| 摘要 |
PURPOSE:To avoid the effect on priority transmission information by a retransmission processing due to a transmission error of other general normal data, by splitting transmission lines into a plurality of data links logically. CONSTITUTION:A data link between nodes A and B is split into two channels P and Q logically and the said P channel is used for priority information transmission and the Q channel is used for normal data transmission. If normal data I0,0(42) transmitted via the Q channel from a station A have errors, a station B transmits a retransmission request REJ,O(45) to the station A via the Q channel. Thus, since the station A transmits information (19) only after the I0,0 of the Q channel again and does not retransmit the priority information of the P channel, unnecessary retransmission processing can be avoided. similarly, if the P channel has any error, the retransmission processing of the normal data of the Q channel can be avoided. |
