A Guide on Unified Messaging in Exchange Server 2007

Bringing geographically dispersed workforce together in virtual environments to collaborate on tasks is a challenge addressed by the productivity and collaboration features of Exchange Server 2007.

The exchange server deployed in the Unified Messaging role enables PBX integration (regular and VoIP services) to allow voicemail and fax messages delivered to exchange mailboxes. It also provides IVR (interactive voice response) dial-in capabilities directly to the exchange server.

So here’s a step-by-step guide on how to integrate the unified messaging server into your phone system. But please note: this how-to guide only describes the server configuration tasks — not the hardware and wiring requirements.

The dial plan is the central component of the UM system as it represents the extension groups within the phone system and is a logical representation of the PBX dial plan. You can configure a single dial plan or have multiple dial plans that represent different extension groups.

Users that belong to the same dial plan will each have a unique extension that identifies their phone. And users within the extension group will be able to call each other using only the target users extension.

The dial plan also allows you to configure unique sets of features and policies for each extension group. Note that for each dial plan created, a default UM mailbox policy will be created.

You can create a new dial plan using the exchange management console:

  1. Select Organization Configuration
  2. Select Unified Messaging
  3. Under actions select create new UM plan
  4. Give the plan a unique name
  5. Assign the number of digits for the extension (usually 3)
  6. Click finish

You can create a new dial plan using the exchange management shell:

new-UMDialPlan -Name:'assignnameDilaPlan'  -NumberOfDigitsInExtension:'3'  -AccessTelephoneNumbers '123'

Dial Plan

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The organization’s PBX must interface digitally to the messaging network. This is done via the VoIP gateway or an IP-Private Branch eXchange (PBX), that is enabled for Session Initiation Protocol (SIP). The gateway must be configured for each Dial Plan using either the management console or the shell.

You can create a new UM IP Gateway using the management console:

  1. Select the Organization Configuration
  2. Select Unified Messaging
  3. Select the UM IP Gateway tab
  4. Click New UM IP Gateway
  5. Enter a unique UM IP Gateway Name
  6. Enter either the IP address of the gateway or a fully qualified domain name
  7. Click finish

You can also create a new UM IP Gateway using the exchange management shell:

new-UMIPGateway -Name:'sipXServer'  -Address:'sipX.lithnet.local'  -UMDialPlan:'3DigitDialPlan'

If you use a FQDN, you must add the appropriate records to the DNS zone. Also, if the gateway will be associated with a dial plan that is operating in secure mode, you must use a FQDN and not an IP address. It is recommended that you use a FQDN rather than an IP address, as IP addresses tend to break functionality.

The UM Mailbox Policies

Mailbox policies set restrictions and limits for individual users or subscribers. Mailbox policies are applied to groups of users and you can have multiple mailbox policies associated with each call plan. Each subscriber can only be associated with a single UM mailbox policy. Policies control include PIN control and settings, dialing rules or access, notifications and fax features.

UM Mailbox Policies

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You can create a new UM Mailbox Policy by using the management console:

  1. Select the Organization Configuration
  2. Select Unified Messaging
  3. Select the UM Mailbox Policies tab
  4. Click New UM Mailbox Policy
  5. Type the name of the UM mailbox policy in the Mailbox policy name section. This is the display for the management console and must be unique
  6. Next to the Select associated dial plan click Browse
  7. In the Select Dial Plan window, click the UM dial plan you want to associate with the policy, and click OK
  8. In the New UM Mailbox Policy wizard, click the New button
  9. On the wizard completion page, click Finish

And you can create a new UM Mailbox Policy by using the management shell:

New-UMMailboxPolicy  -Name MyNewUMPolicy  -UMDialPlan MyDialPlan

Hunt Groups

UM Hunt Groups are used to map the PBX Hunt Group, enabling the UM to identify what line the call originated on and therefore which group of extension to “Hunt” for an open line. A UM Hunt Group must be associated with at least one dial plan on one gateway.

UM Hunt Groups use Pilot Numbers, which maps to the Pilot Numbers programmed into the PBX. Pilot Numbers are presented by the SIP protocol and are used to identify where the call originated and where it should be routed to.

You can create a new UM Hunt Group by using the management console:

  1. Expand the Organization Configuration node
  2. Select Unified Messaging
  3. Select the UM IP Gateway tab
  4. Select an UM IP gateway
  5. Click New Hunt Group
  6. In the Hunt group name field, type the name of the hunt group
  7. In the Dial Plan name field, click Browse
  8. On the Select Dial Plan page, click to select the UM dial plan, and then click OK
  9. In the Pilot identifier field, enter the appropriate pilot identifier and then click New
  10. Click Finish

You can create a new UM Hunt Group by using the management shell:

New-UMHuntGroup  -Name MyHuntGroup  -PilotIdentifier 5554000  -UMDialplan MyDialPlan  -UMIPGateway MyIPGateway

To finish the configuration you must configure dialing rules and associate them with the proper dial plans and mailbox policies. You can also use the GAL grammar generator to generate the initial GAL grammar which is used by the speech engine when negotiating IVR request.

Enabling Users or Subscribers

After the UM is configured, the last logical step is to add users.

You can enable users by using the management console:

  1. Select Recipient Configuration
  2. Select the user mailbox that you want to enable
  3. Select Enable Unified Messaging
  4. On the Enable page, in the Unified Messaging Mailbox Policy box, click Browse
  5. In the Select UM Mailbox Policy window, select the UM mailbox policy, and then click OK
  6. If you have configured an extension number for the user in the Business field on the Address and Phone tab in the user’s properties, the extension will be generated automatically. If you have not configured an extension number for the user, enter the extension number for the user in the Manually entered mailbox extension box
  7. Select Enable page then click Enable
  8. Click Finish

And as before you can enable users by using the management shell:

 Enable-UMMailbox  -Identity [email protected]  -UMMailboxPolicy MyDomainUMPolicy  -extensions 12345

After completing all of the above steps and also configuring settings within each feature, your final step is to test the UM for proper handling of all communications with user and the PBX.

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