Mike, Generally a netblock is homed somewhere if it doesn't have an association with an ASN. These will often be listed as "non-portable", and then each ISP would have to choose to allow you to use that netblock on its network or not. Based on your company name and domain I assume your netblock is 192.67.91.0/24, which shows as a Direct Assignment, so you should have the right to move it. I think what you are asking is unusual because you have address space you are trying to move, but no ASN for the carrier to advertise the route to. In terms of terminology I think "advertise our netblock in your AS" is about as close as you can get, and you are at ATT's mercy because they have the right to create their own policies about advertising client's netblocks as part of their AS. I would say they would most likely want to handle this by assigning you an iBGP ASN so you can advertise that block to them privately, and then they would aggregate that advertisement into their eBGP advertisements for their AS. There should be no reason to require 2 distinct routers just to use BGP. Your other option is to get a cheap link from another provider that does not include any usage, and use that as the second (backup) link. At that point you could get an ASN assigned by ARIN. -Scott -----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Mike Donahue Sent: Wednesday, January 16, 2008 4:37 PM To: nanog@merit.edu Subject: request for help w/ ATT and terminology Hi. I'm by no means an ip/networking expert, and we're having some difficulty communicating with the boffins at AT&T. Any input/advice/translation would be appreciated. We own our own class C netblock. Our previous provider, Sprint, had no problem "adding" it to their network/advertising it (that circuit is now disconnected). We've started using an AT&T colo facility, and we're having a lot of trouble trying to get AT&T to do the same thing there that Sprint was able to do for us. AT&T is refusing to advertise our netblock/path it to our cabinet unless we have an AS number. ARIN has refused to give us one on the grounds (rightly so) that we're not multi-homed. AT&T says they'll give us a temporary ASN, and want us to do eBGP for our netblock. They sent the technical information over today, and they want two distinct routers to act as the bgp peers... Anyway, it's all getting (for us) pretty complicated. We're a fairly small firm and just want an Ethernet handoff with our IP block on it. Sprint didn't blink at the request, but AT&T... We're getting a good rate from AT&T for the IP services because it's at their colo. Switching back to Sprint would definitely be more costly. Questions: 1. Is what we're asking for unusual/uncalled for? 2. What's the technical terminology for the request for AT&T to simply start advertising our netblock called? I'm wondering if they're not understanding our request. Any other comments/input/suggestions welcomed. Thanks in advance, Mike Donahue WATG