Bit-oriented protocols (BOP) are organized by non-character structured frames. Within the frames, the userdata and control data are unambiguously defined based on their frame position. Control information is encoded in fields of one or more bits. \nThese protocols have less overhead and are therefore more efficient and reliable than character- or byte-oriented protocols. In addition, they provide duplexoperation. Bit-oriented protocols include Synchronous Data Link Control(SDLC), High Level Data Link Control(HDLC), Link Access Procedure Balanced(LAP B), Advanced Data Communication Control Procedure (ADCCP), among others.