Re: valley free routing?

[JÁKÓ András <jako.andras () eik bme hu>]

> 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.

As far as I understand some NRENs do that in Europe. Check out AS1853
and AS-ACONETTOVIX in the RIPE whois. "A" networks are the peers a VIX,
"B" is ACONET, "C" networks are CESNET, SANET, and PIONIER.

DTAG's looking glass shows this path to SANET:

sh ip bgp regexp _2607_
BGP table version is 0, local router ID is 217.239.38.165
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
                            r RIB-failure, S Stale, R Removed
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*>i147.175.0.0      194.25.5.150                  100      0 1853 2607 i
*>i147.213.0.0      194.25.5.150                  100      0 1853 2607 i
*>i147.232.0.0      194.25.5.150                  100      0 1853 2607 i
*>i158.193.0.0      194.25.5.150                  100      0 1853 2607 i
*>i158.195.0.0      194.25.5.150                  100      0 1853 2607 i
*>i158.197.0.0      194.25.5.150                  100      0 1853 2607 i
*>i192.108.130.0    194.25.5.150                  100      0 1853 2607 i
*>i192.108.131.0    194.25.5.150                  100      0 1853 2607 i
*>i192.108.132.0/23 194.25.5.150                  100      0 1853 2607 i
*>i192.108.138.0    194.25.5.150                  100      0 1853 2607 i
*>i192.108.149.0    194.25.5.150                  100      0 1853 2607 i
*>i193.87.0.0/16    194.25.5.150                  100      0 1853 2607 i
*>i194.1.0.0/17     194.25.5.150                  100      0 1853 2607 i
*>i194.160.0.0/16   194.25.5.150                  100      0 1853 2607 i
Total number of prefixes 14

Regards,
András