It's challenging to create guidelines for deploying telephony networks. They can be very different from one another because they can include IP gateways, IP PBXs, and PBXs with different configuration settings, firmware, and requirements. This diversity makes planning and deploying Unified Messaging somewhat challenging. However, several resources are available to help you successfully deploy Unified Messaging:

• Unified Messaging specialists   UM specialists are systems integrators who have received technical training about Exchange 2010 Unified Messaging conducted by the Exchange engineering team. To help ensure a smooth transition to Exchange 2010 Unified Messaging from legacy voice mail systems, Microsoft recommends that all customers engage a UM specialist. For contact information, visit Microsoft Exchange Server 2007 Unified Messaging (UM) Specialists.
  
  
• PBX configuration notes   PBX configuration notes contain configuration settings and other information that's very useful when you're configuring IP gateways, IP PBXs, and PBXs to communicate with the Unified Messaging servers that are on your network. For more information, see PBX Configuration Notes Tested by Microsoft or IP Gateway Vendor Partners for Exchange 2010 Unified Messaging.
  
  

Before you engage a Unified Messaging specialist, you should be able to answer key questions that they'll ask. Having the answers to the following questions will help make the conversation between you and the UM specialist productive:

• How many existing telephone or voice mail users, or both, are in your organization?
  
  
• How many users do you intend to provide with Exchange 2010 Unified Messaging?
  
  
• Which PBX or PBXs do you intend to use for integration with Exchange 2010 Unified Messaging?
  
  
• How many PBXs does your organization have? Specify the vendors, types (circuit- or IP-based), models, and firmware versions.
  
  
• Are the PBXs networked, and are they centralized or located in multiple locations?
  
  
• What voice mail system or systems does your organization currently use? Specify the vendors, types, models, and firmware versions.
  
  
• How are the voice mail systems integrated into your PBXs (Analog, T1/E1, PRI, Digital set emulation, VoIP, other)?
  
  
• Are you currently using voice networking?
  
  
• What type of fax system or systems does your organization use, and does the fax system or systems support inbound fax routing to Exchange?
  
  
• Does your organization use automated attendants?
  
  
• Do you need support for phone-only users, that is, users who won't have e-mail access?
  
  

Integrating Exchange 2010 Unified Messaging with PBXs requires you to use one or more IP gateways to translate the circuit-switched protocols that are used by TDM-based PBXs to IP-based, packet-switched protocols that are used by Exchange 2010 Unified Messaging. IP gateway vendors with several models of IP gateways have been tested and are supported for Exchange 2010 Unified Messaging.

Interoperability testing of Exchange 2010 Unified Messaging with IP gateways is now integrated with the Microsoft Unified Communications Open Interoperability Program. For more information, see Microsoft Unified Communications Open Interoperability Program.

The Microsoft Unified Communications Open Interoperability Program qualification program for IP gateways and IP PBXs ensures that customers have a seamless setup and support experience when they're using qualified telephony gateways and IP-PBXs with Microsoft Unified Communications software. Only products that meet rigorous and extensive testing requirements and conform to the specifications and test plans receive qualification.

Interoperability was verified for the following IP gateway vendors in the following years:

• AudioCodes
  
  
• Dialogic
  
  
• The following table shows the IP gateway vendor, the IP gateway model, and the protocols that are supported by each model.
  
  

Supported IP gateways for Unified Messaging

The following table shows the PBXs that are supported using AudioCodes IP gateways including MediaPack-114 FXO, MediaPack-118 FXO, and Mediant 2000.

PBXs Supported with an AudioCodes IP gateway

Each Dialogic IP gateway model supports different PBXs. The following tables show the PBX manufacturer and model and which Dialogic IP gateway can be used. Each IP gateway uses different signaling methods, densities, and protocols.

PBXs Supported Using a DMG1000 Series Media Gateway

PBXs Supported Using a DMG 2000 Series Media Gateway

PBXs Supported Using a DMG4008BRI Series Media Gateway

IP PBXs are also supported by Exchange 2010 Unified Messaging. The following table shows the IP PBXs that are supported using a direct SIP connection to Exchange 2010 Unified Messaging.

IP PBXs supported using a direct SIP connection

IP PBXs using SIP media gateways are also supported by Exchange 2010 Unified Messaging. The following table shows the IP PBXs that are supported using IP to IP capabilities of SIP media gateways to connect to Exchange 2010 Unified Messaging.

IP PBXs supported using a SIP Media Gateway

Exchange 2010, Microsoft Office Communications Server 2007 R2, and Microsoft Lync Server 2010 can be deployed together to provide voice messaging, Instant Messaging (IM), enhanced user presence, audio-video conferencing, and an integrated e-mail and messaging experience for users in your organization. For more information, see:

• Office Communications Server 2007 Document: Enterprise Voice Planning and Deployment Guide
  
  
• Understanding Unified Messaging and Communications Server 2007 R2
  
  
• Deploy Unified Messaging and Communications Server 2007 R2
  
  
• Lync Server 2010
  
  

To find out more about the Microsoft Unified Communications Open Interoperability Program for enterprise telephony infrastructure, including finding qualified SIP PSTN gateways and IP PBXs and the process for telephony infrastructure vendors to join and participate in the program, see Microsoft Unified Communications Open Interoperability Program.