Individualization of network services will be a key factor attracting users because customer satisfaction with identified services such as location-specific and time-specific news could increased by collecting and analyzing user information. Balancing the trade-off between privacy and individualization, however, will require the use of technical mechanisms we call identified-service support systems (ISSS). Here we describe the basic concept of an ISSS and describe its technical requirements. We propose an ISSS architecture combining user-information analysis for individualization, access control for privacy protection, shuffling data management for preventing the leakage of personal information, and digital signatures for authenticating the integrity of partially disclosed documents. We also describe the protocols, GUIs, and data management implementations of a prototype ISSS developed for personalized broadcasting services. An ISSS could protect user privacy against inside attacks as well as third-party attacks and could support various kinds of identified services.