METHOD AND DEVICE FOR CONTROLLING LINE

摘要

PROBLEM TO BE SOLVED: To obtain a line control method by which physical layer control and data link layer control are realized even between different protocols by transmitting respective pieces of control information to a user station by means of the frame of the protocol on a downstream line, which is different from that used in the user station and executing line control and data link control. SOLUTION: In a center station transmitting/receiving device 4 and a user station transmitting/receiving device 6, ATM is used for a data link layer protocol and TDM is used for a data link layer protocol in the downstream and PPP is used for the data link layer protocol and FDMA is used for the physical layer protocol in an upstream line as a protocol stack in the case of executing line control and data link control. The response of control information of the physical layer data link layer protocol transmitted in the upstream line is received by the data link layer protocol of the downstream line, which is different from that of the upstream line, and control information are extracted so that line control and data link control are executed.