Digital telephony is used in the provision of digital telephone services and systems. The upper end of this software can provide a V.110, V.120, V.14, HDLC, or a direct binary framing layer. V.110 is a rate adaptation standard which defines how data terminal equipment (DTE) with asynchronous or synchronous serial interfaces can be supported on an ISDN network through a bit-by-bit alignment between the DTE and the ISDN B channel. V.120 is used to synchronize data streams in North America between a telephony network and asynchronous devices, such as a serial UART.

VOCAL’s embedded software libraries include a complete range of ETSI / ITU / IEEE compliant algorithms, in addition to many other standard and proprietary algorithms. Our software is optimized for execution on ANSI C and leading DSP architectures (TI, ADI, AMD, ARM, MIPS, CEVA, LSI Logic ZSP, etc.). These libraries are modular and can be executed as a single task under a variety of operating systems or standalone with its own microkernel.

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Telephony Signaling

Framing Layers



ITU Recommendation V.110

ITU Recommendation V.120