Cross Layer Optimization for Protocols in Mobile Adhoc Networks

Doctoral Thesis / Dissertation from the year 2016 in the subject Computer Science - Miscellaneous, grade: 16, , language: English, abstract: In this thesis, we have modified AODV routing protocol by incorporating link prediction algorithm using a proposed link prediction model. This algorithm predicts the link availability time and even before the link breaks; either it repairs the route locally or sends information to the source nodes to enable them to initiate a new route search well in time. This algorithm improves the quality of service of the network. Simulation results show that AODV routing algorithm with link availability model performs better than the existing AODV.

Advances in wireless technology and hand-held computing devices have brought revolution in the area of mobile communication. The increasing mobility of humans across the globe generated demand for infrastructure-less and quickly deployable mobile networks. Such networks are referred to as Mobile Adhoc Networks (MANET). Usually, nodes in a MANET also act as a router while being is free to roam while communicating each others. Adhoc networks are suited for use in situations where infrastructure is unavailable or to deploy one is not cost-effective.

Frequent changes in network topology due to mobility and limited battery power of the mobile devices are the key challenges in the adhoc networks. The depletion of power source may cause early unavailability of nodes and thus links in the network. The mobility of nodes will also causes frequent routes breaks and adversely affects the required performance for the applications.

Availability of a route in future mainly depends on the availability of links between the nodes forming the route. Therefore, it is important to predict the future availability of a link that is currently available. We have proposed an analytical model for link prediction using Newton divided difference method. This link availability algorithm is incorporated in AODV routing algorithm (AODVLP) to evaluate the performance of AODV routing protocol using the metrics viz. delivery rate, average end-to-end delay, average RTS collisions per node and route failure. In the existing AODV protocol, packets are routed until a link in the existing path fails. This results in degradation of quality of service of network in terms of end-to-end delay and delivery ratio.