[asterisk-users] Hang up detection with TDM400P and Telewest/Virgin Media line

[Gordon Henderson]

On Mon, 13 Oct 2008, Mike wrote:

> On Sun, Oct 12, 2008 at 11:18:40AM +0100, Gordon Henderson wrote:
>> On Thu, 9 Oct 2008, Mike wrote:
>>
>> I'm guessing this lamp is on an ordinary analogue phone you have?
>>
>
> Yeah, this is a bog standard 9 quid analogue phone.
>
>>
>> OK. A bit convoluted this as I'm not local to the PBX, but an IAX trunk,
>> another asterisk and a SIP phone away from it - however I'm looking at
>> verbose console output on the original asterisk box which has an OpenVox
>> card (TDM400 clone) so:
>>
>> Telewest line <-> TDM <-> Asterisk <-> IAX trunk <-> Asterisk <-> SIP phone
>>
>> I call into the site on their Telewest landline from my mobile (O2). My
>> phone rings, which is to be expected.
>>
>> I don't answer it, but hangup my mobile.
>>
>> I can't tell if telewest have dropped the line immediately, but from
>> asterisk point of view, the line stays "open" for about another 2-3
>> seconds, then hangs up and asterisk detects it and stops the phone
>> ringing. As far as I can tell, this is all perfectly normal, and it's what
>> I see with BT lines too.
>>
>> If I answer it, that's fine too.
>>
>> If I then hangup the mobile, the (analogue) line hangs up almost
>> immediately, this is detected almost immediately by asterisk and it clears
>> down the call.
>>
>> So that's more or less what I'm expecting.
>>
>> Going the other way: Dialled out from my SIP phone to my mobile - when I
>> hungup the mobile the call dropped almost instantly and my SIP phone
>> hungup.
>>
>> So again, that's more or less what I expect.
>>
>
> Thanks for doing that.  Do you mind showing me your zapata.conf?


/etc/zaptel.conf (just for completeness):

   fxsks=3
   fxsks=4
   loadzone=uk
   defaultzone=uk

zapata.conf:

   [trunkgroups]

   [channels]

   ; Default settings applicable to all channels

   usecallerid=yes
   cidsignalling=v23
   cidstart=polarity
   hidecallerid=no
   callwaiting=no
   threewaycalling=yes
   transfer=yes
   echocancel=256
   ;echocancel=yes
   ;echotraining=yes
   echocancelwhenbridged=no
   immediate=no
   faxdetect=no

   ; Channel 3: PSTN line
   context=incoming
   group=1
   usecallerid=no
   faxdetect=none
   signalling=fxs_ks
   rxgain=4
   txgain=4
   callerid=asreceived
   channel => 3

   ; Channel 4: PSTN line
   context=incoming
   group=1
   usecallerid=no
   faxdetect=none
   signalling=fxs_ks
   rxgain=4
   txgain=4
   callerid=asreceived
   channel => 4


>> I've heard that Telewest used whatever switch they could get their hands
>> on at the time when they were building their network, and that different
>> regions might well have different equipment in the TW exchanges. More
>> complicated by them buying up the local cable co's (eg. Eurobell in the
>> Plymouth area where this line is), then being sucked into the ntl: monster
>> and now virgin media.
>
> Yeah, I gather all the many, small telcos doing cable all eventually
> merged together.  I'm trying to get hold of a Telewest engineer to find
> out what is going on.  Naturally this is proving challenging...

Again, good luck - you might need it after the last round of 
renaming/merging from TW to ntl: and now Virgin Media..

Gordon