I have a /24 allocated to my by XO Communications in Phoenix, AZ (67.X.X.0/24). I am currently announcing it to Verio in Europe. A friend of mine that is an XO customer in Phoenix with BGP to XO can get to that address block within XO's network. But on the flip side. I also have a /22 from AT&T (12.X.X.0/22). When I announce that network block to Verio in Europe (and nowhere else), only certain places get to the Europe location. Networks that prefer AT&T go to AT&T's network and die since the route isn't there. I don't know if I am missing something but it think it may have to do with how the network's peering/filter schemes work. I may just be walking around the problem since I am a transit customer of Verio and they normally filter. -Andy --- Phil Rosenthal <pr@isprime.com> wrote:
On Oct 15, 2003, at 5:24 PM, H. Michael Smith, Jr. wrote:
What about the /24's that many ISPs (especially tier 2-3) are
assigning
to multi-homed customers? What about an IX or "critical infrastructure providers" that may be issued a /24 from ARIN (Policy 2001-3)?
As long as it's provider assigned, and your provider announces the supernet that the /24 is from, it will still work. If you announce PI space out of the old class A space in /24's, many networks wont be able to reach you.