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ratio of user to ports

Is there any kind of formula/documentation for how many Unity ports are needed to how many users? I have a customer who is asking for some kind of documentation on this.<br><br>


Re: ratio of user to ports

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… there’s no hard and fast formula I can give you that will work for all sites. Some dealers will come back to a site after it’s been in use for a month or so and run port usage reports to see if more ports are necessary based on how the site is using the system (for whatever reason it never seems to result in FEWER ports… I don’t know why that would be ;->). This is not a bad strategy to take…

Jeff Lindborg
Unity Product Architect
Active Voice