A contract-based approach for secure service discovery systems

Future distributed computing systems will be ubiquitous and provide accesses to a wide range of services at any time, every where, and from a variety of devices. The monitoring and controlling accesses to services are one of the fundamental challenges that must be faced in the context of ubiquitous and pervasive environments. To address services accesses issues, it is necessary to guaranty the user access to utilize the allowed and available services. More precisely, an access control must be granted to services in order to regulate their usage. In this paper, a contract-based approach for monitoring and controlling accesses to services in ubiquitous environments is presented. In this approach, client agents and server agents are bounded by contracts: the server agent expects that the client agent will not attempt to access other services than those it required, and the client agent expects that the server agent will provide the required service.