摘要
Many real-time applications, handling a large amount of data, require a real-time database system, RTDBS, which provides adequate mechanisms to guarantee time constraints during transaction execution and data access. Deploying real-time applications using data services in mobile ad hoc networks (MANETs) implies several constraints. The key challenging is providing the application time constrained services with node limited resources. Indeed, the mobile nodes lifetime has to face unpredictable requests leading to an overload, a battery exhaustion or a service unavailability. In this work, we propose a quality of service, QoS, architecture to handle real-time transaction execution in MANETs. Appropriate parameters are needed to capture the unstable system behavior and the limited autonomy. The proposed architecture is based on a cross-layer approach and integrates the network layer QoS parameters with the ones specified at the application layer, useful in the service selection step. The proposed solution includes (i) an energy and delay aware routing protocol and (ii) a cross-layer service selection protocol, ensuring both timeliness and energy efficiency by avoiding low-power and busy service provider nodes. Simulation results prove that the protocols offered within the cross-layer architecture, decrease the deadline miss ratio of packets, increase the service availability and extend the network lifetime.