First, it is a good idea to get a handle on the differences between the various types of messaging Cisco provides in their portfolio.  There is Unified Messaging, Voicemail Only, and Integrated Messaging.  My colleague David Hailey did a write up on UM vs. Integrated Messaging here:

http://www.netcraftsmen.net/resources/blogs/integrated-messaging-vs-unified-messaging.html

Unity Connection throws in a few nifty features that revolve around the concept of relaying messages to foreign message stores.  I did a write up on voicemail only, integrated messaging, and relay functionality with Unity Connection here:

http://www.netcraftsmen.net/resources/blogs/voicemail-only-voicemail-relay-and-integrated-messaging-options-with-unity-connection.html

To answer your questions more directly:

dabellan wrote:
 
Unity connection is a Voice Mail solution and it does not integrate with Lotus, the only possible integration is when you configure IMAP, but it does not depend on the mail server (Exchage or Microsot). Isn't it?

Unity Connection supports: voicemail only and integrated messaging

As the message store provider, Unity Connection can host IMAP connections from IMAP and IMAP-Idle compliant clients.  Whether it is Lotus Notes, Outlook, CUPC, etc.  Integration guides and testing/resources focus on Outlook and Lotus Notes, but I have pulled e-mail via other IMAP clients.  A key design consideration is whether the client being used can support IMAP-Idle or not.  The basic idea is that IMAP-idle allows a client to subscriber to a mailbox and the server will push to the client.  Versus the opposite model where the client is constantly nagging the server to see if there is a message available.  The latter approach is more resource intensive and, therefore, reduces your overall maximum capacity for IMAP client connections.  By a factor of 4 times.  Outlook supports IMAP-idle.  Lotus Notes does not.  Which means you need to get creative or accept a reduced capacity (for concurrent client connections - key point).

There is a flip side to the coin that some people overlook.  Unity Connection tries to "unify" the experience by reading calendars and e-mail from an external message store.  The idea is that using IMAP from a client like outlook is "unifying" the GUI, but there should be a solution to "unify" the telephone user interface (TUI) as well.  To do this, Unity Connection becomes an IMAP client and retreives e-mail headers from the corporate e-mail message store.  Documentation suggests this is only viable with Exchange.  But I have not tested this myself.  Further, calendar integration (allowing appointments to be announced over TUI) is only supported with Exchange.

dabellan wrote:
 
Unity is a Unified Messaging solution and in this case it integrate the mail box with Exchange of Lotus. I this case it make sense to chosse between Domino and Exchange. Isn't it?

Unity supports: voicemail only, integrated messaging, unified messaging.  Unity supported integrated messaging because Unity Connection was not conceived at the time the customer demand needed an integrated messaging solution.  I believe that Cisco called it Unified Mailbox or something equally as cute at the time.  Whatever the history, today Unity is Cisco's only Unified Messaging product.  In all of our deployments we only leverage Unity if Unified Messaging is a requirement.  In all other cases, we use Unity Connection.  I believe that this is a trend with several partners.

Up to and including release 7 of Unity, you can integrate with Exchange or Domino.  After release 7, support for Domino is dropped.

I think I covered everything.  If not, I am sure my friend Hailey will let me know.  In either case, he will pipe in I am sure.

HTH.

Regards,
Bill

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