**2. Wireless sensor network design system**

### **2.1 Characteristics of a sensor network**

A wireless sensor network is a relatively large set of nodes called sensors. These sensors are very small devices scattered a little randomly in an area called "sensing region" (see **Figure 1**). The sensors are autonomous and have the role of collecting information (varied according to the field of application) [6, 12]. These will then be sent to an administrator via the gateway (well node) using appropriate routing techniques which we will see in another part. The well or sink node is the intermediate node between the administrator who is generally very far away and the whole network.

Indeed, when a sensor has to inform the administrator of an event or simply send the information collected, it must first pass this information to the sink. It is the latter that will transfer the said information to the administrator through an extensive network such as the Internet or more simply via the satellite [2, 4, 10].

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*Design Model and Deployment Fashion of Wireless Sensor Networks*

have to go through the sink in order to reach his targets [13].

Conversely, when it is now the administrator who wants to send information or requests to the various sensors of the 4th network or to one in particular, he too will

Thus, we have just seen that each sensor node will send its messages to the well node in order to inform the administrator [14]. However, it would be good to know that there are indeed two distinct types of communication architecture in a wireless

No particularity, the first hierarchical network is quite the simplest. All the sensor nodes have the same function and the same power except the well node which keeps its same function. it stipulates for the hierarchical network that the catchment area must be divided into several regions. Each region contains a number of normal sensor nodes added to these one or more nodes more powerful than the others. These sensors will act as a routing gateway between the different regions. This type of infrastructure makes it possible to offload the less powerful (and

So, we just saw the architecture of a wireless sensor network, defining the overall way of communication between the nodes and the administrator. But we still do not know how we go from an event to information sent to the user. In order to try to answer this, we can see below the hardware architecture of a deep sensor node. The basic objectives of wireless sensor networks generally depend on the applications; however, the following tasks are common to several applications:

• Determine the values of some parameters according to a given situation. For example, in an environmental network, one can seek to know the temperature, the atmospheric pressure, the amount of sunlight, and the relative humidity in

• Detect the occurrence of events that we are interested in and it estimates the parameters of the events detected. In traffic control networks, one may want to detect the movement of vehicles through an intersection and estimate the

• Classify the object detected, e. g in a traffic network is a vehicle a car, a bus,

In general, WSN is formed by sensor nodes. It is responsible for examining environmental and corporal conditions to perform data processing. It is considered as a special type of ad hoc network where the fixed communication infrastructure and centralized administration are absent routers [16]. The sensor nodes form a network of sensors and the nodes play both; the role of hosts, and they are smart. Sensors are capable of accomplishing three complementary tasks: the reading of a physical quantity, the possible processing of this information, and the communication with other sensors. They are deployed to accomplish an application. Typically, they can be rapidly deployed and distributed over a geographical area in a multi-hop packet radio communication network without the help of an established infrastructure as it is

therefore less expensive) nodes of several network functions [13, 14].

*DOI: http://dx.doi.org/10.5772/intechopen.94256*

sensor network. That are:

• The flat network

• The hierarchical network:

a number of sites, etc. [6].

etc. [12, 15].

shown in **Figure 2**.

speed and the direction of the vehicle [15].

And

**Figure 1.** *WSN elements considered into the network.*

#### *Design Model and Deployment Fashion of Wireless Sensor Networks DOI: http://dx.doi.org/10.5772/intechopen.94256*

Conversely, when it is now the administrator who wants to send information or requests to the various sensors of the 4th network or to one in particular, he too will have to go through the sink in order to reach his targets [13].

Thus, we have just seen that each sensor node will send its messages to the well node in order to inform the administrator [14]. However, it would be good to know that there are indeed two distinct types of communication architecture in a wireless sensor network. That are:

• The flat network

And

*Wireless Sensor Networks - Design, Deployment and Applications*

**2. Wireless sensor network design system**

**2.1 Characteristics of a sensor network**

design factors: network efficiency and lifetime greatly depend on the quality of the protocols used. So, routing in WSN must proceed to the formation of new routes between the nodes in case the failure of communication links [8, 9]. It turns out that, efficiency in energy consumption represents a significant performance factor that limits node capacity. They are limited in memory of their major constraint but cheaper. They have limited available power because there are depleting their energy in sense as well as in communicating the signal to the base station because communication needs more power than data processing [4, 10]. Therefore, computing [4, 8, 11] resources and batteries are more limited in sensor nodes than in ad hoc nodes. Indeed, to develop this system architecture, it is necessary to start from the high-level requirements for the realization of the requested application, then to the low-level hardware requirements. In this chapter, the focus is on the communication strategy about the Design model and deployment fashion of the wireless node. It is organized as follows: Section2 gives an overview of the wireless sensor network design system, the different sensor network elements are shown in Section3, Section4 explains the deployment model of nodes, Section5 presents the vulnerabilities and challenges in WSN. We will show many areas of application of the WSN in which they are used. And finally, the conclusion is provided in

A wireless sensor network is a relatively large set of nodes called sensors. These sensors are very small devices scattered a little randomly in an area called "sensing region" (see **Figure 1**). The sensors are autonomous and have the role of collecting information (varied according to the field of application) [6, 12]. These will then be sent to an administrator via the gateway (well node) using appropriate routing techniques which we will see in another part. The well or sink node is the intermediate node between the administrator who is generally very far away and the whole

Indeed, when a sensor has to inform the administrator of an event or simply send the information collected, it must first pass this information to the sink. It is the latter that will transfer the said information to the administrator through an extensive network such as the Internet or more simply via the satellite [2, 4, 10].

**42**

**Figure 1.**

*WSN elements considered into the network.*

Section 7.

network.

• The hierarchical network:

No particularity, the first hierarchical network is quite the simplest. All the sensor nodes have the same function and the same power except the well node which keeps its same function. it stipulates for the hierarchical network that the catchment area must be divided into several regions. Each region contains a number of normal sensor nodes added to these one or more nodes more powerful than the others. These sensors will act as a routing gateway between the different regions. This type of infrastructure makes it possible to offload the less powerful (and therefore less expensive) nodes of several network functions [13, 14].

So, we just saw the architecture of a wireless sensor network, defining the overall way of communication between the nodes and the administrator. But we still do not know how we go from an event to information sent to the user. In order to try to answer this, we can see below the hardware architecture of a deep sensor node.

The basic objectives of wireless sensor networks generally depend on the applications; however, the following tasks are common to several applications:


In general, WSN is formed by sensor nodes. It is responsible for examining environmental and corporal conditions to perform data processing. It is considered as a special type of ad hoc network where the fixed communication infrastructure and centralized administration are absent routers [16]. The sensor nodes form a network of sensors and the nodes play both; the role of hosts, and they are smart. Sensors are capable of accomplishing three complementary tasks: the reading of a physical quantity, the possible processing of this information, and the communication with other sensors. They are deployed to accomplish an application. Typically, they can be rapidly deployed and distributed over a geographical area in a multi-hop packet radio communication network without the help of an established infrastructure as it is shown in **Figure 2**.

**Figure 2.** *WSN architecture [6, 17, 18].*

Since wireless sensor nodes are usually very small electronic devices. It has been considered as a special type of ad hoc network. It brings an interesting perspective (**Figure 3**). This kind of network is capable of self-configuring and self-managing without the need for intervention human. One of the main design objectives of the WSNs is realizing communication data while trying to extend the lifetime of the network and prevent the degradation of connectivity by using energy management techniques. Low energy nodes are used to perform detection in the area of interest. However, wireless transmission is a significant simplification that can avoid a lot of wiring. Its main advantage is the capacity for self-managing and self-configuring without the need for human intervention. The nodes cooperate and communicate

**45**

*Design Model and Deployment Fashion of Wireless Sensor Networks*

with each other to transmit the data to each other in the WSN network as seen in **Figure 1**. Hence, these two communicative nodes as shown in the same figure

Thus, we have just seen that each sensor node will send its messages to the well-Known Base station as expected in WSN architecture we must have one destination. In order to inform the administrator or the end user. However, it would be good to know that there are indeed two distinct types of communication architecture in a wireless sensor network. There are two types in WSN (Flat and Hierarchical

These sensors nodes determine the route/path by routing packets using various routing protocols [2, 9]. Nodes of the WSN network maintain connectivity in a distributed way. This topology instability needs a routing protocol to be run in each node to create and maintain routes between nodes. One of the main design objectives of the WSNs is to realize communication data while trying to extend the lifetime of the network and prevent the degradation of connectivity by using energy management techniques [8, 18]. The Designing security protocols require understanding these limits (sensors in terms of energy, memory, computing

capacity) and achieving acceptable performance with security measures to meet the needs of an application. The design of security protocols requires understanding these limits of WSNs and achieving acceptable performance with security measures to meet the needs of an application [12, 13, 15]. Preferentially, the node should be able to enter and leave the network even if the design, implementation, and configuration are correct, resource depletion is possible. This is why WSNs are classified into infrastructure-less networks. Moreover, their ease deployment in the harsh and hard environment possesses a paved to the way for it. Their capacity on gathering information from surrounding is very helpful to improve the quality of living, as it makes life easy because of modern technology in our daily life [4, 10, 11]. The manner of deployment of WSN will be presented in this chapter, and how they are communicated over a wireless link to unite the necessities of a specific application that will be shown. There are a lot of factors that are included the organization of wireless sensor networks that are: network organization, number of nodes, number of routers, network topology, and geographical distribution [8, 18]. They have been recently attracted a lot of interest in the research community due to their wide range of applications. In this way, we can choose any kind of sensors to be used for a specific purpose such logistics, smart agriculture, industrial controls, smart home, military target tracking, and security monitoring. This chapter will describe the

Nowadays, Wireless technologies have been developed rapidly, and Wireless sensor networks (WSNs) are one of them [2, 4]. A deployment of several devices equipped with sensors and it has been considered as a special type of ad hoc network that brings an interesting perspective. It can be rapidly deployed by a set of wireless computers in a multi-hop packet radio communication network without the help of established infrastructure [14, 16]. Or, it can only be equipped with limited power and wireless sensor nodes can perform a collaborative measurement process. In this network, the use of wireless transmission in the open-air medium remains the most important thing to make information accessible for the user. In brief, Wireless ad-hoc networks can be used in special areas where wired network

*DOI: http://dx.doi.org/10.5772/intechopen.94256*

(**Figure 1**) are called a one-hop neighbor.

**2.2 Path selection in WSN**

architecture) that we will see in the next section.

design, deployment, and applications in WSN [18, 19].

**2.3 Difference between sensor and ad hoc network**

**Figure 3.** *Sensors-tasks [3–5, 7].*

with each other to transmit the data to each other in the WSN network as seen in **Figure 1**. Hence, these two communicative nodes as shown in the same figure (**Figure 1**) are called a one-hop neighbor.

Thus, we have just seen that each sensor node will send its messages to the well-Known Base station as expected in WSN architecture we must have one destination.

In order to inform the administrator or the end user. However, it would be good to know that there are indeed two distinct types of communication architecture in a wireless sensor network. There are two types in WSN (Flat and Hierarchical architecture) that we will see in the next section.

#### **2.2 Path selection in WSN**

*Wireless Sensor Networks - Design, Deployment and Applications*

Since wireless sensor nodes are usually very small electronic devices. It has been considered as a special type of ad hoc network. It brings an interesting perspective (**Figure 3**). This kind of network is capable of self-configuring and self-managing without the need for intervention human. One of the main design objectives of the WSNs is realizing communication data while trying to extend the lifetime of the network and prevent the degradation of connectivity by using energy management techniques. Low energy nodes are used to perform detection in the area of interest. However, wireless transmission is a significant simplification that can avoid a lot of wiring. Its main advantage is the capacity for self-managing and self-configuring without the need for human intervention. The nodes cooperate and communicate

**44**

**Figure 3.**

**Figure 2.**

*WSN architecture [6, 17, 18].*

*Sensors-tasks [3–5, 7].*

These sensors nodes determine the route/path by routing packets using various routing protocols [2, 9]. Nodes of the WSN network maintain connectivity in a distributed way. This topology instability needs a routing protocol to be run in each node to create and maintain routes between nodes. One of the main design objectives of the WSNs is to realize communication data while trying to extend the lifetime of the network and prevent the degradation of connectivity by using energy management techniques [8, 18]. The Designing security protocols require understanding these limits (sensors in terms of energy, memory, computing capacity) and achieving acceptable performance with security measures to meet the needs of an application. The design of security protocols requires understanding these limits of WSNs and achieving acceptable performance with security measures to meet the needs of an application [12, 13, 15]. Preferentially, the node should be able to enter and leave the network even if the design, implementation, and configuration are correct, resource depletion is possible. This is why WSNs are classified into infrastructure-less networks. Moreover, their ease deployment in the harsh and hard environment possesses a paved to the way for it. Their capacity on gathering information from surrounding is very helpful to improve the quality of living, as it makes life easy because of modern technology in our daily life [4, 10, 11]. The manner of deployment of WSN will be presented in this chapter, and how they are communicated over a wireless link to unite the necessities of a specific application that will be shown. There are a lot of factors that are included the organization of wireless sensor networks that are: network organization, number of nodes, number of routers, network topology, and geographical distribution [8, 18]. They have been recently attracted a lot of interest in the research community due to their wide range of applications. In this way, we can choose any kind of sensors to be used for a specific purpose such logistics, smart agriculture, industrial controls, smart home, military target tracking, and security monitoring. This chapter will describe the design, deployment, and applications in WSN [18, 19].

#### **2.3 Difference between sensor and ad hoc network**

Nowadays, Wireless technologies have been developed rapidly, and Wireless sensor networks (WSNs) are one of them [2, 4]. A deployment of several devices equipped with sensors and it has been considered as a special type of ad hoc network that brings an interesting perspective. It can be rapidly deployed by a set of wireless computers in a multi-hop packet radio communication network without the help of established infrastructure [14, 16]. Or, it can only be equipped with limited power and wireless sensor nodes can perform a collaborative measurement process. In this network, the use of wireless transmission in the open-air medium remains the most important thing to make information accessible for the user. In brief, Wireless ad-hoc networks can be used in special areas where wired network

infrastructure may be unsuitable. (Or a wired network infrastructure may not be suitable for reasons such as cost or convenience [3].

In ad hoc mobile networks (MANETS) the nodes usually cooperate and transmit packets to each other to allow communication out of range (out of range). The nodes in WSNs rely on other nodes to transfer their packets [5]. The difference between both Wireless sensor network and Ad hoc network in the following:


#### **3. The different sensor network elements**

Recent findings on empirical studies have deduced that radio links between low-power sensing devices are far from being reliable. This why making a model that is akin to the reality of radio communication channels is something out of reach or at least very challenging [2, 8]. Computing nodes (usually wireless) in an ad hoc network act as routers to deliver messages between nodes that are not within their wireless communication range [1, 7]. Because of this unique capability, mobile ad hoc networks are envisioned in many critical applications (e.g., in battlefields). Therefore, these critical ad hoc networks should be sufficiently protected to achieve confidentiality, integrity, and availability. Wireless sensors are typically low-power, low-cost, and short-range minuscule devices. Multi routes rely on data from the monitored region to the sink. The measuring nodes are a wireless device, they usually cooperate and transmit packets to each other to allow communication out of range, they rely on other nodes to transfer their packets. Preferentially, the node should be able to enter and leave the network [12, 13]. The self-organizing capability makes them flexible for communication in areas [6].

But in fact, resource depletion is possible even if the design, implementation, and configuration are correct [15]. Or, it can only be equipped with limited power. In WSN. The nodes usually cooperate and transmit packets to each other to allow communication out of range [18]. That's why Multi-hop routes are needed to transfer data from node to another in the network. The tasks that the sensors can perform are shown in **Figure 1**. Every single node in the network must be able to perform these different tasks. Every single node should be made to give a set of basic primitives to combine the interconnected web that will appear as they are scattered. Since sensor nodes are: -small distributed, they may be on a large scale or in a dangerous area [8, 19]. Their battery is small and it maybe not recharged or replaced. So, the network lifetime is prolonged when the battery energy is used wisely. Individual nodes interact with the environment in which they are scattered to perform the functions dictated by the sensor network applications [1, 4, 11]. They focus on interaction with the environment instead of focusing on interaction with humans [10]. So, it can be said that in the hardware architecture of the wireless sensor network has four basic subsystems of sensor nodes:

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*Design Model and Deployment Fashion of Wireless Sensor Networks*

*DOI: http://dx.doi.org/10.5772/intechopen.94256*

• Computing subsystem

• Power subsystem

*Sensing node design [5, 6, 14, 17].*

**Figure 4.**

• Sensing subsystem

• Communication subsystem

**4. Architecture of a sensor node**

• A collection unit

• A processing unit

• A transmission unit

• An energy management unit

Concerning software architecture, a wireless sensor is a device consisting of a data acquisition unit using a sensor of a physical quantity + (processing) + transmission by wireless technology. A wireless sensor network is a set of sensors grouped within the same wireless network [12, 14]. They are considered as a special type of ad-hoc network composed of "nodes." These nodes form a catchment field and routing that is using routing protocols which are in star or hybrid form, to an end-user which is the sink it is finally a user request. They have limited available power because there are depleting their energy in sense as well as in communicating the signal to the base station Therefore, computing resources and batteries are more limited in sensor nodes than in ad hoc nodes. A standard sensor type-TelosB has a 16-bit, 8 MHz RISC CPU with 10 K RAM, 1024 K flash storage and 48 K program memory [13–15]. The general

Advances in miniaturization have enabled sensors to integrate several modules despite their relatively small size. They mainly consist four (4) units [14, 17, 18]:

In addition to these, we can find depending on the field of application of the sensor network, a unit for localization, the unit for movement, and sometimes the unit for producing energy thanks to small solar panels. The diagram in **Figure 4**

overall software architecture of the sensor net is shown in **Figure 4**.

*Design Model and Deployment Fashion of Wireless Sensor Networks DOI: http://dx.doi.org/10.5772/intechopen.94256*

**Figure 4.**

*Wireless Sensor Networks - Design, Deployment and Applications*

suitable for reasons such as cost or convenience [3].

infrastructure may be unsuitable. (Or a wired network infrastructure may not be

packets to each other to allow communication out of range (out of range). The nodes in WSNs rely on other nodes to transfer their packets [5]. The difference between both Wireless sensor network and Ad hoc network in the following:

• The density of deployed nodes is much higher in sensor networks

• The sensor nodes have limited capacity in energy and memory

• The topology in sensor networks is often dynamic.

capability makes them flexible for communication in areas [6].

**3. The different sensor network elements**

network of sensors.

In ad hoc mobile networks (MANETS) the nodes usually cooperate and transmit

• Communication between the nodes is by diffusion and not point to point in a

• Sensors may not have a global identifier due to a large number of nodes.

Recent findings on empirical studies have deduced that radio links between low-power sensing devices are far from being reliable. This why making a model that is akin to the reality of radio communication channels is something out of reach or at least very challenging [2, 8]. Computing nodes (usually wireless) in an ad hoc network act as routers to deliver messages between nodes that are not within their wireless communication range [1, 7]. Because of this unique capability, mobile ad hoc networks are envisioned in many critical applications (e.g., in battlefields). Therefore, these critical ad hoc networks should be sufficiently protected to achieve confidentiality, integrity, and availability. Wireless sensors are typically low-power, low-cost, and short-range minuscule devices. Multi routes rely on data from the monitored region to the sink. The measuring nodes are a wireless device, they usually cooperate and transmit packets to each other to allow communication out of range, they rely on other nodes to transfer their packets. Preferentially, the node should be able to enter and leave the network [12, 13]. The self-organizing

But in fact, resource depletion is possible even if the design, implementation, and configuration are correct [15]. Or, it can only be equipped with limited power. In WSN. The nodes usually cooperate and transmit packets to each other to allow communication out of range [18]. That's why Multi-hop routes are needed to transfer data from node to another in the network. The tasks that the sensors can perform are shown in **Figure 1**. Every single node in the network must be able to perform these different tasks. Every single node should be made to give a set of basic primitives to combine the interconnected web that will appear as they are scattered. Since sensor nodes are: -small distributed, they may be on a large scale or in a dangerous area [8, 19]. Their battery is small and it maybe not recharged or replaced. So, the network lifetime is prolonged when the battery energy is used wisely. Individual nodes interact with the environment in which they are scattered to perform the functions dictated by the sensor network applications [1, 4, 11]. They focus on interaction with the environment instead of focusing on interaction with humans [10]. So, it can be said that in the hardware architecture of the wireless sensor network has four basic subsystems

**46**

of sensor nodes:

*Sensing node design [5, 6, 14, 17].*


Concerning software architecture, a wireless sensor is a device consisting of a data acquisition unit using a sensor of a physical quantity + (processing) + transmission by wireless technology. A wireless sensor network is a set of sensors grouped within the same wireless network [12, 14]. They are considered as a special type of ad-hoc network composed of "nodes." These nodes form a catchment field and routing that is using routing protocols which are in star or hybrid form, to an end-user which is the sink it is finally a user request. They have limited available power because there are depleting their energy in sense as well as in communicating the signal to the base station Therefore, computing resources and batteries are more limited in sensor nodes than in ad hoc nodes. A standard sensor type-TelosB has a 16-bit, 8 MHz RISC CPU with 10 K RAM, 1024 K flash storage and 48 K program memory [13–15]. The general overall software architecture of the sensor net is shown in **Figure 4**.
