[VoIP] Questions about payphones (was Re: CAMA and UK billing)

[Donald Froula]

These references are helpful, but probably don't have
enough technical detail to implement the software.
They do have correct references to the
Bellcore/Telcordia specs. I could probably get copies
of the standards from my company's tech library. 

Neat project!

http://www.att.com/Large-Files/RIMS/Network_Interface_Specifications/AM-TR-NIS-000095.pdf

http://www.att.com/Large-Files/RIMS/Network_Interface_Specifications/AM-TR-NIS-000103.pdf

Regards,

Don

--- Mark Rudholm <mark at rudholm.com> wrote:

> Jayson Smith wrote:
> 
> >      So what you're saying is, a standard
> four-wire phone cord would do the
> > trick as far as all phone service and coin relay
> control is concerned? So
> > could I have him just run a four-wire modular jack
> or plug, connecting all
> > relevant wires, and have all my bases covered?
> 
> Yes.  When in real service, these phones are
> connected to Tip and
> Ring from the CO, and a local earth ground.  This
> way, they are able
> to operate on a single wire pair, just like any
> other phone.
> 
> They're quite easy to wire up yourself.  Just buy a
> modular cord
> that has spade lug terminals on one end.  The
> terminals are clearly
> marked "T", "R", and "G", which correspond to Green,
> Red, and
> Yellow, respectively.  But I suppose Phil can do
> that for you if
> you're buying a phone from him.
> 
> >      That's what I thought about initial deposit.
> So, have him set that to
> > five cents, so it never becomes an issue.
> 
> Yep.  Again, this isn't hard to do yourself.
> 
> >      How are you thinking of pulling this off in
> software? Will there be a
> > configuration file with rates and time limits
> specified? Or will an
> > extension need to call an application and specify
> what rate to charge for
> > how long, and if no application call is ever made,
> the call is free?
> 
> I don't intend for this to be a commercially useful
> project.  To
> be commercially useful, you'd want to take an
> entirely different
> approach --like out-of-band coin deposit and control
> signaling
> within the IAX2 or SIP protocol itself, not in-band
> tones.  One
> wouldn't want to repeat the mistakes of Ma Bell :)
> 
> I haven't addressed the software configuration issue
> yet.  DTMF
> and MF decoding is done in dsp.c via some simple
> goertzel analyses.
> What I had in mind was to add a fifth row and column
> to the DTMF
> tone set for 1700 and 2200Hz.  This would basically
> give me another
> "digit" to use in the dialplan.  Coin return/collect
> would be
> handled with a shell or PERL script called via AGI. 
> I was planning
> on relying on the functions of features.conf to give
> me the
> ability to detect "buttons" in-call ("buttons" in
> this case
> would be the 1700+2200Hz coin tones).  Beyond that,
> I haven't
> solved it...
> 
> Ultimately, I would be able to publish a schematic,
> some assembly
> instructions, a patch set for Asterisk, as well as
> some
> instructions and examples of how to write the conf
> files.
> _______________________________________________
> VoIP mailing list
> VoIP at lists.ckts.info
> http://lists.ckts.info/mailman/listinfo/voip
> Project Web Page: http://www.ckts.info/
>