Communication device and delay detection method

Having: a transmission time stamp generating unit (142,243), which is to be transmitted / received PDU generated or received timestamp; transmission data storage unit (12, 22); receiving a data storage unit (13, 23); frame processing unit (143,244), against which other nodes generates a data update instruction, the transmission data storage unit (12, 22) in the frame period and transmits data acquired from the transmission time stamp generating unit (142,243) including the PDU, if the PDU is received from other nodes, the cycle will be included in the PDU transmission data stored in the received data storage unit (13, 23); and way-delay detecting portion (145,247), which according to the following condition is determined whether the delay PDU from other nodes occurs, i.e., if the received PDU, is whether it is receiving a previous PDU, received in the first delay allowable time to the next PDU, Further, in the a case where the allowable delay time of the next PDU is received from another node to the node of the transmission time of the PDU is in the second allowable delay time.