The AS I worked at back in the day did to a degree for willing parties. Mostly small ISPs who all knew each other. We had at the time 3 regional hub locations with interlinks, and peered settlement free with 2 - 3 ASs in 1 of the locations, and 1-2 ASs each in the other 2 locations, all of which could opt to allow their prefixes to be heard by the others via communities.
-Blake On Wed, Mar 5, 2014 at 3:48 PM, Siegel, David <david.sie...@level3.com>wrote: > I can't think of any circumstances where the business "B" would be content > transit traffic between A and C without some form of compensation. That > compensation may not involve payment for bits, however. In theory, the > compensation might be derived from something occurring at the application > layer, but even in those cases that business relationship is probably not > apparent from looking at prefix advertisements. Business B is probably > using b2b user agents, gre encap or some other method that makes both legs > look like independent IP flows to network A and B. > > Interesting question, though. > > > > Dave > > > -----Original Message----- > From: William Herrin [mailto:b...@herrin.us] > Sent: Wednesday, March 05, 2014 2:08 PM > To: Valdis Kletnieks > Cc: nanog@nanog.org > Subject: Re: valley free routing? > > On Wed, Mar 5, 2014 at 4:00 PM, <valdis.kletni...@vt.edu> wrote: > > On Wed, 05 Mar 2014 15:23:55 -0500, William Herrin said: > >> Can anyone tell me about a situation in which a route which was not > >> valley free was not a result of a misconfiguration or a bad actor? > >> For those who don't recall the terminology, a network path is valley > >> free if it crosses exactly zero or one free peering links when > >> traveling between the two endpoints. > > > > Assume 3 providers A B and C, where you have a single-homed customer > > on A and a single-homed customer on C, and A and C don't peer. > > Traffic may end up going thorugh an A-B peering and a B-C peering. And > > whether A-B and B-C are a free peering or a paid transit is a business > > deal, outside the scope of BGP, unless you want to abuse communities... > > > > Are A and/or C "bad actors" for not peering? Jury is still out on that > one. > > Hi Valdis, > > It's that business deal I want to hear about. When A-B and B-C are free > peering but the traffic goes A-B-C for some reason other than a > misconfiguration or deliberate abuse. On or off list, I'd like to know > about real-life use cases where folks do this on purpose. > > Regards, > Bill Herrin > > > -- > William D. Herrin ................ her...@dirtside.com b...@herrin.us > 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls > Church, VA 22042-3004 > > >
