[Asterisk-Users] CallerID Name problem

[Damon Estep]

The CDR is written at the end of the call, the SIP invite is generated when you tell it to.

You must wait for the CID name before you "dial" a SIP channel, as this is when the SIP invite is created.

Wait 1 seems to be long enough.

For analog TDM this is not an issue as the CNAM is sent between the first and second ring.

In nearly every case I have seen, the facility IE that contains the CNAM on most NI-2 ISDN PRIs, the Facility IE is not sent until after you send progress back to the telco.

Like this;

Telco sends ISDN SETUP message
You send back ISDN PROGRESS (on a normal call)
The Telco sends ISDN FACILITY INFORMATION ELEMENT (IE) containing CNAM

I have looked at several protocol monitoring session form both Nortel and lucent class 5 switches, and every one seems to send the facility IE in less than 500 milliseconds following SETUP assuming you (Zaptel) reply PROGRESS in a timely fashion, which does not appear to ever be an issue with Asterisk.

I have been lead to believe there are two reasons for sending the CNAM in the facility IE.

One explanation is that the SETUP message has a restriction on length, and in order to provide other features, the CNAM had to be moved.

The other explanation is that the Telco is saving costs by not dipping into LIDB (line information databases) for all calls where PROGRESS is not received from the endpoint (a high percentage of all calls). There is a cost associated with LIDB dips.

Both are believable explanations, but the result is the same, you have to wait 1 second!

Sure would be nice if asterisk could wait 500 milliseconds instead, since there is a need to put a "play 1 second of silence" in the first step of the IVR (if used) to avoid clipping the first phrase also. The combined 2 seconds of "wait" gets noticed by some users/callers.

For the archives - The Lucent TNT (as of 11.0 firmware) is not capable of "waiting" for CNAM before generating the SIP invite, so it is not compatible with PRIs where the CNAM is sent in the facility IE instead of the SETUP message, which is the case with most telco switches with current software on them.

Damon












> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-
> bounces at lists.digium.com] On Behalf Of Josh McAllister
> Sent: Monday, May 01, 2006 4:25 PM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: RE: [Asterisk-Users] CallerID Name problem
> 
> 
> >From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-
> bounces at lists.digium.com] On Behalf Of Lacy Moore - Aspendora
> >Sent: Monday, May 01, 2006 3:06 PM
> >To: Asterisk Users Mailing List - Non-Commercial Discussion
> >Subject: Re: [Asterisk-Users] CallerID Name problem
> >
> >Do you get caller ID number?  If so, WAITing is not going to help, since
> you already get the info.  If you >get caller ID number, then your telco
> is not >sending the name.
> 
> This is not necessarily true. I've always gotten cID number, but only
> recently when I added a wait(1) did I start getting channel vars populated
> with cID Name. Same as Eric, I was getting cID Name in the CDR records all
> along as well.
> 
> Eric -- Go ahead and give it a shot... even if you are getting the cID
> number. This will likely fix your problem.
> 
> Josh McAllister
> 
> 
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