New schemes such as SaaS and PaaS that let users access services over networks are widely used. Moreover, network operators must provide value-added services that enable service providers to create new services promptly and maintain performance as the number of service providers and users increases. To meet these requirements, we proposes a service gateway, which handles user messages (e.g., rewrites the message destination) on the basis of the user location, and a scalable control scheme for the SGW. And we implemented a prototype system to confirm scalability.