Supported IP/VoIP Hardware

Exchange Server 2010 unified messaging relies on the capability of the IP/VoIP gateway to translate time-division multiplexing (TDM) or telephony circuit-switched based protocols, such as Integrated Services Digital Network (ISDN) or QSIG, from a PBX to protocols based on voice over IP (VoIP) or IP, such as Session Initiation Protocol (SIP), Real-Time Transport Protocol (RTP), or T.38 for real-time facsimile transport.

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

• IP/VoIP Gateway—A legacy PBX and an IP/VoIP gateway provisioned as two separate devices. The Unified Messaging server communicates with the IP/VoIP gateway.

• IP/PBX—A modern IP-based or hybrid PBX such as a Cisco CallManager. The Unified Messaging server communicates directly with the PBX.

Table 20.2 lists the currently supported IP/VoIP gateways.

Table 20.2 Supported IP/VoIP Gateways for Exchange 2010 UM

To support Exchange Server 2010 unified messaging, one or both types of IP/VoIP device configurations are used when connecting a telephony network infrastructure to a data network infrastructure.

All these solutions must communicate with the unified messenger through SIP over TCP (TLS encrypted) and SRTP.