Hmm, this message bombed for some reason yesterday, and it looks like it didn't make it to anyone on the list. Since it sort of clarifies what I'm trying to say, I'm forwarding it on... Thanks, Milo ------- Forwarded Message Return-Path: postmaster@merit.edu Return-Path: <postmaster@merit.edu> Received: Thu, 1 Oct 92 12:26:04 PDT from kiddo.merit.edu by nsipo.arc.nasa.gov (4.1/1.5) Received: Mon, 31 Aug 92 05:38:55 -0400 from merit.edu by kiddo.merit.edu (AIX/1.6) Date: Mon, 31 Aug 92 05:38:55 -0400 From: Mail Delivery Subsystem <postmaster@merit.edu> Subject: Returned mail: unknown mailer error 2 Message-Id: <9210011927.AA16009@kiddo.merit.edu> To: <medin@nsipo.nasa.gov> ----- Transcript of session follows ----- ----- Unsent message follows ----- Received: Thu, 1 Oct 92 15:27:16 -0400 from merit.edu by kiddo.merit.edu (AIX/1.6) Return-Path: <medin@nsipo.nasa.gov> Received: from cincsac.arc.nasa.gov by merit.edu (5.65/1123-1.0) id AA18964; Thu, 1 Oct 92 15:22:55 -0400 Received: Thu, 1 Oct 92 12:22:53 PDT from localhost.arc.nasa.gov by cincsac.arc.nasa.gov (4.1/1.5T) Message-Id: <9210011922.AA25507@cincsac.arc.nasa.gov> To: skw@merit.edu Cc: mak@merit.edu, bjp@sura.net, regional-techs@merit.edu Subject: Re: ANS to CIX Interconnection In-Reply-To: Your message of "Thu, 01 Oct 92 04:47:26 EDT." <9210010847.AA08821@home.merit.edu> Date: Thu, 01 Oct 92 12:22:52 -0700 From: "Milo S. Medin" (NASA ARC NSI Office) <medin@nsipo.nasa.gov> Ok, I think I'm beginning to understand this better. So, the AS 1957 announcements will not be used as backup for CIX attached AS's to non CO+RE subscribers? It's only for use for the commercial types. One reason why I think some people are very interested in this issue of default routing to the NSF causing reachibility to CIX connected facilities is that as I understand it, there is a charge associated with the CO+RE service, which is supposed to go into some sort of pool to be distributed in various ways. Now, if a regional doesn't sign the CO+RE agreement, but because of default routing sends IP packets to CIX connected sites to their local ENSS, will they be charged for this in some manner? If not, then why should any regional be a CO+RE subscriber? Since they mostly point default at the ENSS already, and then they get connectivity without charge. You see, I think you guys have the greatest reason to not have AS 1957 routes installed in the routing tables of the various ENSS's whose members don't subscribe. Otherwise, those attached AS's could use the CO+RE service, and without an agreement, you could not be compensated for this. And I should point out that if you aren't compensated for this by the CIX folks (no settlements there) and by the regionals (because they just point default at you), then NSF would be placed in the position of supporting non-AUP traffic on resources it pays for. Now, you could legitimately point out that the since the CIX doesn't have a default pointing at the ENSS, that the packets from the non CO+RE subscribing regional would not get back that way, because you would not be sending those CO+RE nets to the CIX. However, I would venture a bet that most of the AS's which attach to the CIX have default pointing at some ENSS, or a router that has total routes from the ENSS. This means that the regional would route to the CIX net via the ANS-CIX interconnect, and then back from the CIX member via their "normal" internet path. So you still get connectivity, albeit with an asymmetric path. This is why some AS who doesn't want CIX connectivity established basically MUST not have a default pointing at an ENSS, but have to recieve total routes (- AS 1957) and run with no default. Because the reverse path will likely still work by following default back to the NSS system. This isn't a problem for us, but might be a problem for others. Now, there are other problems even if you go ahead and not flood AS 1957 routes into the ENSS's that non-CO+RE AS's attach to. For example, if one AS which peers with an ENSS goes the CO+RE route, then the ENSS would have the AS 1957 routes in it's routing table. But since it's the case at several sites that multiple AS's peer with the ENSS, a non CO+RE subscriber AS could point default at the ENSS and gain connectivity with CIX nets because the ENSS had those routes to support the CO+RE subscriber. Things get very complicated here. I presume there is no way you can send a bill to someone you don't have a contract with, so you really need some way of enforcing the charging scheme that's been developed, else you guys will have to result in filtering at the packet forwarding level to prevent that traffic from flowing. Do the NSS routers let you do that? Again, havi ------- End of Forwarded Message