COMMUNICATION NETWORK SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a communication network system in which an optimal communication system can be selected in accordance with the state of a communication path or of a communicating party. SOLUTION: A communication terminal 10a includes a transmission system selection table wherein a plurality of transmission patterns are made to correspond to transmission destination addresses and recorded. A transmission system and communication state information are made to correspond to transmission patterns. A test communication performing part 26 refers to the transmission system selection table and creates a test telegraphic message according to the transmission system included in each transmission pattern. After transmitting the created test telegraphic message, the text communication performing part 26 updates the communication state information on the basis of an ACK response transmitted from another communication terminal. When creating a message, a communication control part 22 selects a transmission pattern from the transmission system selection table on the basis of priority conditions. The communication control part 22 creates the message on the basis of the transmission system included in the selected transmission pattern and transmits the telegraphic message via a communication part 24. COPYRIGHT: (C)2004,JPO&NCIPI