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Ratio of Unity Ports to Unity subscribers

Is there a recommended ratio of Unity ports to Unity subscribers?? So if I have a 32 port system what will be the recommended range of subscribers that can be on the system.

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Re: Ratio of Unity Ports to Unity subscribers

Hello -

Here is a link that should help

Looks like 1599 unified messaging subscribers with off-box Exchange store. There is also a guideline mentioned in each Unity - PBX integration guide for voice ports:

The number of voice messaging ports to install depends on numerous factors, including:

- The number of calls Cisco Unity will answer when call traffic is at its peak.

- The expected length of each message that callers will record and that subscribers will listen to.

- The number of subscribers.

- The number of ports that will be set to dial out only.

- The number of calls made for message notification.

- The number of MWIs that will be activated when call traffic is at its peak.

- The number of AMIS delivery calls.

- The number of TRAP connections needed when call traffic is at its peak. (TRAP connections are used by Cisco Unity web applications and e-mail clients to play back and record over the phone.)

- It is best to install only the number of voice messaging ports that are needed so system resources are not allocated to unused ports.

We have found that many of our subscribers playback voicemail to their PC speakers, which does not require a port. For what it is worth, we are running 3.1(5) in production with 24 ports. At most, during the peak we have had 6 ports in use for 480 subscribers. We just increased our user licenses to 600, but did not increase the number of ports (server is Compaq DL380 G2 - RAID-1).

Regards, Ginger