nanog mailing list archives
Re: Is the export policy selective under valley-free?
From: Valdis.Kletnieks () vt edu
Date: Wed, 03 Sep 2008 13:26:54 -0400
On Wed, 03 Sep 2008 10:36:52 +0200, William Waites said:
Valley-free is a property of AS mesh models that says that, where edges are classified as peering (p2p) or transit (c2p) that a valid path contains zero or one peering link and that the peering link occurs adjacent to the top of the path. That is that valid paths look like, [c2p c2p ... c2p p2p p2c ... p2c p2c]
OK, I'm looking at this, and having a *little* trouble buying that there's exactly zero or one p2p links - consider the case where the last 'c2p' link is to provider A, who peers with B but not C, and B peers with both A and C, and the first p2c link lands at C. Don't you end up with "cp2 p2p p2p p2c" in that case? Or is there a convention saying we compress the A-B and B-C links into a notational A-C link? Or are we defining A-B or B-C links as being a c2p type instead, even though they're peering and not transit?
Attachment:
_bin
Description:
Current thread:
- Is the export policy selective under valley-free? Kai Chen (Sep 02)
- Re: Is the export policy selective under valley-free? Paul Wall (Sep 02)
- Re: Is the export policy selective under valley-free? William Waites (Sep 03)
- Re: Is the export policy selective under valley-free? Valdis . Kletnieks (Sep 03)
- Re: Is the export policy selective under valley-free? William Waites (Sep 03)
- Re: Is the export policy selective under valley-free? Valdis . Kletnieks (Sep 03)
- Re: Is the export policy selective under valley-free? Iljitsch van Beijnum (Sep 03)
- Re: Is the export policy selective under valley-free? William Waites (Sep 03)
- Re: Is the export policy selective under valley-free? Paul Wall (Sep 02)
- Re: Is the export policy selective under valley-free? William Waites (Sep 03)
- Re: Is the export policy selective under valley-free? Randy Bush (Sep 03)
- Re: Is the export policy selective under valley-free? William Waites (Sep 03)
- Re: Is the export policy selective under valley-free? Randy Bush (Sep 03)
- Re: Is the export policy selective under valley-free? Iljitsch van Beijnum (Sep 03)