[Asterisk-Users] No Caller Name sent from Asterisk over Nationalor DMS100 PRI to a Norstar MICS?

David Troy dave at popvox.com
Thu Sep 16 05:52:57 MST 2004


> The owner of the connection to the PSTN (Telco) must insert the NAME
> portion for Call Display. There is no way around that since its their
> database
> the NAME is located in. Someone correct me if I am wrong .

Yes, I think it's fair to say that the ILEC/CLEC to whom the phone number 
is routed is responsible for publishing reverse name lookup for that 
number.

This is somewhat analogous to in.addr.arpa reverse lookup for DNS.

It should be noted that, with LNP, any single phone number can be bound to 
any carrier, so there is not necessarily any notion of "native numbers" 
for a given carrier, etc.

That all being said, does anyone have any experience with what 
databases/mechanisms CLEC's might use to maintain and disseminate these 
reverse lookups?

I can think of some weird scenarios:

  A) 443-555-1212 is a published number for "Consolidated Cheese Corp" and 
is initially serviced by Verizon.
  B) "Consolidated Cheese" later ports 410-555-1212 to a facilities-based 
CLEC-provided PRI
  C) "Consolidated Cheese" signs up for a VoIP termination service and 
wants to set caller ID to 410-555-1212 for its PSTN-bound calls.  The VoIP 
termination service is provided by a different CLEC from (B), possibly in 
a different geography.

So, assuming CLEC in (B) has done its job and published some sort of 
reverse lookup for 410-555-1212, calls made via (C) should, in theory, 
correctly display Caller ID Name for the callee's.  But how?

The only way I can think of for this to work is for a dip to be made for 
the reverse lookup, presumably via a SS7 request, to the (B) CLEC, even 
though the call may not originate with, terminate on, or otherwise pass 
through (B)'s switch network.  (B) would only be touched for the reverse 
name lookup.

If this outline is close to reality, is there any notion of distributing 
these name lookups, a la DNS?  What about caching/TTL?  Where is this 
stuff written down?

Comments?

Dave



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