An ITU-T modem protocol which allowed half-duplex (unidirectional) data transmission at 1200 bits per second with a 75 bps back channel and fall back to 600/75 bps. This was the main standard used for British Telecom's Prestel service.
Last updated: 2004-07-26
V.17 ♦ V.21 ♦ V.22 ♦ V.22bis ♦ V.23 ♦ V.24 ♦ V.25 ♦ V.25 bis ♦ V.27 ter ♦ V.28
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