(Bisynch) An
IBM link
protocol, developed in
the 1960 and popular in the 1970s and 1980s.
Binary Synchronous Transmission has been largely replaced in
IBM environments with
SDLC. Bisync was developed for
batch communications between a System 360 computer and the
IBM 2780 and 3780
Remote Job Entry (RJE) terminals. It
supports RJE and on-line terminals in the
CICS/
VSE
environment. It operates with
EBCDIC or
ASCII character sets. It requires that every message be acknowledged (
ACK)
or negatively acknowledged (NACK) so it has high
transmission overhead. It is typically character oriented and
half-duplex, although some of the bisync protocol flavours
or dialects support binary transmission and
full-duplex
operation.