Tentacle: user agent of the public information system mediator

In the contemporary society, there is a strong need for the use and development of various Internet accessible services. In developing a faster and simpler model, the mobile access is introduced to the global network. However, development of new services and the run-time support for service providers and users is not satisfactory. A possible approach to the problem is the introduction of the application level middleware as the mediator between the client based access application and server based service logic. The mediator´s deployment spans from different network nodes, including the users´ access devices and services´ hosts in the form of user and service agents. In this paper, we present the user agent of the MidArc public information system mediator. User agent resides on the access device and acts as the users´ personal proxy bridging the gap between client applications and mediator´s core functionalities. The role of the user agent in the two mediator-sited functionalities is considered as well as security policies enforcement and content adaptation mechanism.