One system distributes a request for providing a service using a first communication protocol, from a terminal device to a server selected from among a plurality of servers by a server load balancer in response to the request. A corresponding relation between identification information for identifying a session generated in a distributed server and the server that has generated the session corresponding to the identification information is set in the server load balancer by the service of a second communication protocol as uniqueness assurance information for uniqueness assurance. Thus, when the provision of a service is requested using a second communication protocol by the terminal device, the server load balancer refers to the set uniqueness assurance information and selects the server for providing the service from among the plurality of servers.