On Wed, Jan 15, 2014 at 1:26 PM, William Herrin <b...@herrin.us> wrote: > On Wed, Jan 15, 2014 at 12:54 PM, Niels Bakker <niels=na...@bakker.net> wrote: >> * na...@shankland.org (Jim Shankland) [Wed 15 Jan 2014, 18:04 CET]: >> >>> So ... RFC1918 addresses for the IXP fabric, then? >>> >>> (Half kidding, but still ....) >> >> They need to be globally unique. > > Hi Niels, > > Actually, they don't. To meet the basic definition of working, they > just have to be able to originate ICMP destination unreachable packets > with a reasonable expectation that the recipient will receive those > packets. Global uniqueness is not required for that. However, RFC1918 > addresses don't meet the requirement for a different reason: they're > routinely dropped at AS borders, thus don't have an expectation of > reaching the external destination. > > Of course working, monitorable and testable are three different > things. If my NMS can't reach the IXP's addresses, my view of the IXP > is impaired. And "the Internet is broken" is not a trouble report that > leads to a successful outcome with customer support... it helps to be > able to pin things down with some specificity. > > Regards, > Bill Herrin
Using RFC1918 would incur the assumption that one will need to use a unique router or routing instance for every exchange connected to since exchanges are likely to have overlapping space at that point (RFC1918 IXP registry anyone?). I don't think it'd be a good idea to go down that path.. Also mentioned in a past nanog was the idea of potentially getting someone like team cymru to setup all exchange prefixes in a special bogon list and you could null route on your edge all those prefixes.. I inquired to team cymru about this back when originally discussed but never got anywhere with them. > > > -- > William D. Herrin ................ her...@dirtside.com b...@herrin.us > 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> > Falls Church, VA 22042-3004 > -- [stillwa...@gmail.com ~]$ cat .signature cat: .signature: No such file or directory [stillwa...@gmail.com ~]$
