Expand Meet-Me Conf. Capacity? 1

[Moshimoshi]

This might be a silly question - it might now. We are trying to find a way around using a costly third-party to do conference calls in house.

I've set up and dabbled with Meet-Me Vectoring and VDN, which seem to work great, but am looking at expandability if possible, can anyone field a couple of questions for me?

1. The current capacity limitation of these Meet-me conference lines is 6 members, is there a way to expand this?

2. Is there a way to see what our maximum capacity is for concurrent conference calls in the switch? Say, we have three Meet-Me conference lines, and all three are full to capacity (18 members) is there a cutoff for how many more can run concurrently before it effects the system or reaches a limitation?

3. I've heard my predecessor was seeking a conference bridge board for our existing hardware, what is this hardware, does anyone have a quick brief on how it works, or to implement it? Etc..

Any information you folks have would be greatly appreciated. This has been one of the most meaningful and helpful websites I've been able to find regarding Avaya/Definity equipment, so I really do appreciate all the help you ladies and gents give!

 

[Mitch672]

1. not without additional hardware/software. The 6 limit is a definity conferencing system limit

2. status meet-me xxxx, will show each meet-me vdn and how many calls are up. or you can status the trunk group the calls are comming in on. The cutoff is until your inbound PRI/T1 circuits are full.

3. we have setup the IP office with Voice Mail Pro as an external confernce bridge via IP trunking between the IPO and the Definity. Also, AVAYA has a low cost version of "Meeting Exchange Express" which uses SIP trunking to do a simlar thing. The Meeting Exchange Express is more flexable, and now is about the same cost as the IP Office/VM Pro solution.

Mitch


AVAYA Certified Specialist

 

[Moshimoshi]

Any guesstimate on the practical limit of 2? I would assume its a pretty reasonable number, but how can I get a look at how much space there is on the T1 for the theoretical limit?

Hope that makes sense. I'm looking for a reasonable limit for where I should cut myself off creating 6-user conference lines without choking the PRI/T1's up, and without additional hardware

 

[Mitch672]

It's not the "creation" of 6 party conferences that will fill up the PRI/T1, it's actually USING them. You could have hundred of meet-me conferences (6-party), how many are going to be used at once, it what you need to determine. How many inbound PRI/T1's do you have, and how many do you want to dedicate to meet-me conferences..

Mitch


AVAYA Certified Specialist

 

[Moshimoshi]

I think we're saying the same thing differently, I was looking for how I'd calculate the maximum concurrent-calls per trunk, theoretical - or the 'sane limit' for how many maxed out call conferences could take place at once.

However, I imagine the trunk in this case could handle a fair amount, but exec wants concrete numbers it sounds like.

 

[Moshimoshi]

So, hopefully I don't sound stupid, I'm still learning a lot of this stuff.

A regular T1 is 24 voice channels tat all work out to something like 1.54 mbps, and 1 voice channel is consumed per person on that trunk in a meet-me session

(this is done on a DID trunk, does that change things a bit?)

So if I was working on that assumption it'd be 4 conferences maxed at 6 persons all actively talking before I'd hit a capacity wall.

Lordy, I hope I don't sound stupid here, but thats what I need to know "What will kill this trunk, since we're putting these on DID lines so outside callers can use them", we're hitting $16,000+ on outserviced conference lines, so I need to know how many we can create, and if we should limit when they can be used, etc. To do that, I need to know the practical limit...make sense? Good golly I hope so.

 

[Moshimoshi]

So I can calculate the trunk limit of people calling off, I guess I just wanted to know how many people internally of the PBX could use multiple conference lines at the same time before the system bogged down, or service was effected.

Trunks are fine, I found an ErlangB calc and some formulae to throw at it, seems we're fine there

But what about internal connections to these conference lines, if six people are in one conference, and six people are in another, and yet another six people are in another, and none of them are dialing in on a DID trunk etc - whats the capacity limit.

Hahah, oh man, I don't know that I can explain the question any clearer! If no one has an answer, I'll throw an arbitrary limit out there that I think is measurably 'safe' (no more than three concurrent meet me numbers, etc)

 

[Mitch672]

THe internal callers don't afect anything, they are NOT using outside resources. Don't worry about them.

The limit is based on HOW MANY OUTSIDE TRUNKS you have on the DID range you are using. If you have 1 or 2 PRI's, that 23 or 46 channels. you don't want them all tied up with conference bridge calls, because then no one else can dial a DID and reach anyone else.

Like I said, it really can't be calculated, its based on USAGE, not how many you create. I could have a thousand 6 part conference bridges, if only 2 are in use, with 2 or 3 partys on each one, I am onlyh taking up 4 to 6 outside channels, at that time.

Mitch


AVAYA Certified Specialist

 

[Moshimoshi]

Duly noted ,and I think thats the conclusion I came for.

Figuring out line availability though, I did find this thread, which was very helpful in guesstimating Peak-call hours and line usage on our -->

http://www.avayausers.com/showthread.php?t=11401

there is also an erlang calculator at

http://www.erlang.com/calculator/erlb/

Digging in, this WAS a good indicator of usage and line availability on the DID, I took an average and then compared it against peak usage, and then made a decision from there how many DID accessible conference bridges to make.

So, despite all the babbling, I think I'm right where I need to be!

Confusing stuff though, took me a bit of brainpower to work out the line-requirement calculations.

Thanks for the help Mitch, you answered the last helpful bit of info there though, about inside-calls to the conference lines.

 

[1PhoneMan]

meeting exchange express goes for about what you are paying for outsourced conferencing, get one and dedicated T1 and you will still save thousands. get expanded meet-me and save even more!!!! I dont understand what is taking people so long to catch on. Dont sign anymore contracts for conferncing, they are locking people in because the cost for in house applications have dropped significantly.