Complete Communications Engineering

V.91 Modem SoftwareV.91 modem software is fully compliant with the ITU V.91 Recommendation and optimized for most architectures. ITU-T V.91 specifies the operation of a duplex digital modem for use on a 4-wire circuit switched connection and on leased point-to-point 4-wire digital circuits at data signalling rates of up to 64 kbit/s. Contact us to discuss your V.91 modem application requirements.

download brochure for V.91 Modem Software

VOCAL’s V.91 modem software is optimized for performance on leading DSP architectures and processors from TI, Intel, ADI, AMD and other vendors. Our modem software may be licensed standalone, as a library or complete design. Custom designs are also available to meet specific modem application requirements.

Virtual Modem over IP

VOCAL’s SIP Software modem (MoIP or V.MoIP) solution provides developers a range of solutions to connect legacy dial up modems to modem infrastructure. Unlike other virtual modem designs, the SIP software modem can communicate with a physical modem at the far end using a VoIP service over an IP network.

V.91 Software Features

V.91 Modem

The V.91 digital modem is specified in terms of coding, start-up sequences, operating procedures and DTE-DCE interface functionalities.  ITU V.91 includes an optional control channel and support for transparent mode on unrestricted 64 kbit/s channels. The network interface and the signalling rate that is used to connect the V.91 modem locally to a 4-wire connection are considered to be country specific matters and are hence not specified.

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supported platforms for V.91 Modem Software

VOCAL’s optimized software is available for the following platforms. Please contact us for specific V.91 supported platforms.