CNAM not showing up at the called party

I am trying to wrap my head around this. I have a Freepbx Distro 2.11 with CallerID Management module installed. I can send two different numbers out at will, no problem. The CallerID name does not follow. Using a TCPdump I can see that the call is setup with both the correct CNAM and the CID being sent to the SIP trunk provider. Actually I have two providers. One is ESI and the other is Clear Rate. Both are sending the same info to my cell phone. Are they responsible for passing Both CNAM and CID to the called party?

Hey Ed,

I’m a bit of a noob with this stuff but I’ve got an okay understanding of things, and I believe that you’re half right here. BOTH endpoints of the call need to be provided with this information by the carriers. SIP doesn’t care, it’s a protocol. A carrier might, because people could put something that would endanger, harass, or defraud the callee.

Off the top of my head:

  • 911 Operator
  • US Government
  • Microsoft/Apple Tech Support
  • VISA/Mastercard
  • [Bank Name Here]

So rather than put themselves at risk of liability for transmitting falsified data, and for the good of the general public, they likely drop it.

I don’t know any of this for sure, but as a thought experiment I think it works :slight_smile:

It would be the cell phone carrier that provides the CNAM “dip” it would display, thus unlikely to work :slight_smile:

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Thanks guys for the replies. I pretty much figured what you both said. Chalk it up to another Gotcha for the industry then. IMHO it seems like the calling phone carrier should have the control not the called phone carrier. Ass backwards it seems to me. But hey they didn’t ask me :))

I think they usually ask people then do the opposite of whatever they say :smiley:

The calling phone carrier DOES have control over it, it’s just that it is VERY expensive to subscribe to and maintain, so many budget VSP’s just don’t spend that money.

Dicko— I guess that is why they charge per month to add it to the account then. Information is only as good as what is paid to get it huh? We decided to wait some time to see if the name propogates through the “system”.

Overkill – You are definitely right about that sometimes!!! LOL

Again Thanks guys. Have a good holiday season!

You’re welcome! Merry PBXmas™! :wink:

Just to clarify this…

FreePBX configures Asterisk to send both Caller ID Number and the Caller ID Name (“CNAM”) that you specify. However, in the U.S. most carriers dump the CNAM that you send, and then use the Caller ID Number to lookup the correct name from a database. Looking up names in the database usually costs money (a fraction of a cent), so some VOIP carriers won’t use the database or offer you the option to use it or not. All major carriers (AT&T/Verizon/etc) and (I think) all wireless providers consult the database for inbound CNAM.

Some carriers can update this database for you if you want to change what appears. Some carriers charge a fee to update the database with new information ( charges $10.00 and you have to open a trouble ticket) and some do it for free (Flowroute let’s you do it via the web portal and AT&T does it automatically when you sign up).

Not to be argumentative, but there is no one authoritative “the database” anymore there used to be CNAM and LERG, now there is CNAM for landlines and CNAP for Cellphones and further market driven costs to supply that have precluded any likely agreement any day soon. To see the greed :-

and of course

Given the near 1000000 changes a day and the multi thousand dollar a month cost to join those clubs, few CLECS or lower will pay for or administer that, so you are kind of drifting in the wind if you want any Mobile carriers to honor your paid for but generally outdated/ignored requested “CNAM” in any timely fashion.

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So basically it sure isn’t like the “old” days of Pots lines. You get what you get, or what you pay for.

Thanks guys for all the info. Have a great Christmas and a Happy New Year!