Transmission management system, management method, and carrier means

A transmission management system (40), in response to receiving a registration request for registering a candidate counterpart terminal in a candidate list of a first transmission terminal (10), determines whether a target of the registration request is a second transmission terminal or a group. The management system (40) transmits, to the second transmission terminal an approval request for requesting whether to approve registering the second transmission terminal as a candidate counterpart terminal in the candidate list of the first transmission terminal, when the target of the registration request is determined to be the second transmission terminal. The registrant (84) registers the second transmission terminal as a candidate counterpart terminal in the candidate list of the first transmission terminal based on a response indicating approval for registration from the second transmission terminal. The management system (40) transmits, to an administrator terminal (20) operated by an administrator of the group, an approval request for requesting whether to approve registering all transmission terminals (10) in the group as candidate counterpart terminals in the candidate list of the first transmission terminal, when the target of the registration request is determined to be the group. The registrant (84) registers all the transmission terminals (10) in the group as candidate counterpart terminals in the candidate list of the first transmission terminal based on a response indicating approval for registration from the administrator terminal (20).