Exchange 2010 Unified Messaging : PART 1

Unified Messaging offers extra end-user functionality

Call Answering
Outlook Voice Access (OVA)
Access to Email, Voicemail, Calendar, Contacts & GAL
Auto Attendants
Speech-to-text / Voicemail preview
One of the big changes compared to Exchange 2007 UM is that MP3 audio codec has been added to provide better support for Blackberry and iPhones.

Storage of Voicemail messages

Voice mail messages are stored like normal messages in the mailbox of the user. In practice, we see a mailbox storage increase of about 20% when using unified messaging. Voice mail is not stored on the UM server itself because the UM server primarily does the conversion of voice mail to a message and vice versa.

Hardware requirements

The Unified Messaging Exchange role can be processor intensive. It is not especially I/O intensive.
Since the release of Exchange 2010 SP1 it is possible to virtualize the UM server role using Hyper-V or VMWare. The virtual machine should have the following requirements :

Minimum 4 cores X64 bit processor. This requirement affects the ability of the Unified Messaging role virtual machine to utilize physical processor resources. UM significantly benefits of multiple processors.
16 GB memory recommended (16 GB is required in order to get Microsoft support )
+/- 1,5 GB storage required for exchange program files (Exchange UM role + 500 MB / language pack)
Storage for queuing voice mail messages when a HUB server is temporarily offline. ( voice mail messages take approx. 100 KB each.
1 Gbps Network Interface

Software requirements

Windows Server 2008 x64 Standard R2
Exchange prerequisites
- .NET framework 3.5
- Windows Powershell 2.0
- WinRM 2.0
- Extensions for ASP.NET AJAX 1.0
- Desktop experience operating system feature
- MMC 3.0
Exchange Server 2010 Standard SP1
- Exchange 2010 Update rollup 3