Understanding the Interaction between Packet Forwarding and Channel Access in Multihop Wireless Networks

We proposed an analytical model to study the interplay between medium access control (MAC) and packet forwarding disciplines in multihop wireless networks. The model jointly considers the channel access procedure and the active portions of the topology, which is determined by packet forwarding discipline. The model allows the computation of per-node performance metrics for any given network topology and the combination of specific MAC protocols and packet forwarding methods. As an example of the applicability of our modeling framework, the analytical model is used to study the performance of multihop wireless networks using a contention-based MAC protocol (the IEEE 802.11 distributed coordination function) and a schedule-based MAC protocol (NAMA), together with different packet forwarding schemes in multihop networks. The analytical results derived from the model are validated with discrete-event simulations in Qualnet; the analytical results are shown to be very close to those attained by simulations.