A Strategy for High Throughput in Ad Hoc Networks using Count Metric with Protocols

Pages:66-71
Sunil and Poonam (Research Scholars, Singhania University, Rajasthan)

A multi-hop wireless network is a network of computers and devices (nodes) which are connected by wireless communication links. The links are most often implemented with digital packet radios. Because each radio link has a limited communications range, many pairs of nodes cannot communicate directly, and must forward data to each other via one or more cooperating intermediate nodes. We will often use ‘hop-count metric’ to mean the minimum hop-count metric. The PTC of a route is the total number of packet transmissions and retransmissions required to send a packet across the route, assuming that each link in the route retransmits the packet until it is successfully received across the link. PTC is designed for links with link-layer acknowledgments (ACKs) and retransmissions, as provided by IEEE 802.11 radios. The PTC metric for a route is calculated using measurements of the lossless of each link in the route. Routing protocols select routes with the minimum PTC. For short routes (up to and including 3-hop routes), the minimum- PTC route is the maximum-throughput route; for longer routes, the minimum- PTC route is still a high-throughput route. The design of the PTC metric does not depend on a particular routing protocol; PTC improves the throughput of both Dynamic Source Routing (DSR), an on-demand source routing protocol, and Destination-Sequenced Distance-Vector (DSDV) routing, a proactive table-driven distance-vector routing protocol. We also present a set of design changes and implementation techniques that allow DSR and DSDV to work well with PTC.