Traditional QoS routing protocols find paths that meet the QoS requirements while discovering routes. The chosen route is used while the QoS is met. If the QoS is violated rerouting takes place. Violation of QoS may be unacceptable for delay sensitive traffic. We introduce a preemptive QoS re-routing scheme. The end-to-end delay of packets in each session is monitored and if it seems likely that QoS violation might occur, a preemptive QoS rerouting process is initiated. This helps maintain QoS in dynamic wireless ad hoc networks. Schemes for triggering QoS re-routing are investigated. We have reduced the number of late packets and improved the overall end-to-end delay of the communications.
The Suburban Ad Hoc Network (SAHN) is a cooperative ad hoc wireless mesh network. Nodes are owned and operated by end-users without reliance on central infrastructure. It provides symmetrical bandwidth allowing peer-to-peer services and distributed servers. We minimize the use of scarce unlicensed RF spectrum supported by Smart Antenna technology. RF interference in such networks and techniques and strategies to reduce it are examined. Traffic is spread across multiple frequency channels, and multiple directional beams to achieve improved spatial re-use. We focus on the control of smart antennas rather than their design. By dynamically adjusting our network topology using Smart Antennas and dynamically re-routing current communications we optimize the network for its current traffic needs.