
> 
> 
>  * The following three <extended routing policy expression> represent the same
>  * set of routes, however the last one can be translated into a finte state
>  * 
>  *                                      4
>  * 
>  * automota much more efficiently than the second one, and the second one can
>  * be translated much more efficiently than the first one:
>  * 
>  *   o <^AS1> OR < ^AS2> OR < ^AS3>
>  * 
>  *   o <^(AS1 | AS2 | AS3)>
>  * 
>  *   o <^[AS1 AS2 AS3]>
>  * 
>  * We recommend the use of the last form whenever possible.
> 
> Hmm, I would have picked another example here. On a specific peer, I
> cannot see how accepting routes with a path that starts with 3
> different ASes can be useful. The path will always start with the
> neighbor AS (unless you fiddle with the path of course). The example
> would have made more sense (to me at least) if you would have used
> 
> <AS1$> OR <AS2$> OR <AS3$> -> <(AS1 | AS2 | AS3)$> -> <[AS1 AS2 AS3]$>
> 
> -Marten

Good point. But I was actually thinking of as-out. That is you want to
announce all routes that you received from AS1, AS2 or AS3.

Actually your example is better and does not cause confusion. I will
change it.

Thanks.

Cengiz

-- 
Cengiz Alaettinoglu       Information Sciences Institute
(310) 822-1511            University of Southern California
http://www.isi.edu/div7/people/cengiz.home



-------- Logged at  Tue Jun 13 23:32:07 MET DST 1995  ---------