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VPIM vs Digital Networking, which is best for Unity VM?

Hi All,

I need to network a pair of Unity VM only boxes. They are at different physical locations, and are integrated with 2 different CCM clusters. They both have the message store located "On the Box", with Exchange 2000 and 2003. Right now, they are in different domains, but that could be changed so they are in the same domain.

My question is: What's the best method for networking these together? The Unity Networking Guide tells me how to do it, but not why one is better than another. Does VPIM offer any advantage if both servers are in the same domain?

Thanks, Randy


Re: VPIM vs Digital Networking, which is best for Unity VM?

Hi Randy -

For digital networking between two Unity servers, they don't need to be in the same domain, just the same AD forest. Digital networking does not require AD schema updates, a voice connector, or licensing update. VPIM networking requires a voice connector to be installed as well as AD schema updates and a license update. And it is used primarily to network non-like Unity systems (i.e. Unity/Exchange to Unity/Domino; Unity to Unity Express; Unity servers in different AD forests etc.). Additionally with digital networking, you can purchase a licence update (about the cost of one VM-user per server) that enables License Pooling. Here is an excerpt from the doc -

"Though you do not need a license for Digital Networking, you may want to add a licensed feature called license pooling. License pooling allows Cisco Unity servers that are set up for Digital Networking to pool licenses for subscribers and for the Cisco Unity Inbox. With license pooling, if total utilization across all of the Cisco Unity servers does not exceed total licenses for the feature, the Cisco Unity server is in compliance with licensing restrictions. For example, suppose two Cisco Unity servers each have 500 licenses for subscribers. With license pooling, one of the servers can use 501 or more licenses as long as the total used by both servers does not exceed 1,000." There are other advantages to having your Unity servers digitally networked - here is a link of features we have implemented -


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