Tapi Ports Scaleability

[admin_2]

What is the largest number of Tapi ports currently tested per Unity/Call Manager Server combo? The CM 3.0(1) currently can support up to 2500/node, can the tapi-integrated Unity match this?<br>Thanks.<br><br>

[#2]

Hi Miguel

First, I need to make sure I understand your terminology correctly. I think you mean 2500 devices (i.e. phones), not TAPI connections. A TAPI connection corresponds to a “port” in Unity and you could never do 2500 of these (i.e. this would imply you could get 2500 simultaneous voice mail conversations going!).

Second, Cisco does not support their Call Manager being installed on a box with the voice mail server. I’m assuming when you say ‘combo’ that implies the voice mail server running on one box and the CM running on another.

Chatting with the Cisco guys, here’s the formula they use for weighting a CM install. They allocate 3000 “points” per node and weight various types of connections differently. A TAPI connection using their TAPI driver counts as 30, a phone counts as 1, a gateway counts as 4, etc… You add them all up and you shouldn’t exceed 3000 for each CM node.

OK… now I can tell you about our testing with the 2.4 version of the Cisco stuff… we were able to get 64 ports (i.e. 64 TAPI ports) running fairly comfortably with Cisco’s TAPI driver and WAV driver. This means we could handle 64 simultaneous voice mail conversations. That port configuration should easily handle a fairly large number of subscribers.

We are currently testing CM 3.0 with the “Unity TSP for Cisco Call Manager” which uses the Skinny protocol with Cisco’s WAV driver. Yeah, it’s kind of a mouthful… it’s usually referred to in house as the AVCiscoTSP for short. By comparison, the “weight” for the AVCiscoTSP is only 1 (instead of 30 for their original TAPI driver in CM 2.4). I don’t have hard numbers to throw at you yet since it’s not out of testing and I don’t want to be shooting my mouth off before we’ve covered all the bases, but it does look promising. When the load testing is complete you can be sure we’ll publish the max “ports” supported for this configuration.

Stay tuned…


Jeff Lindborg
Unity Product Architect
Active Voice Corp
jlindborg@activevoice.com

[#3]

If I remember correctly according to AV recomendations, with 64 ports you can handle about 2000 users. Which brings up my question just how many users would you recomend be supported per Unity box. Lets say that it's on the Level Two Dell 2300 with the two processors, that you guys sell. What kind of hardware would you need to handle such a load of 64 ports?

[#4]

OK… I think you have a couple of questions hidden in here. Lets see if I can get you the info you’re looking for.

I’m assuming since this question is in the IP section you’re interested in Cisco. Before I go on, I have to say we have not completed our load testing and bench marking of the new AVCisco.TSP (the TSP formerly known as “skinny”) and the new Cisco WAV driver at this point. These numbers are based on our existing product configuration information for all systems on “old school” switch equipment. The hardware requirements may be different for the specific configuration you’re looking to implement.

The first question is how many ports for how many users do we recommend. The short answer is it depends on how you’re going to be using the system. If you’re using it for auto attendant purposes (i.e. the Unity box is answering all incoming calls instead of a human) you’re going to need higher port sizes to accommodate that, of course. If you’re dealing with a DID environment where calls are forwarded to Unity on busy/RNA conditions and use of audio text is fairly light, your port limits can be lower. If your users are primarily using their desktops to get/send voice mail, you ports can go even lighter.

The old rule of thumb for a voice mail only environment was 25 users per port (which I’m sure some folks out here would argue one way or the other I suspect). If it was a heavy audio text application you’d bump that down a bit. For a primarily desktop messaging environment (say 2/3 of your folks are getting/sending most of their messages from the desktop) I’d say that could be about doubled to around 50 users per port or more.

In most cases I’d say 2000 users can be handled by 48 ports of voice if you’re in a DID setting. Of course if they’re using paging and telephone notification heavily or there’s other special considerations, you’re going to have to take that into account. Port sizing a system is more of an art than a science.

The next question is what kind of hardware is recommended for X users and Y ports. If you’re talking about 2000 users and 48 ports, the minimum we’d support (according to our Product Configuration information used by our sales support folks) is a single 500 Mz processor, 256 meg RAM and a RAID with data stripped configuration (3 drives stripped minimum, 2 mirrored). If it were me, and I wanted to make sure it performed well, I’d probably kick that up to 512 meg RAM.

This assumes fax services are handled by another server. Fax should always be run on another server if you can get away with it in my opinion but for port sizes greater than 24 we require it.

I hope that covered what you were looking for. Let me know if you were fishing for something else.


Jeff Lindborg
Unity Product Architect
Active Voice Corp
jlindborg@activevoice.com