Applies to: Exchange Server 2010 SP3, Exchange Server 2010 SP2
Topic Last Modified: 2011-04-28
Microsoft Exchange Server 2010 Unified Messaging (UM) can use the Microsoft Office Communications Server 2007 platform to combine voice messaging, instant messaging, enhanced presence, audio/video conferencing, and e-mail into a familiar, integrated communications experience. This communication method has the following benefits:
- Enhanced presence notifications across a variety of
applications that keep users informed of the availability of
- Integration of instant messaging, voice messaging,
conferencing, e-mail, and other communication modes that enables
users to select the most appropriate mode for the task. Users can
also switch from one mode to another as needed.
- Availability of communications alternatives from any location
where an Internet connection is available.
- A smart client (Microsoft Office Communicator 2007) for
telephony, instant messaging, and conferencing.
- Continuity of user experience across multiple devices.
This topic discusses how Exchange 2010 Unified Messaging and Communications Server 2007 can be deployed together to provide voice messaging, instant messaging, enhanced presence, audio/video conferencing, and e-mail into an integrated communication experience for users in your organization.
|To use the features described in this topic, Exchange 2010 must be installed on the computers that have the Unified Messaging server role installed.|
All Communications Server 2007 topologies support Enterprise Voice. Enterprise Voice is an implementation of IP telephony that uses Session Initiation Protocol (SIP) for signaling and Realtime Transport Protocol (RTP) for voice messaging. SIP is an industry standard, application layer signaling protocol for starting, controlling, and ending communication sessions in an IP-based network. SIP is formally described in the International Engineering Task Force (IETF) reference specification RFC 3261.
In Communications Server 2007, SIP is used for instant messaging, conferencing, presence subscriptions, video, and voice messaging. SIP enables Enterprise Voice clients to provide a common user experience across all these communication modes. Enterprise Voice uses RTP for media. Like SIP, RTP is an IETF standard. It defines a packet format for carrying audio and video over IP networks.
When a user places a call from an Enterprise Voice client to a Public Switched Telephone Network (PSTN) destination, the call moves through the Enterprise Voice infrastructure as follows:
- The user places a call from an Enterprise Voice client by
dialing the number or by clicking the name of a contact in
Communicator or Microsoft Office Outlook 2007.
- The Communications Server 2007 server normalizes the telephone
number to E.164 format, and then uses the routing rules based on
location profile and user policy to direct the call to the correct
- The Communications Server 2007 mediation server performs any
necessary media translation and routes the call to the IP
- The IP gateway applies local dialing rules or Private Branch
eXchange (PBX) dialing rules and passes the call to the PSTN, PBX,
or IP PBX.
The following figure illustrates a simple Unified Messaging and Communications Server 2007 topology.
Exchange 2010 Unified Messaging and Communications Server 2007 simple topology
Communications Server 2007 Overview
Communications Server 2007 Enterprise Voice takes advantage of the Unified Messaging infrastructure to provide voice mail, subscriber access, call notification, and auto attendant services. These include the following:
- Phone number normalization Phone number
normalization translates number strings entered in various formats
into a single standard format. Normalization rules specify how to
convert telephone numbers dialed in various formats to standard
- Location profiles A location profile is
a named set of normalization rules that translates telephone
numbers for a location to a single standard (E.164) format for
telephone authorization and call routing. The name of each location
profile must match the fully qualified domain name (FQDN) of its
corresponding Exchange 2010 UM dial plan.
- Phone usage records Phone usage records
provide a quick, easy way to assign call permissions to users. To
enable phone usage records to function correctly, you must assign a
voice policy for the call to be correctly routed to the voice
- Voice policies Enterprise Voice
policies are collections of phone usage records assigned to one or
more users. Most organizations will have multiple voice policies.
Typically, organizations have a global policy that applies to all
users and special policies applied on a per-user basis.
- Call routing The core routing
components for Communications Server 2007 are the Inbound and
Outbound Routing Components, as follows:
- Inbound Routing Component The Inbound
Routing Component handles incoming calls largely according to
preferences specified by users on their Enterprise Voice clients.
Users specify whether unanswered calls are forwarded or logged for
- Outbound Routing Component The Outbound
Routing Component handles calls placed by Enterprise Voice users
either to telephone numbers owned and managed by the enterprise or
to telephone numbers on the PSTN or mobile networks. When an
enterprise user places a call, the Outbound Routing Component looks
up the target number in the Realtime Communication (RTC) database.
If the dialed number matches a SIP Uniform Resource Identifier
(URI) for an enterprise user, the call is routed through all SIP
endpoints for that user.
Important: When you are integrating Exchange Unified Messaging and Office Communications Server, you'll probably find it unnecessary to configure dialing rules or dialing rule groups in Exchange Unified Messaging. Office Communications Server is designed to perform call routing and number translation for users in your organization, and will also do this when the calls are made by Exchange Unified Messaging on behalf of users.
- Inbound Routing Component The Inbound Routing Component handles incoming calls largely according to preferences specified by users on their Enterprise Voice clients. Users specify whether unanswered calls are forwarded or logged for notification.
- Services The setup routing for
Communications Server 2007 installs services that provide support
for voice messaging with Exchange 2010 Unified Messaging, including
- Translation Service The Translation
Service is the application responsible for translating the dialed
number into an E.164 number based on the normalization rules
defined by the administrator.
- Enterprise Services Enterprise Services
performs reverse number lookup on the target telephone number of
each incoming call, matches that number to the SIP URI of the
destination user, and sends the call to that user’s SIP
- User Replicator The User Replicator
extracts user telephone numbers from the Active Directory directory
service and writes them to tables in the RTC database, where they
are available to Enterprise Services and the Address Book
- Address Book Service The Address Book
Service normalizes enterprise user telephone numbers written to the
RTC database to E.164 format to provision user Contacts in
- Translation Service The Translation Service is the application responsible for translating the dialed number into an E.164 number based on the normalization rules defined by the administrator.
To download the reference and Help documentation for Communications Server 2007, see Office Communications Server and Client Documentation Rollup.
Exchange 2010 Unified Messaging
The Unified Messaging server role is one of several Exchange 2010 server roles that you can install and configure on a computer running Exchange 2010. For Enterprise Voice users, Unified Messaging combines voice messaging and e-mail messaging into a single store that can be accessed from a telephone or a computer. Unified Messaging and Communications Server 2007 work together to provide voice mail, subscriber access, and auto attendant services to Enterprise Voice deployments, including the following:
- Voice mail Voice mail includes
answering an incoming call on behalf of a user, playing a personal
greeting, recording a message, and submitting it for delivery to
the user’s Inbox as an e-mail message. Notification of unanswered
calls is sent to the user's Outlook and Outlook Web App Inboxes.
The subject and priority of calls can be displayed in a way that
resembles the way they are displayed for e-mail.
- Subscriber access A subscriber is an
internal business user or network user who is enabled for Exchange
2010 Unified Messaging. Subscriber access is used by users to
access their individual mailboxes to retrieve e-mail, voice
messages, contacts, and calendaring information. Outlook Voice
Access is an Exchange 2010 Unified Messaging feature that lets
subscribers access their Exchange 2010 mailbox. Subscriber access
enables an Enterprise Voice user to access voice mail, calendar,
and contacts from a telephony interface. A subscriber access number
is configured by you on a UM dial plan. For more information about
Outlook Voice Access, see Understanding Unified
Messaging Subscriber Access.
- Auto attendant In telephony or Unified
Messaging environments, an automated attendant or auto attendant
menu system transfers callers to the extension of a user or
department without the intervention of a receptionist or an
operator. In many auto attendant systems, a receptionist or
operator can be reached by pressing or saying zero. The automated
attendant is a feature in most modern PBXs and Unified Messaging
solutions. For more information about auto attendants in Exchange
2010 Unified Messaging, see Understanding Unified
Messaging Auto Attendants.
For more information about Exchange 2010 Unified Messaging, see Unified Messaging.
There are four user scenarios in which Communications Server 2007 and Exchange 2010 Unified Messaging can be used together. These are:
- Call notification User 1 calls User 2.
User 2 doesn't answer the call. User 1 hangs up. User 2 receives an
e-mail message in the Exchange 2010 mailbox that User 1 called.
Call notifications are also sent when an inbound call is forwarded.
User 1 calls User 2. User 2 sets call forwarding to User 3. User 1
calls User 2. The call is forwarded to User 3, and User 2 receives
a call notification that the call was forwarded.
- Leave a voice mail message User 1 calls
User 2. User 2 doesn't answer the call. Because User 2 hasn't
configured call forwarding to another telephone number, the call
from User 1 is diverted to the voice mail for User 2. User 1 is
invited to leave a voice message for User 2. The voice mail
greeting previously recorded by User 2 is played, inviting User 1
to leave a voice message for User 2. User 2 receives a voice mail
message recorded by User 1.
- Subscriber access User 2 dials in to a
subscriber access number and accesses the Exchange 2010 mailbox to
check for voice messages. User 2 can listen to e-mail or voice mail
messages or access the calendar. After listening to the voice
message from User 1, User 2 decides to return the call from User 1.
User 2 accesses the options menu and uses the callback option to
place a call to User 1.
- Auto attendant User 1 doesn't know the
extension number for User 2. User 1 dials in to a telephone number
configured on a UM auto attendant. The welcome greeting and prompts
configured on the auto attendant are played to User 1. User 1 uses
the directory search feature to locate User 2 in the directory and
places a call to the extension number for User 2.
Note: Both subscriber access and those auto attendant services offered by Exchange 2010 Unified Messaging require users to dial specific telephone numbers. These numbers must be routable by Enterprise Voice. This means that each number must be mapped to a SIP address. Communications Server 2007 can route the SIP address to an address configured on the server that has the Exchange 2010 Unified Messaging server role installed.
Exchange 2010 Unified Messaging Active Directory Objects
Exchange Unified Messaging Active Directory objects enable Exchange 2010 Unified Messaging to integrate with the Communications Server 2007 Enterprise Voice infrastructure. To successfully deploy Exchange 2010 Unified Messaging in your organization, you must fully understand the relationship between each of following UM Active Directory objects and their counterparts in Enterprise Voice:
- UM Dial Plan object A UM Dial Plan
object is the basic unit of configuration in Exchange Unified
Messaging. A UM dial plan can be of the following types: Telephone
Extension, SIP URI, or E.164. When Exchange Unified Messaging is
deployed with Communications Server 2007, the dial plan type is
always SIP URI. Users in a UM dial plan reach all other users in
the plan using SIP URIs or SIP addresses. Each SIP address must be
unique within a specific SIP URI dial plan. Each dial plan must
correspond to an Enterprise Voice location profile. The name of
each location profile must match the forest FQDN of the SIP URI
- UM IP Gateway object A UM IP Gateway
object is a logical representation of a physical IP gateway or
SIP-enabled IP PBX. The UM IP Gateway object logically represents
each Communications Server 2007 pool and front-end server as if it
were a physical IP gateway. Each UM IP Gateway object encapsulates
configuration elements related to the corresponding pool or server.
After a UM IP Gateway object is created, it's associated with one
or more UM hunt groups.
- UM Hunt Group object The UM Hunt Group
object associates a UM IP gateway with a UM dial plan. By creating
multiple UM Hunt Group objects, you can associate a single UM IP
gateway with multiple UM dial plans and, therefore, with multiple
Enterprise Voice location profiles.
For more information about the Active Directory objects included in Exchange 2010 Unified Messaging, see Understanding Unified Messaging Components.
The following figure illustrates the relationships between Exchange 2010 Unified Messaging objects and Communications Server 2007 objects.
Unified Messaging and Communications Server 2007 objects and their relationships
Exchange 2010 Unified Messaging combines voice messaging and e-mail messaging into a single messaging infrastructure. Communications Server 2007 Enterprise Voice takes advantage of the Unified Messaging infrastructure to provide voice mail, subscriber access, call notification, auto attendant services and other enhanced features that include voice messaging, instant messaging, enhanced presence, audio/video conferencing, and e-mail into an integrated communication experience for users in your organization. Implementing these services requires integrating Unified Messaging and Communications Server 2007 in a shared Active Directory topology. For more information about the configuration steps required to correctly deploy and integrate Exchange 2010 Unified Messaging and Communications Server 2007, see Deploy Unified Messaging and Communications Server 2007 R2.
To download the reference and Help documentation for Communications Server 2007, see Office Communications Server and Client Documentation Rollup.