............... code is used to implement data transparency in the binary synchronous protocol.
............... code is used to implement data transparency in the binary synchronous protocol.
The correct option is A DLE
DLE code is used to implement data transparency in
the binary synchronous protocol.
When it is possible that frame delimiting
characters may appear in the data then it is necessary to provide data
transparency; ie the data must be ignored by the frame synchronisation
system. An example of this would be in a
character oriented protocol when a “binary” file was being transmitted; eg a
compiled program. It could easily contain the ETX code somewhere within the
file. In this case character (or byte) stuffing (or more formally DLE
insertion) is used to achieve data transparency.
This method precedes the “true” STX or ETX
characters with a data link escape (DLE) code. Then the transmitter inserts
(stuffs) a DLE before every DLE it finds in the data. The receiver knows (by
receiving a DLE-STX) that data transparency is in operation. If later in the
frame it finds two DLEs in sequence it will destuff (ie delete one of them) and
pass the second as data. It will therefore recognise the true end of frame (the
only single DLE followed by an ETX).
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 character
encodings for 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.
DLE code is used to implement data transparency in the binary synchronous protocol.
When it is possible that frame delimiting characters may appear in the data then it is necessary to provide data transparency; ie the data must be ignored by the frame synchronisation system. An example of this would be in a character oriented protocol when a “binary” file was being transmitted; eg a compiled program. It could easily contain the ETX code somewhere within the file. In this case character (or byte) stuffing (or more formally DLE insertion) is used to achieve data transparency.
This method precedes the “true” STX or ETX characters with a data link escape (DLE) code. Then the transmitter inserts (stuffs) a DLE before every DLE it finds in the data. The receiver knows (by receiving a DLE-STX) that data transparency is in operation. If later in the frame it finds two DLEs in sequence it will destuff (ie delete one of them) and pass the second as data. It will therefore recognise the true end of frame (the only single DLE followed by an ETX).
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 character encodings for 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.
