طولانی کردن عمر شبکه با استراتژی های همکاری چند دامنه در شبکه های حسگر بی سیم

In wireless sensor networks nodes forward the data they acquire from the environment towards the base station by relaying through multiple intermediate sensor nodes used as relays. If multiple sensor networks are deployed in close proximity then they can help each others’ data forwarding so that all parties involved in such cooperation benefit from this collaborative effort (i.e., energy consumption for packet relaying reduces and the lifetime of each network is prolonged). There are many parameters that affect the impact of cooperation on sensor network lifetime such as number of domains, node density, network area, propagation environment, network topology, and base station deployment. In this paper we investigate cooperation strategies for prolonging sensor network lifetime in multi-domain wireless sensor networks through a linear programming framework. While our model is detailed enough to capture the essence of the multi-domain cooperation we intentionally avoid implementation specific details. Hence, we use our framework to determine almost achievable performance benchmarks in idealized yet practical settings. Our results show that under certain conditions (sparse network deployment and harsh propagation environment) multi-domain cooperation can extend the wireless network lifetime more than an order of magnitude when compared to non-cooperating domains of wireless sensor networks.

In wireless adhoc networks, packets are transmitted from a source to a destination by relaying through multiple intermediate nodes acting as relays. The network is self-organized and there are no task-specific nodes like routers as in wired networks responsible for routing and forwarding or access points as in wireless networks working in infrastructure mode that orchestrate the communication

In this paper we investigated the potential benefits of utilizing multi-domain collaborative wireless sensor networks paradigm, which is an emerging new concept within the wireless sensor networks research. We formulated a linear programming framework to quantitatively evaluate the performance of various multi-domain cooperation strategies. In our framework the design objective is to maximize the network lifetime, which is defined as the time until first sensor node drains out its limited energy (i.e., battery). In our model all sensor nodes create equal amount of data per unit time and the data is collected by the sink(s). Nodes are permitted to forward their packets towards the base station(s) either directly or through multiple hops. Nodes dissipate energy only for data transmission or reception. Energy dissipation on reception is independent of the distance between the source and destination whereas in transmission energy dissipation is a function of the nodes separation. The results of our analysis are itemized as follows: