Ran Atkinson writes: | The semantics of an FQDN is not crisp and clear | these days as is once was. Wow, your memory must be better than mine if you remember crispness & clarity. :-) | For example, www.cnn.com names a set of content | rather than naming a single given host. | | Unicast ESP/AH SAs have to be between pairs of hosts. It's down to what kind of "who" you want to represent; I think it is reasonable to have more than one "who" namespace, allowing one to find a particular application (the web server that will cough up CNN's news, or the mail server that will receive mail for Ran Atkinson) as well as a particular host. This, moreover, makes application migration easier to deal with. Again, the trick is to be able to do a symmetrical mapping between "who-application" and "who-host". Here's a question for you: given these two namespaces (one being hypothetical), which one will find more common use by _you_? | So FQDNs can't quite do the trick, even with DNSSEC I think the argument goes that a DNS-like distributed database is a good idea, and that the DNS can be munged into doing the work initially without enormous effort. Yes, this means a different namespace or two beyond the "IN" one, but is that a big deal? | (NB: my analysis above assumes that DNSSEC is widely deployed | and ubiquitously available; in the current reality of very limited | DNSSEC deployment, things aren't quite as nice as what | I outline above). Well, so who wants to write a resolver that makes use of Jon Crowcroft's idea on replacing the existing DNS lookup mechanism? Sean.