Applies to: Exchange Server 2010 SP3, Exchange Server 2010 SP2

Topic Last Modified: 2012-07-24

Microsoft Exchange Server 2010 Unified Messaging (UM) combines voice messaging and e-mail messaging into a single messaging infrastructure. Unified Messaging puts all e-mail and voice messages into one Exchange 2010 mailbox that can be accessed from many different devices. After Unified Messaging servers have been deployed on a network, users can access their messages using Outlook Voice Access, from any telephone, from a mobile phone, or from the computer.

Today, people in organizations frequently manage their voice messages separately from their e-mail messages. Additionally, IT administrators frequently manage the voice mail or telephony networks and the e-mail systems or data networks as separate systems. In these situations, voice mail and e-mail are located in separate inboxes that are hosted on separate servers accessed through the desktop for e-mail and through the telephone for voice mail. Unified Messaging uses the Exchange 2010 store for all messages, including e-mail and voice messages.

Looking for management tasks related to Unified Messaging? See Managing Unified Messaging.

Contents

Overview of Unified Messaging

Benefits of Exchange 2010 Unified Messaging

Configuring a UM Server

Configuring UM Users

Configuring UM Components

UM Call Answering

Overview of Unified Messaging Services

Unified Communications Managed API 2.0

Service Ports

Overview of Unified Messaging

In Microsoft Exchange 2010, the Unified Messaging server role is one of several server roles that you can install and then configure on a computer running Windows Server 2008. Unified Messaging is included with Exchange Server 2007 and Exchange 2010, and it brings with it new telephony concepts that may not be familiar to an Exchange administrator.

Unified Messaging combines voice messaging, fax messaging and e-mail messaging in the Exchange store. Unified Messaging integrates Microsoft Exchange with telephony networks and brings the UM features to the core of Exchange. The following figure shows the relationship between an organization's telephony network components and the UM system.

Overview of Exchange Unified Messaging Topology

In the previous figure, the Unified Messaging solution provides access to telephony systems by using standard Voice over IP (VoIP) protocols. These protocols include Session Initiation Protocol (SIP), Realtime Transport Protocol (RTP), and the T.38 protocol. The IP gateways provide interoperability for legacy Private Branch eXchange (PBX) systems. For details, see Understanding Telephony Concepts and Components.

Note:
Installing and running the Unified Messaging server role in a virtualized environment is supported if you are running Microsoft Exchange Server 2010 Service Pack 1 (SP1) or a later version. The Unified Messaging server role is not supported in a virtualized environment that is running Exchange 2010 RTM.

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Benefits of Exchange 2010 Unified Messaging

The Exchange 2010 Unified Messaging solution offers benefits for the end user and also for the IT administrator.

User Benefits

When you deploy Exchange 2010 Unified Messaging, users can access voice mail, e-mail, and calendar information that's located in their Exchange 2010 mailbox from an e-mail client, for example, Outlook or Microsoft Office Outlook Web App, from a mobile phone with Microsoft Exchange ActiveSync set up, such as a Windows Mobile phone, or from a telephone. Additionally, users will be able to use the following features:

  • Access to Exchange information   UM-enabled users can access a full set of voice mail features from Internet-capable mobile phones, Microsoft Office Outlook 2007, Outlook 2010, and Outlook Web App. These features include many voice mail configuration options and the ability to play a voice message from either the Reading Pane, using an integrated Windows Media Player, or the message list, using computer speakers.

  • Play on Phone   The Play on Phone feature lets UM-enabled users play voice messages over a telephone. If the user works in an office cubicle, is using a public computer or a computer that isn't enabled for multimedia, or is listening to a voice message that's confidential, they might not want to or be able to listen to a voice message through computer speakers. They can play the voice message using any telephone, including a home, office, or mobile telephone.

  • Voice mail form   The Outlook 2007, Outlook Web App, and Outlook 2010 voice mail form resembles the default e-mail form. It gives users an interface for performing actions such as playing, stopping, or pausing voice messages, playing voice messages on a telephone, and adding and editing notes.

    The voice mail form includes the embedded Windows Media Player and an Audio notes field. The embedded Windows Media Player and notes field are displayed in either the Reading Pane when users preview a voice message or in a separate window when they open the voice message. If users aren't enabled for Unified Messaging, or if Outlook 2007 hasn't been installed on the client computer, they view voice messages as e-mail attachments, and the voice mail form isn't available.

  • User configuration   A user who's enabled for Unified Messaging can configure several voice mail options for Unified Messaging using Outlook Web App. For example, the user can configure telephone access numbers and the voice mail Play on Phone number, and can then reset a voice mail access PIN.

  • Call answering   Call answering includes answering incoming calls on behalf of users, playing their personal greetings, recording messages, and submitting them for delivery to their Inbox as an e-mail message.

  • Call Answering Rules   Call Answering Rules is a new feature in Exchange 2010. Using this feature, end users can dictate how their incoming call answering calls should be handled. The way call answering rules are applied to incoming calls is similar to the way Inbox rules are applied to incoming e-mail messages. By default, no call answering rules are configured. If an incoming call is answered by a Unified Messaging (UM) server, the caller is prompted to leave a voice message for the called party. Using call answering rules, a caller can:

    • Leave a voice message for the UM-enabled user.

    • Transfer to an alternate contact of the UM-enabled user.

    • Transfer to the alternate contact's voice mail.

    • Transfer to other phone numbers that the UM-enabled user has configured.

    • Use the Find-Me feature or locate the UM-enabled user via a supervised transfer.

  • Voice Mail Preview   In Exchange 2010, the Unified Messaging server role uses ASR on newly created voice mail messages. When users receive voice messages, the messages contain both a recording and text that's been created from the voice recording. Users see the voice message text displayed in an e-mail message from within Outlook Web App, Outlook 2007, or Outlook 2010.

  • Message Waiting Indicator   Message Waiting Indicator is a feature found in most legacy voice mail systems and can refer to any mechanism that indicates the existence of a new message. In Exchange 2007, this functionality was provided by a third-party application, which indicated receipt of a new voice message by lighting the lamp on the desk phone. This feature has been added to Exchange 2010, and third-party software isn't needed. Enabling or disabling Message Waiting Indicator is done on the user's mailbox or on a UM mailbox policy.

  • Missed call and voice mail notifications using SMS   When users are members of a hosted or consumer dial plan, and they configure their voice mail settings with their mobile phone number and configure call forwarding, they can receive notifications about missed calls and new voice messages on their cell phones in a text message via the Short Messaging Service (SMS). However, to receive these types of notifications, the users must first configure text messaging and also enable Notifications on their account.

  • Protected Voice Mail   Protected Voice Mail is Unified Messaging functionality that enables users to send private mail. This mail is protected by Active Directory Rights Management Services (AD RMS), and users are restricted from forwarding, copying, or extracting the voice file from e-mail. Protected Voice Mail increases the confidentiality of Unified Messaging, and lets users rely on Unified Messaging if they want to limit the audience for voice messages. This functionality is similar to the way private e-mail messages were handled in Exchange 2007. In Exchange 2010, it also applies to voice mail messages.

  • Outlook Voice Access   There are two Unified Messaging user interfaces available to UM-enabled users: the telephone user interface (TUI) and the voice user interface (VUI). These two interfaces together are called Outlook Voice Access. Subscribers can use Outlook Voice Access when they access the Unified Messaging system from an external or internal telephone. UM-enabled users who dial in to the Unified Messaging system can access their mailbox using Outlook Voice Access. Using a telephone, a UM-enabled user can:

    • Access voice mail

    • Listen to, forward, or reply to e-mail messages

    • Listen to calendar information

    • Access or dial contacts who are stored in the global address list or a group in their Contacts

    • Accept or cancel meeting requests

    • Set a voice mail message to let callers know the called party is away

    • Set user security preferences and personal options

  • Group addressing using Outlook Voice Access   In Exchange 2007, users could use either the telephone user interface (TUI) or voice user interface (VUI) in Outlook Voice Access to send e-mail and voice messages when they logged on to their mailbox. However, users could only send a single e-mail message to a single user in their personal Contacts, to multiple recipients from the directory by adding each recipient individually, or by adding the name of a distribution list from the global address list. In Exchange 2010, when a user signs in to their mailbox using Outlook Voice Access, they can also send e-mail and voice messages to users in a group stored in their personal Contacts.

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Benefits for Administrators

Currently, most users and IT departments manage their voice mail separately from their e-mail. Voice mail and e-mail exist as separate inboxes hosted on separate servers accessed through the desktop for e-mail and through the telephone for voice mail. Unified Messaging offers an integrated store for all messages and access to content through the computer and the telephone.

Exchange administrators can manage Unified Messaging using the same interface they use to manage the rest of Exchange, using the Exchange Management Console and the Exchange Management Shell. They can:

  • Manage voice mail and e-mail from a single platform

  • Manage Unified Messaging using scriptable commands

  • Build highly available and reliable Unified Messaging infrastructures

Exchange 2010 Unified Messaging offers administrators:

  • A complete unified messaging system   Exchange 2010 Unified Messaging offers a true unified messaging solution using a single store, transport, and directory infrastructure. The store is provided by the Exchange 2010 Mailbox server role. The transport is provided by the Exchange 2010 Hub Transport server role. All e-mail and voice mail messages can be managed from a single management point, using a single administration interface and tool set. This greatly reduces the overall cost of administration by consolidating infrastructure and training.

  • An Exchange 2010 deployment and administration model   Using the Exchange 2010 Unified Messaging solution, you can take advantage of the Exchange 2010 server design. You aren't required to purchase a new server to run the Unified Messaging server role. More important, you can reuse your Exchange knowledge, including training and troubleshooting methodology, and apply it to managing your voice mail infrastructure.

  • An Exchange 2010 security model   The Microsoft Exchange Unified Messaging service runs as an Exchange server account. This means that you don't have to create or manage a super user account for Exchange 2010 Unified Messaging.

  • Consolidation of voice mail systems   Currently, most voice messaging systems require that all the voice messaging system components be installed in every physical office location in an organization. In this kind of arrangement, the voice messaging systems in branch offices are located outside the central office and must be administered onsite. This frequently results in increased administration costs and complexity. Exchange 2010 Unified Messaging lets you manage your voice mail system from a central location. To create a centralized management system for Unified Messaging, you can place all Unified Messaging servers in a datacenter or location, and then deploy IP gateways in each of your branch offices that replace the voice messaging system for each branch office. Deploying a centralized voice messaging system in this manner can result in a significant savings in hardware and administrative costs.

  • Built-in Unified Messaging administrative roles   A set of roles for managing Unified Messaging and voice mail features has been defined within Exchange 2010. Administrative roles that included UM were available in Microsoft Exchange Server 2007. The following UM-specific administrative roles have been added for Exchange 2010:

    • UM Mailboxes

    • UM Prompts

    • Unified Messaging

  • Incoming fax support   Exchange 2007 provided built-in support for fax message creation through the Unified Messaging server role. A user with a UM-enabled mailbox could receive fax messages from calls placed to his or her phone number. There's no support in Exchange 2007 UM for inbound fax routing, or for outgoing fax.

    In Exchange 2010, direct support for fax has been removed from the Unified Messaging server role. Customers who require a fax solution that works with Exchange 2010 will have to deploy a fax partner solution. Fax partner solutions are available from several fax partners. The fax partner solutions are designed to be tightly integrated with Exchange 2010 and enable UM-enabled users to receive incoming fax messages.

    Note:
    If you’re using the RTM version of Exchange 2010 Unified Messaging, you may have to enable inband fax tone detection for fax receiving to work correctly with some IP PBXs. You do this by changing the EnableInbandFaxDetection setting to True in the msexchangeum.config file. The msexchangeum.config file is located in the \Program Files\Microsoft\Exchange\V14\bin folder on an Exchange 2010 Unified Messaging server. If you don't configure this setting, Unified Messaging servers must rely on IP gateways to perform inband fax tone detection.

    Changing the EnableInbandFaxDetection setting to True in the msexchangeum.config file isn't required in Exchange 2010 Service Pack 1 (SP1). Enabling fax tone detection isn’t necessary on a Unified Messaging server with Exchange 2010 SP1 installed because the Unified Communications Managed API v. 2.0 (UCMA) enables the Unified Messaging server to listen to both inband and out-of-band fax events.
  • Support for multiple languages   For Exchange 2010, all available language packs contain the Text-to-Speech (TTS) engine and the prerecorded prompts for a specified language and ASR support. However, only some language packs contain support for Voice Mail Preview. The US English (en-US) language pack is included on the Exchange 2010 DVD and additional UM language packs can be downloaded from the Microsoft Download Center.

  • Auto attendant   An auto attendant is a set of voice prompts that gives external and internal users access to the Exchange 2010 Unified Messaging system. The telephone keypad or speech inputs can be used to move through the auto attendant menu, place a call to a user, or locate a UM-enabled user and then place a call to them. An auto attendant gives the administrator the ability to:

    • Create a customized menu for external users.

    • Define informational greetings, business hours greetings, and non-business hours greetings.

    • Define holiday schedules.

    • Describe how to search the organization's directory.

    • Describe how to connect to a user's extension so external callers can call users by specifying their extension.

    • Describe how to search the organization's directory so external callers can search the organization's directory and call a specific user.

    • Enable external users to call the operator.

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Configuring a UM Server

During an installation of the Unified Messaging server role, a UM computer object is created in the Computers container in Active Directory. The UM computer object created in Active Directory is a representation of a physical server on which the Unified Messaging server role is installed. The UM Active Directory computer objects connect your organization's telephony infrastructure and the UM Active Directory networking environment.

Note:
For a new UM computer object to be created during installation, the UM server must be a member of a domain before the Unified Messaging server role is installed.

After the computer object is created, you can perform the procedures for deploying Unified Messaging on your network.

Server Operation

By default, the operational status of the UM server is set to Enabled after the Unified Messaging server role is installed. This lets the UM server process incoming and outgoing voice calls and route the messages to their intended recipients in your Exchange organization. A UM server won't process incoming calls unless the operational status is set to Enabled.

The operational status of the UM server can be controlled using the Enable and Disable commands in the EMC and the Shell. There are three status modes for UM servers:

  • Enabled   Process all incoming calls.

  • Disable immediately   Don't accept any new calls and drop all existing calls.

  • Disable after completing calls   Don't accept any new calls but process all existing calls.

When the UM server starts, it locates all UM IP gateways associated with the server and associated with the existing UM dial plan. To detect and determine any configuration changes on either UM dial plans or UM IP gateways, the UM server will either register a change notification or re-check the configuration every 10 minutes.

If the UM IP gateway list changes, the UM server will react accordingly and either start to use or stop using the IP gateways that are associated with the UM server's dial plan. After a UM server is working as an associated member of a UM dial plan and is communicating with an IP gateway or a PBX, you can run a set of diagnostic operations to verify that it's connected and operating correctly.

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Configuring UM Users

When you mailbox-enable a user, you're given the option to create a mailbox or to connect to an existing mailbox. After a user is connected to an existing mailbox or a mailbox is created for them, you must enable the mailbox so the user can use Unified Messaging. After the user is enabled for Unified Messaging, all e-mail and voice messages will be delivered to the user's mailbox. UM users can access their e-mail, voice messages, and calendaring information by using Outlook 2007, Outlook 2010, Outlook Web App, a mobile phone that's enabled for Exchange ActiveSync, or a regular or mobile phone.

Note:
To enable multiple UM users, use the Enable-UMMailbox cmdlet in the Shell.

User UM Properties

After a user is enabled for Unified Messaging, you can manage, modify, and configure the UM properties for the user.

There are two locations in which UM properties are stored for a user: the Mailbox object and the user's Active Directory object. When you enable a user for Unified Messaging, you set the UM property on the user's Mailbox object. After the Mailbox property is set to Enabled for Unified Messaging, the user can use the UM features found in Exchange 2010.

After a user is enabled for Unified Messaging, the user's UM properties, such as the user's extension number, spoken name, and other properties for the user, are stored in the user's properties in Active Directory and on the user's mailbox.

You can manage UM properties for an Active Directory user on the mailbox of the UM user by using the Shell or the EMC.

The Relationship of the UM User to a UM Mailbox Policy

When you enable a user for Unified Messaging, the user must be associated with or linked to an existing UM mailbox policy and you must provide the extension number for the user. You can associate a user with a UM mailbox policy by using the Enable-UMMailbox cmdlet or by selecting the UM mailbox policy when you create the user's Exchange mailbox.

A UM mailbox policy contains settings such as the dialing restrictions and PIN policies for a user. When a UM mailbox policy is created, the UM mailbox policy must be associated with only one UM dial plan. The UM dial plan is then automatically associated with at least one UM server. Any UM server that's associated with the UM dial plan can provide UM services for a UM-enabled user who uses the UM dial plan. Associating these Active Directory objects in this manner delivers the UM services by using Active Directory. After the user is enabled for Unified Messaging, the settings from a UM mailbox policy are applied to the UM-enabled user.

Configuring UM Components

Exchange 2010 Unified Messaging provides voice messaging services using objects that take advantage of your current Active Directory environment. UM Active Directory objects are created to support Unified Messaging. Active Directory acts as the container for all these UM objects and their configuration settings.

UM Active Directory objects make it possible for UM to interact with the telephony infrastructure. This physical infrastructure and the relationship between its components are mirrored in Active Directory. For details, see Understanding Unified Messaging Components.

Some UM Active Directory objects are created to represent each telephony hardware device, and other UM Active Directory objects are created to represent a telephony dial plan for an organization or to support a specific feature of Unified Messaging. For details, see Understanding Telephony Concepts and Components.

The following example and figure show the relationships between the UM objects found in Active Directory.

UM Logical Relationships

In the previous figure, the UM servers represented as Server01, Server02, and Server03 are located in the datacenter for a company. These servers are also represented as UM Server objects in Active Directory. Additionally, there are two UM dial plans, the Boston UM dial plan and the New York UM dial plan. There is a single PBX for each office. However, there are two IP gateways per PBX at each branch office to provide fault tolerance. Finally, Server01 and Server02 are members of the Boston UM dial plan, and Server01, Server02, and Server03 are all members of the New York UM dial plan.

When a call comes in to the PBX in the New York branch office and the call is forwarded to a UM server, any one of the three UM servers can answer the call and deliver the message to the user's mailbox because all the UM servers belong to the same dial plan. When a call is received in Boston for a user and the call is forwarded to a UM server, either Server01 or Server02 can answer calls for the users in the Boston dial plan.

There are several key Active Directory objects you need to create and manage. These objects are outlined in the following sections.

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UM Dial Plans

In a traditional telephony dial plan, users' extensions are configured on an IP PBX, PBX, or multiple PBXs and share a common numbering plan. This makes it possible for users to dial one another's telephone extensions without dialing a full telephone number.

A UM dial plan mirrors a telephony dial plan. UM dial plans are required to successfully deploy Unified Messaging on your network.

A UM dial plan is an Active Directory object that represents sets or groupings of IP PBXs or PBXs that share common user extension numbers. UM dial plans in Unified Messaging require that user telephone extension numbers be unique.

In some telephony networks, multiple PBXs and multiple dial plans exist. In these telephony networks, there can be two users who have identical telephone extensions if the two users who have the same extension number are placed in two separate UM dial plans. Putting the two users in separate dial plans makes their extension numbers unique for Unified Messaging purposes.

The following figure shows how UM dial plans can be used in an organization that has a single forest and multiple physical sites.

Unified Messaging Dial Plans

How Dial Plans Work

After you install the Unified Messaging server role on an Exchange 2010 computer, you must associate the UM server with at least one UM dial plan before it will answer calls. You can also associate a single UM server with multiple UM dial plans.

After the UM server is associated with a UM dial plan, you must create a UM IP gateway and associate it with the UM dial plan that was created.

Important:
Each time you create a UM dial plan by using the EMC, a UM mailbox policy will also be created. The UM mailbox policy will be named <DialPlanName> Default Policy.

Creating and associating the UM dial plan and UM server objects in Active Directory enables the UM server to receive calls from the IP gateway or IP PBX and then process incoming calls for users who are associated with the UM dial plan. When a call comes in to the IP gateway or IP PBX, the IP gateway or IP PBX forwards the call to a UM server and the UM server tries to match the extension number of the user to the associated UM dial plan. The dial plan is identified from the pilot numbers that are sent by the IP gateway or IP PBX when an incoming call is received. The pilot numbers that are configured on a PBX or IP PBX may also be configured on a UM dial plan as a subscriber access number. For details, see Understanding Unified Messaging Dial Plans.

When you integrate a telephony network with Unified Messaging, there must be at least a single IP gateway or SIP-enabled IP PBX that connects your telephony network with your IP-based network. Each IP gateway or IP PBX in your organization is represented by a UM IP gateway object in Active Directory.

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UM Mailbox Policies

UM mailbox policies are required when you enable users for Unified Messaging. They're useful for applying and standardizing UM configuration settings for UM-enabled users. You create UM mailbox policies to apply a common set of policies or security settings to a collection of UM-enabled mailboxes. You use Unified Messaging mailbox policies to set UM settings for UM-enabled users, such as the following:

  • PIN policies

  • Dialing restrictions

  • Other general UM mailbox policy properties

For example, you can create a UM mailbox policy to increase the level of PIN security by reducing the maximum number of logon failures before a user will be locked out for a specific group of UM-enabled users, such as executives.

UM mailbox policies are created in the Configuration container in Active Directory by using the Shell or the EMC. By default, a single UM mailbox policy is created every time you create a UM dial plan. The new UM mailbox policy is associated with the UM dial plan and part of the dial plan name is included in the display name of the UM mailbox policy. However, you can create additional UM mailbox policies based on the needs of your organization. Although a single UM mailbox policy is required to enable users for Unified Messaging, you can create additional UM mailbox policies and apply a common set of mailbox policy settings for other groups of users.

The mailbox of each UM-enabled user must be linked to a single UM mailbox policy when the mailbox is enabled for Unified Messaging. After you create a UM mailbox policy, you link one or more UM-enabled mailboxes to the UM mailbox policy. This lets you control PIN security settings such as the minimum number of digits in a PIN or the maximum number of logon attempts for the UM-enabled users who are associated with the UM mailbox policy. If you prefer, you can also control message text settings or dialing restrictions for the same or a different group of UM-enabled mailboxes.

Multiple UM-enabled users can be linked to a single UM mailbox policy. However, a single user can be associated with only one UM mailbox policy. After you create a new UM mailbox policy and link it to a UM dial plan, the UM mailbox policy settings that are defined are applied to the UM-enabled users. The settings that are defined on a UM dial plan and a UM mailbox policy will be applied to all users who are associated with the UM mailbox policy.

The following figure shows how UM mailbox policies can be created to control dialing restrictions and PIN security settings for three different groups.

UM Policies

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UM IP Gateways

A UM IP gateway is an Active Directory object that represents a physical IP gateway hardware device, an IP PBX, or another SIP server that can interoperate with Unified Messaging. Before the physical IP gateway, IP PBX, or SIP server can be used to process UM calls, it must be represented in Active Directory by an UM IP gateway object.

Although there are many types and manufacturers of PBXs, IP gateways, and IP PBXs, there are basically two types of IP gateway component configurations:

  • IP PBX   A single device

  • PBX (legacy) and an IP gateway   Two separate components

To support Unified Messaging, one or both types of IP device configurations are used when connecting a telephony network with a data network.

The UM IP gateway can be associated with one or more Active Directory UM hunt groups. The combination of the UM IP gateway object and a UM hunt group object establishes a link between an IP gateway hardware device and a UM dial plan.

Enabling and Disabling UM IP Gateways

By default, UM IP gateways are left in an enabled state after they're created. However, the UM IP gateway can be enabled or disabled. If you disable a UM IP gateway, it can be in one of two disabled modes. The first disabled mode forces all associated UM servers to drop existing calls. The second disabled mode forces the UM server associated with the UM IP gateway to stop handling any new calls presented by the IP gateway.

Note:
Before an IP gateway can be used to process calls, a UM IP gateway must be associated with at least one UM dial plan. Also, at least one UM server must be associated with at least one UM dial plan. If a UM IP gateway is deleted, the UM servers associated with the UM IP gateway will no longer be able to accept or process new call requests from the IP gateway or IP PBX.

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UM Hunt Groups

In a telephony network, a hunt group is defined as a set of extension numbers that are grouped as a single unit. When an incoming call is received, the PBX or IP PBX uses the hunt group to "hunt" for an available or open line, extension, or channel that can be used to receive the call.

Hunt groups are used to efficiently distribute calls into or out of a specific unit. For example, a PBX or IP PBX might be configured to have 10 extension numbers for a sales department. The 10 sales extension numbers would be configured as one hunt group.

Multiple algorithms or methods have been created for use by a PBX or IP PBX to define how the open line, extension, or channel will be located. These include the following:

  • Round robin

  • Most idle

  • Start with lowest number

Creating and defining a hunt group in a PBX or IP PBX reduces the possibility that a caller who places an incoming call will receive a busy signal when the call is received.

Understanding UM Hunt Groups

UM hunt groups are used to define the PBX or IP PBX hunt group from which incoming calls will be received and are very important to the operation of the UM system. The UM hunt group represents an existing PBX or IP PBX hunt group. UM hunt groups act as a connection or link between the UM IP gateway and the UM dial plan. A single UM hunt group is associated with at least one UM IP gateway and one UM dial plan.

The pilot number defined for a hunt group in the physical PBX or IP PBX must also be defined for the UM hunt group. A pilot number is a telephone number that points to a hunt group and is the phone number for calls that are routed to Unified Messaging servers. The pilot number is used to match the information presented with incoming calls using the SIP header on the message. The pilot number enables the UM server to interpret the call together with the correct dial plan so that the voice message can be routed correctly. It's very important to configure UM hunt groups correctly, because incoming calls that don't correctly match the pilot number defined on the UM hunt group won't be answered and incoming call routing will fail.

When you create a UM hunt group, you're enabling all UM servers specified within the UM dial plan to communicate with an IP gateway. If you delete the UM hunt group, the associated IP gateway will no longer service calls by using the specified pilot number. If the IP gateway is left without remaining UM hunt groups, the IP gateway won't be able to handle incoming calls.

UM Auto Attendants

Unified Messaging enables you to create one or more UM auto attendants, depending on the needs of your organization. UM auto attendants can be used to create a voice menu system for an organization that lets external and internal callers move through the UM auto attendant menu system to locate and place or transfer calls to company users or departments in an organization.

When anonymous or unauthenticated users call an external business telephone number, or when internal callers call a defined extension number, they're presented with a series of voice prompts that help them place a call to a user or locate a user in the organization and then place a call to that user. The UM auto attendant is a series of voice prompts or .wav files callers hear instead of a human operator when they call an organization that has Unified Messaging. The UM auto attendant lets callers move through the menu system, place calls, or locate users by using DTMF or voice inputs. However, for automatic speech recognition (ASR) or voice inputs to be used, you must enable ASR on the UM auto attendant.

Important:
In some companies (especially in East Asia), office telephones may not have letters on the keys of the telephone. This makes the spell-the-name feature that uses the DTMF interface almost impossible without a working knowledge of the key mappings. By default, Unified Messaging uses the E.161 key mapping. For example, 2=ABC, 3=DEF, 4=GHI, 5=JKL, 6=MNO, 7=PQRS, 8=TUV, and 9=WXYZ. When a combination of letters and numbers is inputted, for example "Mike1092", the numeric digits are mapped to themselves. For an e-mail alias of "Mike1092" to be entered correctly, the user must press the numbers 64531092. Also, there won't be a telephone key equivalent for characters other than A-Z and 0-9. Therefore, these characters shouldn't be entered. For example, the e-mail alias "mike.wilson" would be entered as 6453945766. Even though there are 11 characters to be input, only 10 digits are entered by the user because the period (.) doesn't have a digit equivalent.

The UM auto attendant:

  • Provides corporate or informational greetings.

  • Provides custom corporate menus so that you can link a menu option to another auto attendant to have more than one level.

  • Provides a directory search function that enables a caller to search an organization's directory for a name.

  • Enables a caller to connect to the telephone of, or leave a message for, members of the organization.

In Active Directory, each UM auto attendant created is represented as an object. There is no limit to the number of UM auto attendants you can create in Active Directory. Each auto attendant can support an unlimited number of extensions. A UM auto attendant is associated with one, and only one, UM dial plan. However, UM auto attendants can reference or link to other UM auto attendants.

An incoming call that is received from an external telephone number or an internal telephone extension is processed by a UM server and then sent to a UM auto attendant that has been created. The UM auto attendant is configured by the system administrator to use prerecorded voice (.wav) files that are then played over the telephone to the caller and that enable the caller to move through the UM menu system. When you configure a UM auto attendant, you can customize all the .wav files that are used to meet the needs of your organization. For more information about custom prompts in Unified Messaging, see Understanding Unified Messaging Audio Prompts.

For more information about message flow with UM auto attendants, see Unified Messaging Auto Attendant Call Processing.

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Auto Attendant with Multiple Languages

There are situations in which you may have to provide callers with auto attendants that have different languages. The language setting that's available on a UM auto attendant lets you configure the default prompt language on the auto attendant. When you're using the default system prompts for the auto attendant, the default prompt language is the language that the caller will hear when the auto attendant answers the incoming call. This language setting will affect only the default system prompts that are provided when the Unified Messaging server role is installed. This setting won't affect custom prompts that have been configured on an auto attendant. The language selected as the default for the auto attendant is based on the version of Exchange 2010 installed.

When you install the U.S.-English version of Exchange 2010, there will be only one language available to configure on UM auto attendants: U.S. English. However, if you install a localized version of Exchange 2010, for example, Japanese, you'll be able to configure the auto attendant you create to use Japanese or U.S. English as the default language. Additional UM language packs can be installed on a UM server to let you use other default language options on an auto attendant.

Caution:
You can't install UM language packs using the .msi file for the language.

For example, if you have a business that's based in the United States but requires a menu system that gives callers the options of moving through the system in U.S. English, Spanish, and French, you have to first install the UM language packs that you need. In this case, if you've installed the U.S.-English version of Exchange 2010, you'd install the UM language packs for Spanish and French. However, because a UM auto attendant can have only one language configured at a time, you'd create four auto attendants: a main auto attendant configured to use U.S. English and then one auto attendant for each language: U.S. English, Spanish, and French. You'd then configure the main auto attendant to have the appropriate key mappings to access the other auto attendants you've created for each language. In this example, the main auto attendant would answer the incoming call and the caller would hear, "Welcome to Contoso, Ltd. For English, press or say 1. For Spanish, press or say 2. For French, press or say 3."

Auto Attendant Examples

The following examples demonstrate how you can use UM auto attendants together with Unified Messaging:

  • Example 1   At a company called Contoso, Ltd., external customers can use three external telephone numbers: 425-555-1111 (Corporate Offices), 425-555-2222 (Product Support), and 425-555-3333 (Sales). The Human Resources, Administration, and Accounting departments have internal telephone extensions and must be accessed from the Corporate Offices UM auto attendant.

    To create a UM auto attendant structure that supports this scenario, create and configure three UM auto attendants that have the appropriate external telephone numbers. Create three other UM auto attendants for each department in the Corporate Offices. Then you configure each UM auto attendant based on your requirements, such as the greeting type or other navigational information.

    The following figure is a graphical representation of how UM auto attendants can be used in Example 1.

    UM Auto Attendants

  • Example 2   At a company called Contoso, Ltd., external customers call one main number for the business, 425-555-1000. When an external caller calls the main number, the UM auto attendant answers and prompts the caller by saying, "Welcome to Contoso, Ltd. Please press or say 'One' to be transferred to corporate administration. Please press or say 'Two' to be transferred to product support. Please press or say 'Three' to be transferred to corporate information. Please press or say 'Zero' to be transferred to the operator." To create a UM auto attendant structure that supports this scenario, you create a UM auto attendant that has customized extensions that route the call to the appropriate extension number.

    The following figure is a graphical representation of how UM auto attendants can be used in Example 2.

    Unified Messaging Auto Attendants

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UM Call Answering

This section describes how Unified Messaging handles message flow in different incoming call scenarios.

Unified Messaging handles the following types of incoming calls:

  • Voice

  • Outlook Voice Access

  • Play on Phone

  • Auto attendant

Unified Messaging depends on Active Directory to route incoming calls. For call answering to function correctly, each UM-enabled recipient must have a telephone extension number listed in Active Directory. The extension number for the recipient is listed in Active Directory and is mapped to the extension number that is configured on the user's UM-enabled Exchange mailbox. When a UM server answers a call, an Active Directory lookup is performed to locate the appropriate UM-enabled recipient, and then the message is routed to the recipient's mailbox.

Message Flow

Message flow in Unified Messaging is the process by which a message that's received by a UM server is routed in an Exchange 2010 organization.

Note:
In earlier versions of Microsoft Exchange, routing groups were used to route messages between bridgehead servers. In Exchange 2007 and Exchange 2010, bridgehead servers are known as Hub Transport servers. There are no routing groups in Exchange 2007 or Exchange 2010.

For example, in an incoming call scenario that includes incoming voice messages, a UM server uses the SMTP transport to submit the voice message to the Exchange 2010 server that has the Hub Transport server role installed. In a routing scenario that includes multiple Hub Transport servers, the incoming voice mail message is first submitted to the closest Hub Transport server and is then routed to the appropriate Mailbox server that contains the UM-enabled mailbox.

Note:
To make sure all incoming messages are transmitted and delivered to UM-enabled recipients, the UM servers use a spooling or retry algorithm. The UM servers try to connect to a Hub Transport server every 30 seconds to submit all messages that are stored on the UM server.

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Voice Call Processing

Voice calls that come in to an Exchange 2010 organization can be placed by callers who are inside or outside the organization. When a caller places a call to a UM-enabled user's telephone extension and the user isn't available to answer the call, the PBX forwards or routes the incoming call to an IP gateway and then to the UM server. In a UM system that uses an IP PBX, the IP PBX forwards the incoming message to the UM server. The IP gateway or the IP PBX translates or converts the incoming audio stream into RTP for incoming voice messages. The stream of IP data is then passed to the UM server. After the UM server receives the call, the UM server processes the message and determines how to route the message.

The following figure shows how incoming voice messages flow in an Exchange 2010 organization.

Voice and Fax Message Flow

In this example, a call arrives at the PBX and is then forwarded to the UM pilot number. The pilot number is mapped to the hunt group that goes to the IP gateway. The IP gateway presents the call to the UM server. The UM server then receives SIP invitation header information such as who the call is for, who the caller is, and why the call was redirected. The UM server then looks up the number that was called and identifies which user was called and which dial plan the user belongs to. From there, the UM server looks in Active Directory to see whether the user is enabled for Unified Messaging. If the user is enabled for Unified Messaging, the caller receives a greeting for the user. Users' greetings are securely stored in their mailbox. This lets them manage their greetings. After callers reach the user's voice mail greeting, they can leave a voice message that will be sent to the user's mailbox. The UM server then records the message, locates a Hub Transport server, and submits the voice message to the Mailbox server that contains the UM-enabled user's mailbox.

UM Auto Attendant Message Processing

When external or anonymous callers place a call by using an external business telephone number, or internal anonymous callers place a call to an internal extension number, they're presented with voice prompts to help them move through the UM menu system. The UM auto attendant is a set of voice prompts or .wav files that are played to callers instead of a human operator or receptionist when they call in to an organization that has Unified Messaging. Unified Messaging lets you create one or more auto attendants, depending on the needs of your organization.

Auto Attendant Message Flow

When a call is received by a UM server, the UM server performs a Lightweight Directory Access Protocol (LDAP) query to an Active Directory domain controller to determine how to handle the incoming call.

The following figure shows the message flow when UM auto attendants are used in an Exchange 2010 organization.

Auto Attendant Message Flow

After you've created and enabled the auto attendant for your organization and associated it with a UM dial plan, the auto attendant can start to process calls. When a call for an auto attendant is received, it's first processed by the IP gateway and mapped to the appropriate hunt group. The call is then sent to the UM server. The UM server looks up the auto attendant object in Active Directory and then provides the correct auto attendant to handle the call.

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UM Outlook Voice Access Call Processing

With Unified Messaging, UM-enabled users can access their e-mail, voice mail, contacts, and calendaring information using a standard analog, digital, or mobile telephone. Using Outlook Voice Access, a UM-enabled user can:

  • Listen to new and saved e-mail and voice mail messages.

  • Forward, reply to, save, and delete e-mail and voice mail messages.

  • Interact with their calendar.

  • Locate a person in the global address list or their personal Contacts.

  • Send a voice message to a person.

  • Change their PIN, spoken name, or greetings.

Outlook Voice Access Message Flow

Incoming calls that are received by a UM server from an Outlook Voice Access user are only routed to a Mailbox server to enable users to access their mailbox. However, if a message is submitted by using Outlook Voice Access, for example, a change in the schedule of a meeting, the message is first submitted to a Hub Transport server within the same Active Directory site as the UM server before it's routed to the recipient's mailbox.

The following figure shows how incoming calls and messages placed by subscribers or UM-enabled users flow in an Exchange 2010 organization.

Outlook by Phone Message Flow

When a user calls in to Outlook Voice Access, the PBX receives the call for the UM number and the IP gateway presents the call to the UM server. The UM server then looks up the user account information in Active Directory and collects information about the user. This information includes dial plan information. If users place the call from their own extension, they're prompted for their PIN. The UM server contacts the Mailbox server and authenticates the user. From there, the UM server and the Mailbox server communicate information back to the user, as requested.

Overview of Unified Messaging Services and Components

When you install the Unified Messaging (UM) server role on a computer running Exchange 2010, several UM-specific components and services are installed. The Unified Messaging services and components installed by Setup enable a Unified Messaging server to answer and process incoming voice calls and enable users to interact with the Unified Messaging system by using Outlook Voice Access or by hearing a UM auto attendant when they call in to the Unified Messaging system.

Beginning with Exchange 2010 SP1, the UM server relies on Unified Communications Managed API v. 2.0 (UCMA) for its underlying SIP signaling and media, and speech processing. This dependency requires that the UCMA platform and prerequisites be installed on the UM server before Exchange 2010 UM SP1 installation or upgrade.

The following figure illustrates the relationships between Unified Messaging components.

Unified Messaging Architecture

Unified Messaging Services

The Microsoft Exchange Unified Messaging service is one of the two services that provide Unified Messaging services for your network. The Microsoft Exchange Unified Messaging service performs the following functions:

  • Retrieves the dial plan configuration from Active Directory

  • Loads the configuration information for monitoring UM worker processes from the Msexchangeum.config file

  • Initializes the UM Worker Process Manager and the startup of a UM worker process

  • Registers SIP endpoints

The Microsoft Exchange Unified Messaging service first accepts all incoming connections, and then reroutes those requests to a UM worker process that handles the incoming request. In addition, the Microsoft Exchange Unified Messaging service monitors any UM worker process that's created and ensures that the UM worker process is functioning correctly. If a UM worker process becomes unresponsive, the Microsoft Exchange Unified Messaging service stops the UM worker process and then creates a new UM worker process to replace it.

Note:
By default, each UM worker process will be recycled every seven days or 604,800 seconds. The setting can be found in the V14\bin\Msexchangeum.config file.

The Microsoft Exchange Unified Messaging service works with the Microsoft Exchange Speech Engine service to implement all the telephony features offered by Unified Messaging. The Microsoft Exchange Unified Messaging service handles call control and interacts with the Unified Communications Managed API 2.0 to handle the incoming media streams that are negotiated in the SIP signaling information between the Microsoft Exchange Unified Messaging service and a SIP-enabled telephony device such as an IP gateway or IP PBX. The following events happen when an incoming call is initiated by the Microsoft Exchange Unified Messaging service:

  1. A call session is initiated by the Microsoft Exchange Unified Messaging service.

  2. The Microsoft Exchange Unified Messaging service redirects the call to a UM worker process.

  3. The UM worker process requests that a media session be established with Unified Communications Managed API 2.0, and then the UM worker process relays the media information back to the caller.

  4. Unified Communications Managed API 2.0 provides a UDP port for the RTP stream.

  5. The UM worker process uses the SIP signaling information to inform Unified Communications Managed API to end the call session when the RTP media stream is no longer needed.

UM Worker Process

A UM worker process is a process that's created during the startup of the Microsoft Exchange Unified Messaging service. UM worker processes interact with all incoming and outgoing requests received by the Microsoft Exchange Unified Messaging service.

The UM Worker Process Manager is also a component of the Microsoft Exchange Unified Messaging service. The UM Worker Process Manager handles the creation and monitoring of all the UM worker processes that are created. The UM Worker Process Manager creates new instances of a UM worker process based on the configuration settings located in the Msexchangeum.config file and also monitors the health of these processes. As a new incoming call arrives, the UM Worker Process Manager determines the appropriate instance of a UM worker process to redirect the call to. The UM worker process then interacts with the Unified Communications Managed API 2.0 components to correctly process incoming and outgoing requests. The UM worker process is responsible for the following startup tasks:

  • Allocation of the runtime management objects

  • Loading of the Unified Messaging configuration from Msexchangeum.config

  • Registration of the process with Unified Communications Managed API 2.0

  • Initialization of Simple Mail Transfer Protocol (SMTP) message submission

Unified Communications Managed API 2.0

Starting with Exchange 2010 SP1, the Unified Messaging server role relies on the Microsoft Unified Communications Managed API v. 2.0 (UCMA). UCMA simplifies the architecture of Unified Messaging and doesn't include any dependencies of other Windows-based or Exchange-based services. UCMA can be broken down into the following areas:

  • SIP Signaling   SIP signaling in UCMA v. 2.0 is very similar to SIP signaling in UCMA v. 1.0.

  • RTP Media   UCMA provides access to RTP media streams.

  • Collaboration   provides presence and conferencing support.

UCMA v. 2.0 is a managed-code platform that enables developers to build applications that provide access to and control over Enhanced Presence information, instant messaging, telephone and video calls, voice messaging, and audio/video conferencing. It enables both text-based and voice-based (speech technology-enabled) conversations and collaboration. UCMA v. 2.0 is intended to support the development of server side, middle-tier applications targeting Microsoft Office Communicator 2007 R2, Office Communications Server 2007 R2, or Microsoft Lync Server 2010 (the next generation of Office Communications Server) and Exchange 2010. It contains a SIP stack, a media stack, powerful speech engines for both Automatic Speech Recognition (ASR), as well as speech synthesis that's generated by Text-to-Speech (TTS).

UCMA v. 2.0 can be used to add communications capabilities to your business software and processes. It can also be used to create outbound applications such as alerts, notifications, or surveys, as well as inbound speech technology-enabled interactive voice response applications and automated agents. UCMA v.2.0 provides access to the presence information available in Communications Server 2007 R2 and can be used to build role agents that use Microsoft Enhanced Presence information to streamline communications between people.

UCMA v.2 makes more advanced developer scenarios possible, for applications such as automated call distributors, which perform skill-based routing; for conferencing services, such as conference access control; for custom client gateways that can interface with, for example, other communications networks, other Interactive Voice Response platforms, and with speech servers that are using the Microsoft ASR and TTS engines.

The UCMA platform replaces the Microsoft Exchange Speech Engine service and the Speech Engine service worker process (SESWorker.exe) and controls the following:

  • The DTMF (touchtone) interface.

  • ASR, which is used with the voice user interface (VUI) in Outlook Voice Access.

  • The TTS engine that reads e-mail, voice mail, and calendar items and plays the menu prompts for callers.

UCMA v. 2.0 also supports the following features in Unified Messaging:

  • ASR input recognition.

  • DTMF (touchtone) input recognition.

  • The TTS conversion process.

  • Recording e-mail and voice mail messages.

  • Playing e-mail and voice mail messages for users.

As a result of the integration of UCMA and Unified Messaging, you receive the following benefits when you integrate UM and Microsoft Lync Server 2010:

  • Unified Messaging reports Quality of Experience (QoE) data to Lync Server 2010 Quality of Experience Monitoring or QMS servers. This is available in both on-premises and cross-premises integrated environments.

  • UM doesn't drop the first incoming call if the first call to the UM server is being made from an Enterprise Voice user who's connected the Internet.

In earlier versions of Office Communications Server, the A/V Edge resources that were associated with the Office Communications Server pool didn't communicate with a specific UM server for a specific call. This led to less-than-optimal media quality in some scenarios. With Exchange 2010 SP1, you can set, on a per UM-server basis, the Office Communications Server pool and associated A/V Edge server resources that should be used for all calls to and from that specific UM server.

Prerequisites for UCMA

The Unified Messaging server role in Exchange 2010 SP1 relies on the following, and requires that they be installed prior to installing SP1:

Windows Remote Management (WinRM) 2.0 and Windows PowerShell V2 (Windows6.0-KB968930.msu) - Windows Management Framework Core package (Windows PowerShell 2.0 and WinRM 2.0)

For more information about UCMA, see UCMA 2.0 Core Architecture.

For more information about the grammar files used in Unified Messaging, see Understanding Automatic Speech Recognition Directory Lookups.

Service Ports

The Microsoft Exchange Unified Messaging service and the UM worker process use multiple Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) service ports to communicate with IP gateways. The Microsoft Exchange Unified Messaging service and the UM worker process use Session Initiation Protocol (SIP) over TCP. By default, the Microsoft Exchange Unified Messaging service listens on both TCP port 5060 in Unsecured mode and TCP port 5061 when mutual Transport Layer Security (mutual TLS) is used. Each UM worker process that's created listens on port 5065 and 5067 (unsecured) and 5066 and 5068 (secured). But when an IP gateway or IP PBX sends Realtime Transport Protocol (RTP) traffic to the Speech Engine service worker process, the IP gateway or IP PBX will use a valid UDP port that ranges from 1024 through 65535.

A TCP control port is also used on a Unified Messaging server. When a UM worker process is created, the Microsoft Exchange Unified Messaging service passes the appropriate configuration options to the UM worker process. The configuration options sent include the parameters for the TCP control port number that's used for communication between the Microsoft Exchange Unified Messaging service and the UM worker process. The TCP control port that's chosen will be between TCP ports 16,000 to 17,000.

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