To enable the previous scenarios requires deploying Office Communications Server as the Enterprise Voice solution and Exchange Server as the Enterprise Mailbox solution. The additional server role required to enable voice mail when using Exchange Server 2007 SP1 is the Exchange Unified Messaging server role. For details on how to deploy Enterprise Voice, refer to Chapter 11. Information for deploying Exchange Server and UM is beyond the scope of this book.
Exchange UM Server interoperates with several IP gateways as well as Office Communications Server by using SIP over Transmission Control Protocol (TCP) or Mutual Transport Layer Security (MTLS). When interoperating with Office Communications Server, Exchange UM Server uses SIP over MTLS, which offers stronger security. Because most gateways do not integrate with Active Directory, administrators must use the Exchange Server Management Console to create an UM IP gateway object in Active Directory to represent the IP gateway. This object has organization-wide scope. It encapsulates configuration settings related to a single physical IP gateway, including how to connect to the SIP-enabled IP gateway. This enables Exchange UM Server to discover available IP gateways and resolve their addresses by using the Domain Name System (DNS) to route to them. This is a manual process. Every time a new IP gateway is configured, a new UM IP gateway object must be created in Active Directory. When an existing IP gateway is decommissioned, the corresponding UM IP gateway object must be deleted from Active Directory.
In the case of Office Communications Server, the different server roles, with the exception of the Edge Servers, automatically publish themselves in Active Directory during server activation. Unfortunately, Exchange UM Server does not recognize the Active Directory objects that represent the Office Communications Server, which is a trusted server in the Trusted Server list (see Chapter 4, for more details). Therefore, it is necessary to create a corresponding UM IP gateway object in Active Directory for every Standard Edition Server and Enterprise pool front-end server for Exchange UM Server to recognize the Office Communications Server as an IP gateway. This is automated by the tool exchUCutil.ps1, as described in step 4 in the section titled "Configuring Voice Mail" later in this chapter.
Dial rules are used to route incoming calls to the appropriate gateway. In this case, the gateway is an Office Communications Server.
Direct from the Source: Multiple Language Support
Principal Technology Specialist, Unified Communications
If you support international users in your company, perhaps you’re wondering if Exchange UM can support multiple languages without having to deploy additional servers. For example, Litware, Inc Corporation has a primary datacenter located in Los Angeles that houses its Exchange and Office Communications Server servers. They also have an office in Mexico City, and they want to use their existing infrastructure to support those users.
You can manage languages on Exchange UM Servers by using the Exchange Management Console or the Exchange Management Shell administrative interfaces. However, to make a language available in the list on the Settings tab of a UM Dial Plan, you must first install the appropriate UM language pack on the Exchange UM Server by using the following command:
Setup.com /AddUmLanguagePack:<UmLanguagePackName> /s:<LanguagePackFile>
<UmLanguagePackName> is the name of the UM Language pack. For example, es-US for Latin American Spanish. For a complete list of Unified Messaging language packs, see the Exchange Server 2007 SP1 help file or the link, http://technet.microsoft.com/en-us/library/aa995964.aspx.
<LanguagePackFile> refers to the location where the language pack is located.
After installing the appropriate UM language pack, view the list of UM language packs by viewing properties on the UM Settings tab for the Exchange UM Server.
Once a new language pack is installed, a Dial Plan can be configured on the Exchange UM Server so that users retrieving their messages from the Mexico City office will hear their prompts in Latin American Spanish, and the US-English users will continue to hear their prompts in English (see Figure 12-8). Another benefit is that now when the Exchange UM Server is reading the user’s e-mail to them, the messages will be read back in the correct language, in this case, Latin American Spanish for users in the Mexico City office.
Further details about how to create a UM Dial Plan can be found at http://go.microsoft.com/fwlink/?LinkID=133710.
To support Exchange UM’s subscriber access and Auto-Attendant features, Office Communications Server must be able to route those phone numbers to the correct destination. These features require storing routing information that maps the subscriber access or Auto-Attendant phone number to a SIP URI and then into an unconditional forwarding address so that Office Communications Server knows how to route the call to the correct Exchange UM Server. This mapping information is stored in contact objects in Active Directory that are specially marked based on the msRTCSIP-SourceObjectType attribute. The tool, OcsUMutil.exe (described in step 8), automates the process of creating contact objects for each subscriber access and Auto-Attendant associated with a UM Dial Plan that is associated with an IP gateway that corresponds to an Office Communications Server.
The Exchange UM subscriber access feature offers the ability for users to access their mailboxes by using their subscriber access numbers and PINs to dial out from Exchange UM. This dial-out functionality uses Auto-Attendant and Play on Phone features. This functionality requires that Exchange UM Servers be configured with a location profile. When the Exchange UM Server dials out a phone number on behalf of the mailbox user, Office Communications Server must determine which normalization rules to use for normalizing the user-dialed phone number. These normalization rules are defined in a location profile normally assigned to an Office Communications Server. However, the Exchange Active Directory schema does not have any provision to assign a location profile to an Exchange UM Server or preferably a UM Dial Plan, which is more specific to the user calling from Exchange UM. The method for relating a mailbox user to a location profile is matching the name of the location profile and the name of the UM Dial Plan assigned to the user. Therefore, it’s strongly recommended that you not rename the UM Dial Plan and corresponding location profile.
Figure 12-9 illustrates the logical relationship between Office Communications Server and Exchange UM Active Directory schema.
Although these two products are loosely coupled, one can expect Microsoft to better integrate Exchange UM Server and Office Communications Server in future releases.