To provide a technique for processing communication data at a high speed.

A log output control device 145 includes a database in which data included in a log output from a communication control device functioning as an SIP server which processes a message of a session establishment protocol and a method of outputting the log containing the data are stored, while being made to correspond to one another; a plurality of log output ports 143 for outputting the log to other devices, a retrieval circuit which acquires the log from the communication control device and retrieves the data included in the log from the database; and an output unit which acquires a method of outputting the log from the database, in accordance with the retrieval result of the retrieval circuit, determines a log output port 143 for outputting the log by the method, and outputs the log from the log output port 143.