DTE/DCE interface for asynchronous DTE accessing a pad.
The CCITT recommendation that specifies the user interface between an asynchronous (start/stop) device and a packet assembler/disassembler (PAD).
An International Telecommunication Union (ITU) recommendation. X.28 defines the exchange of commands and responses in an X.25 network between a packet assembler/disassembler (PAD) and the asynchronous terminals attached to it. See ITU and PAD.
CCITT start-stop terminal interface recommendation