[Ietf-not43] extensibility

[Michael.Dillon at radianz.com]

>I also should point out that I'm far from having a real, precise 
>reason to disagree, I'm asking in a discovery mode.  I have yet to be 
>convinced that DNS is the end-all for the purpose here (thinking of 
>the domainComponents). 

I agree that other mechanisms are possible, not just DNS. I think that
the characteristics of DNS that lead one to think of it first are its
scalability, notably the ability for caching servers to act as 
intermediaries
and cache replies, and also its referral capability.

Now, both of these things could technically be done with LDAP instead of
DNS. In other words, to find the FIRS server with information for a given
IP address such as 192.0.0.7 you would:

1. Query your local FIRS server. If it didn't have the answer it would

2. Query the IANA FIRS server on your behalf. This server would return
   a referral to one of the RIR servers such as ARIN

3. Your FIRS server would then query the ARIN server. ARIN's server would
   return a referral to an ISP's FIRS server

4. Your FIRS server would then query the ISP's server and receive an
   authoritative reply.

5. All of this information would be cached by your FIRS server and the
   authoritative reply would be passed on to you.

A short time later, another user who shares the same local FIRS server
would do a query on 192.0.0.8 and your local FIRS server would go directly
to the correct ISP's FIRS server because it has cached the IANA and RIR
lookup info.

In this context, there is no such thing as a reverse map, just an 
allocation
hierarchy that you can walk and cache. The major difference is that this 
scenario
assumes that FIRS clients prefer to talk to a local FIRS resolver rather 
than
walk the hierarchy themselves.

--Michael Dillon