A scenario including a combination of procedures of multi-factor authentication required for a terminal to receive provision of a service is stored and managed in association with the service, and a probability that the procedure will succeed is stored and managed in association with each of the procedures, a success probability of the service through the scenario, is calculated based on the probability regarding the procedure to evaluate at least one of security and usability based on the success probability, and the service to the terminal, is controlled according to the evaluation result.