TRANSMISSION OF COUNTERMEASURE DATA THROUGH A MANAGEMENT DATA SESSION BETWEEN TWO TERMINALS UPON FAILURE OF CONTENT DATA SESSION BETWEEN SAID TERMINALS
A transmission terminal (10) communicates contents data with a counterpart transmission terminal (10) through a first session, and transmits management data to a management system (50) through a second session. When a predetermined event that may prevent or interrupt communication with a user at the counterpart terminal (10) is detected, the transmission terminal (10) obtains countermeasure data, and transmits the countermeasure data to the management system (50) through the second session.