CAN: Configurable Access Network for Maximizing the Life-Time of Static Ad-hoc Networks with QoS Guarantees

This work considers the problem of designing management algorithms for maximizing the lifetime of static multi-hop wireless networks, while ensuring QoS requirements such as bandwidth and delay. These networks are composed of a set of wireless stations where some of them, termed "access points", function as gateways to access a wired backbone. Since, in most cases, the wireless stations obtain their energy from consumed sources of energy, maximizing the network lifetime is a major concern in these systems. Our solution is based on a simple observation that these networks are usually used as access networks for gathering or dissemination of information, e.g. sensor networks. In spite of its simplicity, this compelling observation enables us to construct efficient systems with long lifetime, termed "configurable access networks" (CAN). Such a system utilizes a "network operation center" (NOC), exterior to the wireless network, for managing the system. The NOC selects a single route for each node that connects it with an access point. Then, it determines the packet scheduling along these routes for obtaining collision free operation. As a result, the CAN system maximizes the network lifetime while simplifying the task of network management. It also eliminates the need of complicated distributed management algorithms, which enables us to use very simple nodes. Since, the route selection and the packet scheduling problems are NP-hard, we presents approximation algorithms that provide guarantees on the network lifetime and the system throughput. Our simulations show that our algorithms find near optimal solutions.