| 摘要 |
PURPOSE:To prevent re-transmission rate due to an error from increasing one after another by providing a device transmitting consecutively plural identical packets between a packet communication device and a transmission line and regarding it as normal communication when even one of packets transmitted consecutively is received normally even if there is an error in the packet due to error on a transmission line so as not to stop the retransmission of packets. CONSTITUTION:A digit of a sequence number S is divided into two, they are used as upper and lower digits. The upper digit is used as a sequence number SS for transmission/reception of a normal packet and the lower digit is used as a serial number NS for packet serial transmission. For example, in case of four consecutive transmission, the data is transmitted by using 2-bits of 00, 01, 10, 11. In this case, the upper digit has the same number and the data is transmitted with the same packet content. A code error is received in the inter-station transmission, when only D2 is received normally by an input/output device 103 at the reception side, it is regarded as normal reception, it is transmitted to a packet communication device 104 at the reception side, and a packet D is received normally at the packet communication equipment. |
