Quality of Service Based Minimal Latency Routing for Wireless Networks
Abstract : Minimized and nearly deterministic end-to-end latency facilitates real-time data acquisition and actuator control. In addition, defined latency is an integral part of quality oriented service in order to get closer to the reliability of wired networks and at the same time take advantage of wireless networking. This paper introduces a QoS routing protocol capable of balancing power consumption between wireless sensor and actuator nodes while minimizing end-to-end latency. We introduce a TDMA scheme in the routed wireless network to enable defined latency and in addition it improves the energy efficiency by avoiding collisions which eliminates time and energy consuming retries. Our novel routing method allows latency and round-trip times to be calculated in advance. We implemented a demonstrator and show experimental results of a wireless sensor network with our proposed routing scheme.
? The algorithm is simulated on network simulator ns-2 and its performance is compared with an existing protocol.
? Recent convergence of technological and application trends has resulted in an exceptional level of interest in wireless adhoc networks and in particular in wireless sensor networks (WSNs).
? In situations where the amount of data to be exchanged is small and the quality of the paths is not important, an alternative technique is rumor routing.
? An agent emanates out of each node and propagates the data or interest. As the agents move, the corresponding data is stored in all nodes that the agents pass through.
? While these algorithms iteratively update the weighted cost in finding optimal routes in a graph, they show to be problematic in case of network fluctuations and failures due to the learning adaptation methodology, thus increasing energy consumption and reducing network lifetime significantly.
? To overcome the resulting problems, concepts for synchronization and determining the wake-up interval are adapted according to, which enables synchronicity of ±1 clock period.
? We focus on the impact of various design parameters on the performance of the routing algorithm.
? We first look at the impact of the SNR threshold on the network discovery phase and evaluate the number of layers that are necessary to maintain a given SNR threshold.
• In this paper, a query-based adaptive routing protocol is proposed that can satisfy multiple QoS requirements such as reliability and latency.
• Several properties of the proposed routing algorithm have been presented and the effectiveness of the protocol has been demonstrated by extensive simulations.
• In contrast to most of the current algorithms, the proposed algorithm does not attempt to optimize on a single parameter e.g., energy, latency and reliability.
• However, the proposed protocol will work even is situations where in-network processing and data aggregation is done at some intermediate sensor nodes.
? These imperfections in the wireless medium result in performance degradation and restrict the quality of service (QoS) for IWSN applications.
? In particular, the focus has been on the design and development of medium access control (MAC) protocols that improve the network performance .
? In more complex multi-hop networks, routing algorithms become crucial as they determine routes and channels for the transmission as well as the redundancy policy, and in this manner directly affect the aforementioned performance metrics.
? The QoS aspect is crucial in providing a guaranteed endto-end performance and it is especially demanded for real-time applications.
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