MGC Cascading

[MarvinK]

My group is using a Polycom MGC-100 and we plan to bring in over 20 ISDN sites. Anyone got any advice on how I should go about this?

[mazzarak]

I'm assuming you have room on your bridge for this...

Also, assuming you know what speed they all run at, simply create two calls. The first call will contain half your sites (for arguments sake) and an extra site which you'd call "cascade out". The second call will contain the other half of the sites, and an extra site called "cascade in". When this is set to dial in, you'll get a DNIS number to dial into. Put this number in the Dial out Profile of the other site.

Assuming quite a lot there, drop me a line if you want any further tips.

[Entropy3XD]

Originally posted by MarvinK@May 20 2004, 12:27 AM
My group is using a Polycom MGC-100 and we plan to bring in over 20 ISDN sites. Anyone got any advice on how I should go about this?
What do you have for hardware on your Accord? What kind of blades?

[MarvinK]

Thanks mazzarak,

I'll utilize the advise you presented and let you know how it works out.

[tjulian]

I'm confused....

If you have the capacity (net and mux resources) on one bridge, why do you need to create two different calls. Can't you just put all 20 in the same call?

I admit, my MGC-100 is a "bare-bones" system with a max of only 8 endpoints, but is there some upper limit to the number of participants in a call?

Oh, yeah, and the best advice I can give you about trying to connect 20 ISDN endpoints at the same time: don't...:D

[mazzarak]

there is a limit to the number of ISDN sites you can have in a call. I think this has something to do with calls covering more than one card though I can never remember which card it is.

With a CP call you can only get 12 video sites, but with Video Switching you can reach 16.

Anyway, connecting 20 sites at once is a doddle ;)

[MACC the AVCOtek]

Originally posted by mazzarak@May 24 2004, 04:11 PM
Anyway, connecting 20 sites at once is a doddle ;)
What a cool site! Where else can you hear the word 'doddle' used in an actual sentence!? B)


Uh, I looked up 'doddle' at this site (http://www.peevish.uk.com/slang) and it said that doddle means 'An easy task.' Is this correct, mazzarak?

[mazzarak]

Yep. Like a walk in the park...

I shall do my best to bring a bit of british best to the forum in future for your entertainment and amusement :rolleyes:

[tjulian]

Originally posted by mazzarak@May 24 2004, 10:11 AM
there is a limit to the number of ISDN sites you can have in a call. I think this has something to do with calls covering more than one card though I can never remember which card it is.

With a CP call you can only get 12 video sites, but with Video Switching you can reach 16.
Ahhh, yes, I think I remeber reading that somewhere...once...a long time ago :D

Thanks.

[MACC the AVCOtek]

Originally posted by mazzarak@May 25 2004, 09:38 AM
I shall do my best to bring a bit of british best to the forum in future for your entertainment and amusement :rolleyes:
And I shall do my best to throw in a few Hawaiian words here and there.... Even exchange, eh? :D

[shailandra]

Hi I am new for this community... :rolleyes:

I saw a solution of cascading but that will result in to confusion as I am afraid you will not be able to recognize the participants of cascaded window...let us see an example with one card if we connect 11 locations then cascaded connection will be our 12th window having remainning 9 locations in which you will not be able to recognize who is who...pls correct if I am wrong. :o

[mazzarak]

this is true, but calls with that many sites are usually not that interactive. If we had 20 sites on a meeting, its usually for a presentation of some kind. We'd have the presenter in one call, then create 4 cascades in Hollywood squares. Then the four cascade meetings would be voiceactivated, lecture mode, with the cascade port as the lecturer. Then set the rotation for those sites to, say 7 seconds (four times, for four meetings).

net affect: presenter site sees hollywood squares rotating through the sites that are connected.

Besides, if you have a call that big, its a miracle for some users to remember which site is which, even when they CAN see them all :)

[Video_Man]

Hi there!!!! This is Video Man new to this Video conferencing World and am 3 months old in this field ,i agree totally to everyone's view about cascading conferences to be a utility in case of presentations to a wide number of loations which can be kept in LECTURE MODE and the same sites rorated so that the presenter can see each one of them one by one.Correct me if i am wrong ,so far this is my contribution from my side dudes.Keep on posting new questions so that we can open up a R&D centre for these VIdeo Conferencing Companies :D

[Samoht]

Yes, I agree to the comments on cascading and large conferences :o and there are limitations with the old H/W in the MGC :( , which I believe is used in this scenario.
However, it is possible to run a single conference in voice switched mode with up to 30 participants with the old audio module (s). Of course you need to have enough ressources. In your case at least two audio 12 modules. You need to reconfigure the audio bridge chip on the first audio module to run 1x30 instead of the default 4x16 configuration. This will allow internal expansion of the audio module management to support up to 30 participants from this one audio bridge, even if the participants are connected to up to three different audio cards.

Tom

[zinman]

What you need are at least 24 ports of Video Card capacity and enough IMUX ports. What to do is create a 2 conferences, dial out of one and into the the other with the Accord (sort of an internal cascade). The other advise I would give is to force H.261 and CIF to force everyone to a simple compatible algorithm. This will allow you to have a confernce which includes up to 22 sites (24 less the 2 used for the internal cascade) of H.320 or mixed H.320/H.323 sites.