METHOD FOR CONTROLLING SERVICE QUALITY

PROBLEM TO BE SOLVED: To control service quality based on external situations such as a usual condition, an alarm time situation and an emergency situation in a service system constituted of a plurality of pieces of service.SOLUTION: In the service system to which a plurality of service providing/utilization devices 100 and terminals 110 are connected, a service quality manager 306 determines a situation level from a situation level management table 354 when a first service message is received from a service providing part 302 or a service utilization part 304 (upper layer), calculates a service quality level from first, second service quality definition tables 358, 360, next determines specifications of the service quality from a calculation result of the service quality level and a service quality level definition table 356, and creates a second service message from the specification to be transmitted to a transmitting destination. In addition, when the second service message is received, processing is performed according to a service quality level of the second service message, and the first service message is created to be transmitted to the upper layer.