Security in ad hoc networks is a major issue when it comes to real deployment of services over this sort of networks. A large amount of research effort was directed toward routing in ad hoc networks, however securing the connectivity and the packet transmission is a brake in relying on an ad hoc network as any other infrastructure based network. In this paper, we propose a secured architecture over ad hoc network based on the AAA concept (Authentication, Authorisation, Accounting), and a new ad hoc nodes design for any kind of ad hoc nodes to securely support part or full AAA services