An ITU standard (1972) for synchronous 4,800 bps full-duplex modems for use on four-wire leased lines. It uses DPSK modulation.
link/cite print suggestion box
Browse entries near V.27
V.25
V.25bis
V.26
V.26bis
V.26ter
V.27bis
V.27ter
V.28
V.29
V.32