[asterisk-users] Best practise for ISDN Video Conferencing..

[Vinícius Fontes]

----- "Mark Adams" <mark at campbell-lange.net> escreveu:

> Hi, thanks for your response.
> 
> I'm not sure if I explained correctly. I need asterisk to provide an
> ISDN data function, whilst also routing voice calls over the same PRI.
> Is this possible?
> 
> Regards,
> Mark
> 
> On 3 Mar 2010, at 17:58, Vinícius Fontes <vinicius at canall.com.br>
> wrote:
> 
> > ----- "Mark Adams" <mark at campbell-lange.net> escreveu:
> >
> >> Hi All,
> >>
> >> I'm about to setup an Asterisk install to take over an old legacy
> PBX
> >> system. At present, the legacy system has modules in it which
> >> provides
> >> 4
> >> * data ISDN links to the video conferencing unit (Tandberg 3000
> MXP)
> >> on
> >> site, these use the ISDN30 (uk) that the normal voice calls go
> over.
> >>
> >> Is it possible to emulate this in asterisk? I've seen zapras but
> I'm
> >> not
> >> sure if that's right.
> >>
> >> Is there a better way to do Video conferencing over ISDN in
> asterisk
> >> that will work with the Tandberg unit?
> >>
> >> Thanks,
> >> Mark
> >>
> >
> > I don't think Asterisk can do video over ISDN. It would be great if
> > anyone can prove me wrong thought.
> >
> > --

I understood it perfectly, I guess. You probably have an ISDN videoconferencing product attached to a proprietary PBX (like Siemens, Ericsson, etc). When you make a videoconference call, the Tandberd connects to the PBX, requests X ISDN channels (depends on the video quality you want) and transmits the audio and video as data using the ISDN channels.

Unfortunely I'm almost sure Asterisk doesn't supports this. As far as I know, you can only send audio on ISDN channels. There is a VIDEO transfer capability implemented on the CHANNEL function, but I'm not sure if that works at all:

pabx:/home/vinicius# asterisk -rx "core show function CHANNEL"

  -= Info about function 'CHANNEL' =- 

[Syntax]
CHANNEL(item)

[Synopsis]
Gets/sets various pieces of information about the channel.

[Description]
Gets/set various pieces of information about the channel.
Standard items (provided by all channel technologies) are:

(snip)

R/W	transfercapability ISDN transfer capability (one of SPEECH, DIGITAL,
                          RESTRICTED_DIGITAL, 3K1AUDIO, DIGITAL_W_TONES, or VIDEO).



Maybe that could be a start, but unfortunely I have never dealt with a situation like that before.