ISDN terminals

[megglesfield]

I have a Video Conferencing terminal, that can use ISDN to set up the Video conference. Up to 4 ISDN BRI can be connected to the terminal. Each ISDN BRI is a 2B so that is 128KB for each BRI or 512Kb if all BRI are in use. I have programmed 4 BRI on an ELU28/3 and connected these via ISDN S0 addpter to the Video conferincing terminal. Question is, if I make a call from the terminal how do I use all 4 BRIs to get the maximun 512kBps bandwith? If another terminal calls mine, what extension should they call? I can establish a Video conference via the BRI but only at 64Kb. What am I missing here?

 

[singhbrindisi]

Hi,

Similar setup is in use at Brindisi ( This one had a 3 BRI interface , so 384 Kbps)& it was used for Nairobi...
May be the guys there can show some light on your requirement..

Cheers,

""The truth about action must be known and the truth of inaction also must be known; even so the truth about prohibited action must be known. For mysterious are the ways of action""

 

[dstrang1]

The call setup is done thru the codec based on the dialling string or other information requested by the dialling interface of the particular codec.

On a bonded call, the call is established on the first channel, then the far end codec will typically respond back with the numbers to be dialled for the subsequent channels.

As far as what you need to enter in the dialling interface when placing a call, it depends on the codec. If you have a Polycom, you enter the destination digits and select the line speed in a drop-down box.......the Polycom will send the entered digits out thru each channel individually (think of a 384kps call as 6 separate phone calls).

If you have to dial thru an IMUX or a gateway, you may need additional prefixes or suffixes which define the channel speed (56k or 64k, the number of channels, and an IMUX code.

ex. 443109908*64*6*8 == this would be the dial string for a call to 443109908 specifying 64k line speed, 6 channels (384kbps) and the call is a bonded call.

Internally, you can set the div. pt. for your IT extensions to roll to each other so an inbound caller needs to only dial the first extension number.

Good luck,

Dave Strang