VOICE-DATA HYBRID TRANSMISSION SYSTEMS IN 64 kbit/sec DIGITAL LINES.

This paper describes the voice-data hybrid transmission facilities, which can be obtained by using 64 kbit/sec digital line. Instead of using separate transmission facilities for voice and data services, or instead of increasing the digital transmission rate, the silent portion of telephonic speech can be used to transmit the data. Two models of the hybrid transmission system are shown. The first model, in which the data arrive randomly in bursts, is useful to describe a kind of interactive process. The second model, in which the data arrive continuously, describes file transfers, facsimile transmissions, etc. The necessary buffers, the blocking probabilities, the data delay, and other factors of both models are calculated.