The way carriers derive this information is from CIC codes (Carrier Identification Codes) embedded in the SS7 overhead. This is used for intercarrier compensation; which is the typical reason you'd care what carrier originated the call. For more info on CICs:
http://www.nanpa.com/number_resource_info/carrier_id_codes.html
It's a tricky problem to solve really in today new fangled telephony. What do you call the "originating carrier" The local provider? The end user? The wholesaler? The IXC? A call that hits you could have traversed a dozen networks and the originating network could have been a system as simple (or complex) as an asterisk box with one analog interface and no SS7 capabilities. Therefore unable to populate a CIC code. Therefore their upstream provider may populate that field.
Now, going by strict guidelines CallerID information (including callerid number) has NEVER been and should NEVER be used for routing of calls or rating of calls as this information is *very* easily changed. Billing should be based on BTN and routing should be based on ANI, originating trunk group or other trunk specific information (ie: for proper routing of 911 calls).
By the way, if anyone out there would like to comment on that premise, I'd love to hear what some of you think regarding routing/rating via callerID data.
Now if you do use ANI, or BTN for this "lookup", you will have to query NPAC to verify who actually owns the number since it could have been ported. I would never trust a LERG 6 lookup to tell me the originating carrier.
Also, I don't "think" you can query LIDB for originating carrier information. LIDB (Line Information DataBase) is primarily used to store line options for things like if you allow collect calls, 3rd party billing, what kind of line it is (business/res), calling card numbers (I believe this is an antiquated use of the system), and sometimes the CNAM (caller name) database is coupled with LIDB (as it is with Verisign). In fact, I have access to LIDB and it wouldn't let me touch (query or otherwise) anything that isn't "me".
-Brett
Matt Klein wrote:
More specifically, see the data sheet about lidb: http://www.verisign.com/stellent/groups/public/documents/data_sheet/001944.pdf
You could go that route, or get a switch, or... there's a variety of other options. But if you're looking for a full number lookup, you're looking for lidb access..
-m
On Sun, 26 Dec 2004, Lyle Giese wrote:
That's good to get a general idea, but number portability only tells you which carrier has the block. It does not let you know about specific numbers :-{
Lyle
----- Original Message ----- From: "Matt Klein" <[EMAIL PROTECTED]>
To: "Asterisk Users Mailing List - Non-Commercial Discussion"
<[email protected]>
Sent: Sunday, December 26, 2004 5:11 PM
Subject: Re: [Asterisk-Users] OT - Originating Network identity
focus on npa-nxx (area code-prefix)
if the call is coming from a non-ported number, then http://telcodata.us/docs/queries.html may help you --
see the example files..
there are also a couple other sites out there.. but i've found this one to be my favorite thus far.
-m
On Sun, 26 Dec 2004, oi geli wrote:
I am not sure if it is the right list for the post. Please excuse my lack of expertise, if it is a bad post.
Is there anyway to detect the originating network identity of the call in Asterisk? For example, if the Asterisk gets a call from Cingular Network, is there anyway to find out that the call came from a Cingular subscriber.
Thanks
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