A general framework for greedy routing in mobile ad-hoc networks

This paper introduces the notion of a reliable and efficient greedy routing provisioning (RGRS) in mobile ad hoc networks.The proposed RGRS constructed of two mechanisms in the context of improving and enhancing greedy routing.These mechanisms are Dynamic Beaconing Update Mechanism (DBUM), and Dynamic and Reactive Reliability Estimation with Selective Metrics (DRESM).The building structure of DRESM is based on the notion of multi-criteria next relay node selection using fuzzy weighted logic multi-objectives.To efficiently track node's status, DRESM is supported with a dynamic and effective updating DBUM scheme.In this work, and to show the performance of the proposed RGRS detailed experiments in simulated environments are executed.The simulation results show that RGRS is quite reliable and efficient and superior to the traditional greedy forwarding strategy (GFS). Moreover, the results reveal that RGRS can be used as a standalone routing protocol without the aid of any recovery mode.RGRS outperforms GFS in terms of the packet delivery ratio. Moreover, RGRS achieves high level of accuracy in terms of nodes’ information and can find routs between communicating nodes whose cost is close to the optimum

GSAR: Greedy Stand-Alone Position-Based Routing protocol to avoid hole problem occurance in Mobile Ad Hoc Networks

The routing process in a Mobile Ad Hoc Network (MANET) poses critical challenges because of its features such as frequent topology changes and resource limitations. Hence, designing a reliable and dynamic routing protocol that satisfies MANET requirements is highly demanded. The Greedy Forwarding Strategy (GFS) has been the most used strategy in position-based routing protocols. The GFS algorithm was designed as a high-performance protocol that adopts hop count in soliciting shortest path. However, the GFS does not consider MANET needs and is therefore insufficient in computing reliable routes. Hence, this study aims to improve the existing GFS by transforming it into a dynamic stand-alone routing protocol that responds swiftly to MANET needs, and provides reliable routes among the communicating nodes. To achieve the aim, two mechanisms were proposed as extensions to the current GFS, namely the Dynamic Beaconing Updates Mechanism (DBUM) and the Dynamic and Reactive Reliability Estimation with Selective Metrics Mechanism (DRESM). The DBUM algorithm is mainly responsible for providing a node with up-to-date status information about its neighbours. The DRESM algorithm is responsible for making forwarding decisions based on multiple routing metrics. Both mechanisms were integrated into the conventional GFS to form Greedy Stand-Alone Routing (GSAR) protocol. Evaluations of GSAR were performed using network simulator Ns2 based upon a defined set of performance metrics, scenarios and topologies. The results demonstrate that GSAR eliminates recovery mode mechanism in GFS and consequently improve overall network performance. Under various mobility conditions, GSAR avoids hole problem by about 87% and 79% over Greedy Perimeter Stateless Routing and Position-based Opportunistic Routing Protocol respectively. Therefore, the GSAR protocol is a reasonable alternative to position-based unicast routing protocol in MANET