[enum-wg] Follow up on Jim Reid's presentation - CRUE and relation to IETF work

On Apr 28, 2006, at 07:58, Michael Haberler wrote:

> I'm a bit puzzled though about your slides where you mention  
> "CRUE" (Carrier Registration in User ENUM) and its potential  
> international interoperability aspects.
>
> currently the IETF work on Infrastructure ENUM is progressing  
> nicely - I expect the long-run solution to be a separate apex (like  
> ie164.arpa for instance) and http://www.enum.at/ietf/draft-haberler- 
> carrier-enum-02.html will be the backwards-compatible interim  
> solution until ITU and friends have their act together. Looks like  
> all this is done this year. This will provide a easy manageable  
> home for carrier-related information.

Michael, CRUE has no bearing whatsoever on Infrastructure ENUM. This  
will be apparent when the CRUE document is published on the new UK  
ENUM web site. [I'll make an announcement about that when it goes on- 
line.] The object of CRUE is to get lots of meaningful data into the  
UK ENUM tree so that ENUM-aware applications can be encouraged  
because there's a better chance of getting a successful ENUM lookup.

The scheme is simple. Communications Service Providers register a  
block of numbers. This gets verified against the regulator's public  
database of block allocations to CSPs. The registry enters 2 NAPTRs  
for these numbers: a tel: URI and a sip: URI. The only "control" the  
CSP has here is the name of the SIP server: ie how non-PSTN calls can  
be terminated on their network. Now there's a lot of detail about  
ported numbers, allocation to end users and so forth. But that still  
doesn't make CRUE a replacement for "Infrastructure ENUM" whatever  
that happens to mean today.

BTW I don't share your optimism that standardisation of Carrier ENUM  
can be completed this year. But let's not jump down that rat-hole.

> I'm a bit concernced about diverging developments - maybe you can  
> enlighten us where you're heading and how this will interoperate   
> with the rest of us.

CRUE is not a "standard". Or a protocol. It's just a means to get  
lots of NAPTRs populating the 4.4.e164.arpa name space. So there are  
no interoperability issues.