The gateway discovery in hybrid network is considered as a critical and challenging task and with decreasing pause time and greater number of sources it becomes even more complex. Due to the scarcity of network resources in MANET, the efficient discovery of the gateway becomes a key issue in the design and development of future hybrid networks. In this paper the AODV reactive routing protocol is extended to support the communication between the MANET and the Internet. We have described the design and implementation of the various gateway discovery approaches and carried out a systematic simulation based performance evaluation of them using NS2 under different network scenarios. The performance differentials are analyzed on the basis of two QOS parameters - packet delivery fraction and average end-to-end delay.

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Mobile Ad Hoc Network Internet Gateway Discovery Approaches Performance Study Packet Delivery Fraction Average End-to-end Delay