Introduction Of Wireless Sensor Networks

Processor:It is considered as heart of the computer which controls all the operations of the computer and data processing.

A WSN is a type of wireless networks that consists of collection sensor nodes which are tiny devices. Each sensor node of the network has different processing capability. It may contain multiple types of memory (program, data and flash memories), have a RF transceiver, have a power source (e.g., batteries and solar cells), and accommodate various sensors and actuators. The nodes communicate wirelessly and often self-organize after being deployed in an ad hoc fashion [13, 14]. Optimum need of each sensor node is to maximize its own utility function. Also the whole network requires resource assignments balance to perform in a useful and efficient way. This chapter presents a brief survey on WSNs showing its types, characterizing features, protocols and applications.

3. The __ Processing Unit is a hardware component capable of quickly drawing items to the screen. Graphical Processing Unit

Processing unit: It consists of a processor (microcontroller) and storage (RAM). In addition, it has operating systems as well as a timer. The responsibility of the processing unit includes collecting data from various sources then processing and storing. A timer is used to do the sequencing for the processes. This is basically where the

Nowadays, Wireless sensor networks (WSNs) are getting more and more involved in our society, researchers and manufacture. As the use of WSNs increases the more challenges rise to make them immune and life longer. Therefore, both fields industry and academia invest money to improve the capability of the security integrity, confidentiality, and authentication. Since WSNs are distributed in unfrequented and abandoned venues, the physical security is unconcerned or less concern. The most concern is the lifetime of Wireless sensor networks, sensors have limited source of power. Thus, economizing energy will keep sensors live longer, the less power means more efficiency. Moreover, secure data is important as well, since no one attends where sensors are located, it is easy to manipulate data or steal it. Cryptography provides high security to WSNs, using algorithms to encrypt and decrypt the sent data is

There are generally 2 types of architectures in WSNs. (i) Hierarchical and (ii) Distributed. In a Hierarchical WSN, A base station is a gateway to another network with some other base station to a data processing and storage center, or a human interface node point. Base point takes data from sensors send it to processing unit and that data is sent to the human interface node point. Therefore, base stations are used as key distribution centers as they are connected every other node in network. Sensor nodes form a dense network in form of clusters where a cluster of sensors lying in a specific area may provide similar or close readings of data. Not all node gets the power from power unit few sensor nodes depend on the ad hoc communication to reach base stations.

For achieving this goal, physical deployment of the nodes and the sample periods are pre-determined by the scientists. To ensure that data is delivered as expected is the real role of the network. For achieving this goal it is necessary to reduce the network complexity as much as possible from the services and its application. It is possible to optimize communication performance for that application-not for a generic set of users as each node executes a single application. For achieving this it is necessary to translate them into a set of goals for media access protocol to satisfy the requirement of wireless sensor network deployment and monitoring application. For WSNs application, the common goals for a MAC protocol are:

A compute unit (CU) is composed of one or more processing elements and local memory.

A wireless sensor network (WSN) is a collection of large number of sensor nodes and at least one base station. The sensor node is an autonomous small device that consists of mainly four units that are sensing, information gathering, processing and communication. In wireless sensor network there of many issues that are much affects in communication, processing and in deployments. The main issue is its coverage and connectivity problem. Most of the times communications does not prohibited properly amongst sensors and base station due lacking of ranges problem. Full coverage and connectivity means that every location in the field is covered by at least one node and

Wireless sensor networks are usually deployed in infrastructure-less environment with the sensor nodes themselves being battery powered (low powered) devices so, data aggregation is an attractive method to reduce the power requirements of the individual sensor nodes that sense, record and transmit the data about their surroundings. Data aggregation may refer to any number of methods that allow for the reduction of the volume of data that the sensor nodes must exchange by combining data from multiple sources and removing redundancies, thereby reducing the power consumption by the sensor nodes.

Abstract: Wireless sensor networks (WSN) have grabbed much attention in recent years due to their potential use in many applications. One such application is deploying WSN in underground mines to monitor the miner 's physical signals as well as the environment they are exposed to. However, due to the resource constraints of sensor nodes and the adhoc-formation of the network, in addition with an unattended deployment, pose un-conventional demands provoke the need for special techniques for design and management of WSN. Because of the restrictions caused by the lossy dielectric walls and ceilings in the underground mines, the radio signal propagation characteristics are significantly different from those of terrestrial wireless channels. In this paper, underground WSN is designed considering worker’s safety in under-ground, increased energy efficiency and productivity as main goals.

In many application areas, the wireless sensor network must be able to operate for long periods of time, and the energy consumption of both individual sensor nodes and the sensor network as a whole is most important. Thus energy consumption is an important issue for wireless sensor networks. Figure 1 shows the architecture of wireless sensor network. It consists of one sink node (or base station) and a (large) number of sensor nodes deployed over a

Abstract: Wireless Sensor Network is a collection of homogeneous/heterogeneous wireless devices used to monitor the changes in the surrounding of the wireless device. Each wireless device present in the network has the capability of sensing the changes in the surrounding environment. Homogeneous sensors are those which have same computational power, energy etc. Each node is battery powered which is used to transmit the sensed data over the network. So efficient transmission of data in Wireless Sensor Network is important and to transmit the data unaltered over the network to the receiver security is important

Processing core consists of the data processor (calculations, flow control program, etc.) and administration of peripherals.

Current the new arrival of generation of wires sensor network has been provided for several applications because of modern period which brought the integration of the smallest physical sensors, embedded of small controllers called microcontrollers and radio interfaces on one and only single chip fabrication. All of these functions brought a wide range of application for sensor networks. The integration into wearable wires body area network has been incorporated with a big number of physiological sensors. In addition the idea of micro-sensing and wires and wires linked to the network nodes promises several new application areas like, health ,home, environment ,sport house and others. We briefly illustrate these applications and for more details, the reader should refer to [29].