Communication Manager supports the industry standard Modem-over-IP (MoIP) to interoperate with secure terminals and third-party SIP gateways. Modem-over-IP uses the Simple Packet Relay Transport (SPRT) protocol to transmit data packets between modem devices.

Modem devices use the V.150.1 protocol to transmit V-series modem signals between modems and telephony devices. The V.150.1 protocol is a standard recommended by International Telecommunication Union (ITU) to use a modem over IP networks that support dialup modem calls. The V.150.1 protocol defines how to transmit modem traffic between modems and telephony devices over an IP network.

With the Modem-over-IP feature, secure terminals establish a secured connection over SIP and H.323 trunks and the Avaya proprietary Inter-gateway Connections (IGCs).

The Modem-over-IP feature operates only with: