Good question, Erik. To the best of my knowledge such an RFC does not exist - at least describing total details of an aggregation router - like unicast, mcast, and anycast data forwarding rules etc. The closest I have found in IETF is what IETF calls as multi-link router.
A cable aggregation router is described in a cable docsis standard. Look at the last standard by searching for this file. CM-SP-SECv3.0-I05-070803.pdf. It will take a person new to cable a long time to understand such a router behavior. I was here to explain that behavior in the slides. Anyhow, it's not rocket science to figure out basic behavior of a aggregation router. I presented my slides that said an aggregation router has subscriber hosts as always off-link to each other due to physical connectivity of deployment. Well, if hosts are always off-link, then the aggregation router is lying if the router sends any Redirects to signal any prefix as on-link to a host. That is why such a deployment for both IPv4 or IPv6 does not send Redirect. Now the question I asked in my presentation. I have to configure this aggregation router to signal off-link. How do I do that? Thanks. Hemant -----Original Message----- From: Erik Nordmark [mailto:[EMAIL PROTECTED] Sent: Wednesday, December 05, 2007 12:29 PM To: Hemant Singh (shemant) Cc: Suresh Krishnan; ipv6@ietf.org Subject: Re: Off-link and on-link Hemant Singh (shemant) wrote: > Suresh, > > At least our drafts do not ask for a new off-link flag. Without a new > off-link flag your scenario will have to go with (a). But do note, > aggregation routers do not send Redirects. So the scenario below > cannot be even supported on aggregation routers. Which RFC defines an "aggregation router"? Erik > > Hemant > > -----Original Message----- > From: Suresh Krishnan [mailto:[EMAIL PROTECTED] > Sent: Wednesday, December 05, 2007 11:01 AM > To: ipv6@ietf.org > Subject: Off-link and on-link > > Hi Hesham/Dave/Erik, > I am not taking a stand on whether an explicit off-link flag is > necessary/useful or not, but I have encountered a scenario where the > existing algorithm specified in RFC4861 does not work very well. Let's > say a router wants to signal to the clients that 2001:dead:beef::/48 > is on-link except for 2001:dead:beef:abcd::/64 that is off-link. How > would it go about describing this? I see two ways > > a) Advertise the /48 with L=0 and send redirects for all addresses not > on the /64 > b) Advertise the /48 with L=1 and the /64 with Q(the new off-link > flag)=0 > > I see b) as being more efficient than a) > > P.S: I do not think that this scenario is very likely, just possible. > > Cheers > Suresh > > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > ipv6@ietf.org > Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- > > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > ipv6@ietf.org > Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
