State Information Accuracy in Mobile Ad-Hoc Networks Using OLSR

To support QoS routing, accurate state information (such as energy level and queue length) should be available and manageable. But due to bandwidth constraints, communication costs, high loss rate and the dynamic topology of MANETs, getting and keeping up-to-date state information is a very complex task, if at all feasible. In this work, we use Optimized Link State Routing (OLSR) as the underlying routing protocol. This research reports the quantification of state information accuracy under different traffic rates. State information accuracy is defined as how far off is the believed QoS-related state information from its actual value. The results show that state information is inaccurate, especially under high traffic rates. Tuning the OLSR protocol parameters has no noticeable impact on inaccuracy levels. Based on our inaccuracy level analysis, we proposed three additional techniques for the energy level metric and two techniques for the queue length metric as an attempt to reduce inaccuracies. We compare the different techniques against each other and against the basic OLSR. For energy level, two of our proposed techniques have shown significant improvements in inaccuracy levels. On the other hand, no improvement was observed for queue length related techniques.