Dave, I think this depends on what problem you're trying to solve. In the case of mobility and multihoming, you might want a stable identifier on a per-packet basis which is independent of the routing layer. This is the classic problem that mobile IP solves, and I believe is also the jist of what HIP was trying to address as well (or at least one of them). One might even be able to make a case that an IPsec SPI could serve the same purpose.
In all of these cases, a domain name per se would not work well since it's too big. As you point out, domain name as some form of session establishment seems plausible, but it is clearly not suited to the per-packet job which we have in various forms these days. Mike Dave Crocker writes: > Honest. I'm really sorry to have to send this query. > > In looking over various archives and documents, on the matter of separating > node address from node identifier, I have not been able to find or develop a > clear summary of the reasons the identifier cannot be a domain name. > > There are plenty of notes assuming that a new name space is needed. And there > are plenty of statements that say a new name space is needed because it will > make certain things better. > > But I have not seen a clear summary of what will be made better nor a clear > argument against using domain names, as the stable, public, > address-independent end-point identifier. > > I recall seeing a note from Christian Huitema that raised some interesting > concerns about using domain names, but I haven't been able to recover it. > > If the identifier is used only occasionally, such as at the start of an > association and during occasional state changes, then it is acceptable to have > the string be a bit long. If it must be in every packet, clearly it needs to > be short. If the identifier needs to be in every packet, then why? > > The string must be globally assigned only if it is needed for some sort of > rendezvous or third-party validation effort. Otherwise, the string can be > local to the association context, in the manner of purpose-built keys. > > So a new, global identifier space seems to be needed only if every packet is > subject to some sort of rendezvous or third-party validation. > > What am I missing? > > /d > -- > Dave Crocker <dcrocker-at-brandenburg-dot-com> > Brandenburg InternetWorking <www.brandenburg.com> > Sunnyvale, CA USA <tel:+1.408.246.8253> > > -------------------------------------------------------------------- > IETF IPng Working Group Mailing List > IPng Home Page: http://playground.sun.com/ipng > FTP archive: ftp://playground.sun.com/pub/ipng > Direct all administrative requests to [EMAIL PROTECTED] > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------