[Asterisk-Users] Ring more than two isdn phones simultaneously

[Arik Funke]

In your opinion, is there any chance that this situation will change in 
forseable future? Is anybody already working on such a "pseudo-channel" 
structure required for decoupling asterisk channels from the physical 
channels? If not, is there a significant interest in the asterisk 
community to do this?

Arik


Peter Svensson wrote:
> On Sun, 21 Aug 2005, Arik Funke wrote:
> 
> 
>>If this is a limitation of asterisk, where is it located? In the 
>>chan_zap module? In zaphfc? I.e. would it help if I switched to mISDN?
> 
> 
> It is inherent in the channel-based structure of Asterisk. An audio 
> channel is the basic measure used by applications such as Dial etc. This 
> is shared by all channels as far as I know. 
> 
> One can imagine a special version of chan_zap that decouples the Asterisk 
> channel entities from the actual B-channels. It would always generate a 
> new fictitious asterisk channel structure and only link it to a real 
> B-channel once the signaling indicated that a B-channel was required. 
> 
> I would be interested in how the commercial SS7 implementation for Asterisk 
> works. SS7 would normally allow the audio paths to change in mid-call to 
> potentially follow an altogether different route.
> 
> Peter
> 
> 
> 
>>Peter Svensson <psvasterisk at psv.nu> wrote:
>>
>>On Sat, 20 Aug 2005, Nico Giefing wrote:
>>
>> >> how many connection do you have from your asterisk to the old pbx?
>> >>
>> >> i think on 1 ISDN connection its only possible to let 2 phones ring, 
>>because
>> >> 1 ISDN 2 channels...
>>
>>
>>This is a limitation in Asterisk, not ISDN. Asterisk reserves a B-channel
>>for each destination at the time of the CONNECT message. In the isdn world
>>it is common to not actually allocate a B-channel until it is needed to
>>carry audio. This also prevents Asterisk from letting the upstream switch
>>select the B-channel on outgoing calls to the pstn.
>>
>>Asterisk is written this way since it uses the audio channel as the
>>fundamental unit, with the D-channel as carrier of signalling for the
>>individual B-channels. Another way to view ISDN is to consider the
>>D-channel the fundamental unit, which can carry several audio streams as a
>>side effect of the signalling. The first viewpoint resembles the
>>traditional view of telephony as individual circuits, the second resembles
>>the ISDN/SS7 view of the world.
>>
>>Changing Asterisk to be more ISDN-like is quite a lot of work.
>>
>>Peter
>>
>>
>> >>
>> >> ----- Original Message -----
>> >> From: "Arik Funke" <arik.funke at gmx.de>
>> >> To: <asterisk-users at lists.digium.com>
>> >> Sent: Saturday, August 20, 2005 7:44 PM
>> >> Subject: [Asterisk-Users] Ring more than two isdn phones simultaneously
>> >>
>> >>
>> >
>> >>> > I am using a HFC-S card in nt mode with zaphfc driver to connect an
>> >>> > internal isdn bus. I would like to signal an incoming call on, let's
>> >>> > say, 4 phones. Right now I use:
>> >>> >
>> >>> > Dial(Zap/g1/21&Zap/g1/22&Zap/g1/24&Zap/g1/23&Zap/g1/29,,t)
>> >>> >
>> >>> > where g1 are my two isdn channels provided by HFC-S card an the
>> >>> > 21,22,etc my internal numbers.
>> >>> >
>> >>> > When the command is executed however, only the first two specified
>> >>> > phones ring. Etc. with the first channel 21 ist called, with the 
>>second
>> >>> > 22. How can I get asterisk to signal to all phones with just one isdn
>> >>> > channel? I am trying to duplicate the setup I had with my old 
>>isdn pbx
>> >>> > with did above trick just fine... Maybe somebody can help me 
>>configure
>> >>> > asterisk appropriately?
>> >>> >
>> >>> > Cheers,
>> >>> > Arik
>> >>> >
>> >>> >
>> >>> > PS: I gave following a try but without success:
>> >>> > Dial(Zap/g1/21-29,,t)
>> >>> > Dial(Zap/g1/21+29,,t)
>> >>> > _______________________________________________
>> >>> > Asterisk-Users mailing list
>> >>> > Asterisk-Users at lists.digium.com
>> >>> > http://lists.digium.com/mailman/listinfo/asterisk-users
>> >>> > To UNSUBSCRIBE or update options visit:
>> >>> >    http://lists.digium.com/mailman/listinfo/asterisk-users
>> >>> >
>> >
>> >>
>> >> _______________________________________________
>> >> Asterisk-Users mailing list
>> >> Asterisk-Users at lists.digium.com
>> >> http://lists.digium.com/mailman/listinfo/asterisk-users
>> >> To UNSUBSCRIBE or update options visit:
>> >>    http://lists.digium.com/mailman/listinfo/asterisk-users
>> >>
>>
>>
>>Peter
> 
> 
>