A communication processing apparatus that acts as a server for transmitting data to a client includes a data transceiver configured to carry out communications with the client; a rate controller configured to control a bitrate of data transmitted to the client; and a data processor configured to prepare data to transmit in accordance with the bitrate. The rate controller includes a throughput calculator configured to extract an effective data transmission and reception period not including an ineffective data transmission and reception period in a period during which a communication connection is maintained between the server and the client, and to calculate a maximum throughput on the basis of the length of the effective data transmission and reception period and the amount of data transmitted; and a bitrate setter configured to set a bitrate within a range of up to a maximum allowable bitrate corresponding to the maximum throughput calculated by the throughput calculator.