Comparative Analysis of the Extended Persistence Policy on Distance-Vector and Link-State Routing Performance in the DOUNG Ad Hoc Network

In this paper, we examine how the VTP2 extended persistence timeout policy affects and influences the performance of distance-vector and link-state routing protocols in the ad hoc network of the New Generation of Open Digital Universities (DOUNG). The problem addressed is that conventional SCTP retransmissions lack good performance when losses result from a path break rather than congestion. In classical SCTP, missing acknowledgments may trigger retransmissions even when the loss is caused by a temporary route failure rather than by congestion. The proposed evaluation uses an NS-3-compatible methodology with IEEE 802.11, SCTP, AODV, DSDV, DSR and OLSR under increasing node mobility. Results are organized by protocol to improve figure readability. The reference outputs show that VTP2 improves packet delivery ratio, throughput, end-to-end delay, SCTP retransmissions and energy consumption. The average gains are higher for AODV, DSDV and DSR than for OLSR, confirming that extended persistence is more beneficial to protocols exposed to route discovery, repair and maintenance phases. These results indicate that VTP2 is a relevant cross-layer mechanism for improving quality of service in mobile, heterogeneous and distributed digital-university environments.