CABLE MODEM AND DATA TRANSMISSION CONTROL PROGRAM

PROBLEM TO BE SOLVED: To provide a cable modem capable of reducing congestion of an incoming channel of a CATV network even in the case of using a PC terminal or the like belonging to an individual user and performing transmission control of data so as to gain throughput optimum to the user. SOLUTION: This cable modem 6 is used in an information transmission system for transmitting information data owned by a server connected to the Internet to a PC terminal 7 via the Internet and an outgoing channel of the CATV network 4, and connected between the PC terminal 7 and the CATV network 4. When the information data is downloaded on the basis of a download request from the PC terminal 7, ACK (acknowledge character) data is transmitted by at least two types of transmission time intervals, and the ACK data is transmitted by a transmission time interval with the highest throughput of the information data downloaded by the respective transmission time intervals. COPYRIGHT: (C)2005,JPO&NCIPI