PBX and IP gateways vs. IP PBXs
Unified Messaging server roles are deployed as part of the Exchange 2007 Server deployment. The Unified Messaging role need only be added with the default configurations during the server installation.
In short, a three-step process is used to integrate UM with a VoIP solution: Install the UM Server role, install and configure the IP gateway with the legacy PBX or install an IP PBX, and then configure the UM Server role to use the IP gateway or IP PBX.
Legacy PBX and IP gateways
Legacy PBXs vary greatly. Your choice of an IP gateway should be based on its support for the legacy PBX. The critical features that need to be supported by the IP gateway are:
- Line provisioning type - T1 PRI CAS trunk, T1 PRI, ISDN BRI, individual voice lines.
- Signaling integration - SMDI, Q.SIG, or digital set emulation (DSE). Q.SIG and DSE have built-in signaling integration. T1 CAS requires SMDI for signaling.
- Line call plan - Settings on the PBX that define the supported call scope. This can be as broad as worldwide and as limited as internal calls only.
- Hunt group/pilot number - If existing hunt groups and pilot numbers are in place from an existing solution, consider whether you want to reuse voicemail numbers or create new ones.
It is important to review the, "PBX Configuration Notes – Tested by Microsoft or Gateway Vendor Partners," at http://www.microsoft.com/technet/prodtechnol/exchange/pbx-partners.mspx to locate the configuration notes document for the PBX and IP gateway that you will be using.
These documents are created by the vendor specifically to show how to configure their devices to work with your PBX. Reviewing the capabilities of these documents prior to purchasing an IP gateway is recommended so you can make an informed decision. The supported IP gateways are listed in Table 3.
|Vendor||IP Gateway||Supported Protocols|
|AudioCodes||MediaPack 114/8 FXO||Analog with In-Band DTMF
Analog with SMDI
|AudioCodes||Mediant 1000||T1/E1 Q.SIG|
|AudioCodes||Mediant 2000||T1/E1 CAS
|Dialogic||PIMG80PBXDNI||Digital Set Emulation|
|Dialogic||PIMG80LS||Analog with In-Band DTMF
Analog with SMDI
|Dialogic||TIMG300DTI, TIMG600DTI||T1 CAS
The IP PBXs that are supported by Exchange 2007 Unified Messaging Server are few and far between. However, the list is expected to grow as adoption of Unified Messaging increases. The key to their integration is support for SIP over TCP. Table 4 lists the currently supported IP PBXs.
|PBX Manufacturer||PBX Model/Type||Minimum Software Version|
|Avaya||Avaya Communication Manager||V2.0|
|Interactive Intelligence||Customer Interaction Center||2.4|
|Mitel||3300 CXi, CX/MXe||7.1 UR2|
|Nortel Networks||CS 1000 (a.k.a. CS1K)||5.0|
Microsoft Exchange Server 2007 Unified Messaging for administrators
Home: Introduction to Unified Messaging on Exchange 2007
Part 1: An intro to voice systems for Exchange administrators
Part 2: Unified Messaging features in Exchange Server 2007
Part 3: Defining Exchange Unified Messaging architecture
Part 4: Deploying Unified Messaging servers on Exchange Server 2007
Part 5: Comparing VoIP PBX solutions for Unified Messaging
Part 6: Integrating Unified Messaging servers with a VoIP solution
Part 7: Creating a Unified Messaging Dial Plan
Part 8: Configuring a Unified Messaging IP gateway
Part 9: Mailbox policy configuration for Unified Messaging
Part 10: Creating and assigning a Unified Messaging hunt group
Part 11: Dialing rules and restrictions for Unified Messaging users
Part 12: Assigning Unified Messaging dialing rules to a mailbox policy
Part 13: Executing Unified Messaging grammar generation
Part 14: Enabling Unified Messaging mailboxes and users
|This chapter excerpt from Microsoft Exchange Server 2007: The Complete Reference, by Richard Luckett, William Lefkovics and Bharat Suneja, is printed with permission from McGraw-Hill Osborne Media, Copyright 2008.|
This was first published in January 2009