Fig. 5

CLT versus overhead. Figure describes an experiment during which, we consider a service life time ranging from 0 to 40% of the total simulation time. The Performance achieved is captured in terms of overhead messages for all SD protocols under study. An increase in the CLT increases the time a SDY remains in the node’s cache. An entry in the cache is only useful when the same request is repeated in the same node before the elapse of CLT. In the case when repetition of SDQ is less frequent (i.e., at lower SDQ rates), there will be no change in protocol performance (except in the case of PDP). However, when the SDQs are frequently repeated (i.e., at higher SDQ rates), performance of all protocols improves with the increase in CLT. Notice that the improvement in PDP’s performance is higher because any node in the MANET can benefit from the broadcasted SDY before the elapse of CLT