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The context information is an intriguing aspect of decision making. The context-awareness can be useful in the ad hoc networks in which nodes are mobile, and the conditions are dynamic. In ad hoc networks, routing protocols are intended to discover the route over multi-hop wireless links under varying conditions. The context-awareness can assist the routing protocols in determining the appropriate path. This paper investigates into choosing the appropriate route by applying the context information and presents the approach to improve the decision making and the quality of the route. We consider nodes, connecting links, and different layers as the context. The paper introduces the scalability and flexibility in the set of parameters that govern the eminence of the node inter-connection that, in turn, influences the overall quality of the route. We propose the context-aware dynamic routing protocol (CADR) and present the approach, algorithm, and analysis. We simulate the protocol by taking the flexible combination of the context attributes and the values, also compares the performance with AODV. The simulation results show that the protocol chooses the appropriate route as per the considered attributes and weight, and provide the enhanced performance

In demand assignment protocol, resources are granted on the basis of demand, governing some rules, policies in resource assignment and after the completion of need, resources are released back to the central pool for further requests. In star topology TDM/TDMA network of VSATs, large number of participating terminals generate signaling packet on common demand request channel. It is desired that these signaling terminals to have higher chances of successful access to the media and at the same time with minimal number of collision over the shared channel. Under these circumstances, performance of media access protocol is really crucial. Aloha is the simplistic technique to access the shared channel but suffers from extremely low throughput. Its immediate successor slotted Aloha improves the throughput by cutting down the vulnerable period to half by agreeing on transmission at slot boundaries. This improvement is also not adequate to provide the better chances of packets getting through when multiple nodes are participating. The large latency network where one hop delay is of the order of 270ms, feedback time and timeouts are also of high order this further worsen the problem. In this paper, we propose self-managed access scheme for demand request that tries to reduce the collision by managing the multiple requests and distributing them over different slots.