On the potential of hybrid route/relay schemes

The objective of increasing capacity in mobile ad-hoc networks (MANETs) by exploiting the mobility of nodes has produced interesting but rather unrealistic results. The throughput improvement is not followed by reasonable delay performance, and in realistic settings there is a need to compensate for the potentially low mobility of all, or parts of, the network. We explore the throughput/delay tradeoff by attempting to utilize all possible service (transmission) opportunities that may exist. To this end, a measure of redundancy is introduced and its impact characterized. The definition of redundancy admits both the replication of data items as well as the traversal of paths. We study three schemes, where the third is a new proposal for a hybrid scheme that balances off a limited form of routing with relayed packet propagation. We find that the hybrid is resilient to the impact of mobility, providing good performance even at low mobility settings.