Context Aware Quality of Service in Wireless Sensor Networks
Wireless sensor networks WSNs are typically deployed for monitoring and/or surveillance purposes, and the sensor nodes cooperate among themselves to achieve their common goals. However, for cooperation, Context Aware Quality of Service in .Wireless Sensor Networkssensor nodes are required to share information with their neighbors, which is facilitated by enabling communication among the nodes. Interestingly, Context Aware Quality of Service in Wireless Sensor Networks communication is a more energy consuming process than computation and sensing. The resource-constrained sensor nodes can use context awareness as a potential instrument for sharing information instead of doing it through direct communication. Context Aware Quality of Service in Wireless Sensor Networks Inferring required information through context awareness helps the sensor nodes conserve their precious battery power.
Concurrently, nodes can enhance, Context Aware Quality of Service in Wireless Sensor Networks through context awareness, the overall network performance by providing appropriate quality of service QoS to other nodes. An example is given next. In WSNs, after detecting an event, a sensor node increases its transmission rate so that it can communicate the maximum volume of information about the event. Moreover, Context Aware Quality of Service in Wireless Sensor Networks packets containing event information have higher priority than other packets. Instead of checking each packet for its priority, a relay node can infer the priority of the received packets from the transmission rate of their respective source nodes. Context Aware Quality of Service in Wireless Sensor Networks Before forwarding the received packets, a relay stores them in a queue.
Context Aware Quality of Service in Wireless Sensor Network
Here, the queue length is an important piece of context information. Context Aware Quality of Service in Wireless Sensor Networks A sudden increase in queue length indicates a relay that some of the descendents increase their transmission rate, and the packets from such descendents are of high priority. The QoS requirements of nodes of a WSN with respect to parameters such as end-to-end delay and jitter are application-specific, and also vary with time and location . Moreover, the inherent characteristics, such as resource constraints and network dynamism, of WSNs make the task of providing QoS support more challenging. Nevertheless, QoS-aware network management of a WSN ensures end-to-end performance guarantee while utilizing network resources efficiently. The QoS requirements of nodes change with time due to both spatial and temporal correlation. As sensor observations are spatially and temporally correlated, sensor nodes exploit spatial and temporal correlation to reduce the transmission of redundant data, and hence save battery power. Due to spatial correlation, it is not necessary for every sensor node to transmit its data. Furthermore, a sensor node does not need to transmit continuously because of temporal correlation.
Spatial correlation interrelates sensor nodes with a location or an area, whereas temporal correlation regulates the behavior or transmission rate of the nodes. The QoS support and exploitation of correlation enhance the effectiveness of a WSN. In a WSN, the QoS demand of nodes varies, andcorrelation differentiates the nodes into various categories. In this work, we use context awareness in an attempt to establish relationship between correlation and network QoS. Context-aware sensor nodes cooperate to provide differentiated services to the different categories of nodes without use of any complex mathematical model as advocated by Marchese and Mongelli in. The rest of the article is organized as follows. In the next section, the necessities of differentiated services in WSNs are discussed. After that, we illustrate the concepts of spatial and temporal correlation, and which contexts are associated with the correlations. After discussing the The data delivery models in a WSN are periodic, event-driven, query-initiated, or hybrid in nature. In the periodic delivery model.