Binary Synchronous Communications

Binary Synchronous Communications

Binary Synchronous Communication (BSC or Bisync) is an IBM character-oriented,half-duplex link protocol, announced in 1967 after the introduction of System/360. It replaced the synchronous transmit-receive (STR) protocol used with second generation computers. The intent was that common link management rules could be used with three different alphabets for encoding messages. Six-bit Transcode looked backwards to older systems; USASCII with 128 characters and EBCDIC with 256 characters looked forward. Transcode disappeared very quickly but the EBCDIC and USASCII dialects of Bisync continued in use.

At one time Bisync was the most widely used communications protocol and is still in limited use in 2012.