[asterisk-users] UK FXO hangup detection with a twist

[David Boyd]

On Mon, 2008-03-31 at 16:25 +0100, Steve Davies wrote:
> On 31/03/2008, Mike Dent <mcdent at gmail.com> wrote:
> >
> > On 31/03/2008, Steve Davies <davies147 at gmail.com> wrote:
> > >
> > > The twist? We actually have far-end hangup detection working fine, and
> > > that seems to be where the problem lies for most people. Our problem
> > > seems to be with requesting a hangup from our end reliably.
> > >
> > > If we originate the call, we can hang it up. This suggests to me that
> > > the Sangoma A200D is sending the correct hangup signaling. This way
> > > round, it is 100% reliable.
> > >
> > > If we accept a call originated elsewhere, then we cannot hang it up.
> > > Only the call originator seems to be able to do that. The upshot is
> > > that if asterisk hangs-up a line, and then tries to re-use it for an
> > > outbound call before the remote has disconnected, we are simply
> > > re-connected to the original caller, and start to play DTMF at them!
> > >
> > > Has anyone experienced this before? Anyone found a solution?
> >
> >
> > People regularly use this feature to answer a call, then decide they need to
> > run upstairs to speak etc, so they put
> > the receiver down, go upstairs (or wherever) and pick up the handset to
> > speak. It dates back many years and I  should think is designed in to the
> > system in the UK. Not sure on modern exchanges how long it would take for
> > the
> > line to clear.
> >
> 
> I do the same myself, but for PABX use, that feature must be fatal!
> The line clearing time is long... I waited a couple of minutes at
> least. Is it possible to turn it off (call BT and ask for a certain
> feature to be enabled/disabled) or to shorten the line-clearing time
> to zero? Or perhaps Asterisk is able to detect the line state or the
> dialtone and act correctly to avoid re-using an open channel.
> 
> In fact, the "obvious" way to do this might be if Asterisk could set
> the channel state to "hanging up" and wait for the far end signal
> (loop disconnect) that the line has actually been disconnected.
> 
> This is a bit of Zaptel that I've never looked at, so I have no clue
> if what I am suggesting is even slightly possible.
> 
> Steve
> 
> _______________________________________________
> -- Bandwidth and Colocation Provided by http://www.api-digital.com --
> 
> asterisk-users mailing list
> To UNSUBSCRIBE or update options visit:
>    http://lists.digium.com/mailman/listinfo/asterisk-users



You should ask for ground start signaling. This will resolve your
issues.

Dave