| 摘要 |
PROBLEM TO BE SOLVED: To prevent the waste of the assets of a whole system without generating any exceptional processing not by transmitting the information of the temporary disconnection of a data link layer or below and the temporary connection of the re-connection of up to the data link layer to a network layer, and therefore, not by transmitting the information also to the upper layer of the network layer. SOLUTION: In a radio communication system, a ground telephone line between an improved MODEM 11 attached to a user station 2 and a demodulator(DEM) 4 of a center station 1, that is, the line of a data link layer or below repeats disconnection or connection according to the presence or absence of up transmission data. During that time, any layer beyond the network layer of an up line is not disconnected until the end of communication, that is, final line disconnection across the whole layers. In the same way, while at least a line beyond the network layer of the up line is maintained, any down line is not disconnected. Moreover, the factor of the generation of temporary disconnection/temporary connection can be any factor other than the presence or absence of data such as time-out. |
