*3.2.3 TEEN – (threshold sensitive energy efficient sensor network protocol)*

TEEN is a hierarchical clustering protocol that binds sensor nodes and forms a cluster of nodes where each node of the cluster is operated by CH. In this CH collects data from their member node and then forwards it to their higher CH node, the CH aggregates the data and delivers to the sink node. In this scenario, at each cluster varies with the time where the CH broadcast threshold value to its member nodes [20, 21].

	- i. The value of the current sensed attribute must be higher than the hard threshold value.

```
Scurrent > Hcuttoff ðCondition 1Þ
```
ii. The value of the current sensed attribute must vary from the stored sensed value, and its difference value should be equal or greater to the soft threshold value.

$$(\mathcal{S}\_{current} \neq \mathcal{S}\_{stored}) \geq \mathcal{S}\_{cutoff} \quad (Condition\ 2)$$

Whenever these conditions are met, the hard-cutoff attempts to minimize the burden of transmissions by permitting the sensor nodes to forward data only when the sensed attribute exists in the area of interest.

The above **Figure 6** demonstrates, the time line operation of TEEN protocol where it represents a little variation in the sensed attributes value and allow to sensor nodes to become active form sleep mode in order to forward the data to CH. Therefore, if the value of the sensed attribute does not change or changes minimally, the soft cutoff value will reduce the transmission load of the sensed data. Based on the hard-cutoff value, the node will only transmit the sensed data according to end user requirement and resulting in more energy preservation through making changes relative to earlier data report. When the next cycle initiates, the CH is to be changed, then a new value of parameters broadcasts.

TEEN is very practical for the user interactive applications where a user can dynamically control energy efficiency and perform trade-offs between the data accuracy, reliability and its response time. In this, Clustering formation process uses a layered approach as well as data-centric approach. The key feature of this protocol is that it is ideal for the real-time operated applications. Therefore, TEEN is best considered to be used in the reactive network because it saves power consumption during communication and data transmission. Also a critical drawback of this protocol is that if the threshold is not reached, then user will not be able to obtain any data packets.

• **Advantages of TEEN Protocol**

*Energy Saving Hierarchical Routing Protocol in WSN DOI: http://dx.doi.org/10.5772/intechopen.93595*

**Figure 7.**

**165**

*Clustering process in TEEN.*

• **Disadvantages of TEEN Protocol**

slots allotment.

may be useless.

transmitter continuously open.

i. This protocol is most suitable for the time-dependent applications.

iii. It also saves the energy through hierarchical clustering mechanism.

identification, and explosion detection, and also allows performing a

i. For vdata transmission, process, nodes may have to wait for their time

ii. If the node has no data to transmit, the time slot assigned to the node

iii. The cluster head always looks for data that causing its receiver

*3.2.4 APTEEN – (adaptive threshold sensitive energy efficient sensor network protocol)*

APTEEN was introduced as an improved version of TEEN to enhance the performance of the TEEN protocol to support the regular data collection process. The architecture of APTEEN is similar to the architecture of TEEN. APTEEN also follows a hierarchical clustering approach to achieve energy efficient communication between source sensors and receivers (SINK nodes). An enhanced feature of this protocol is that it allows the node to periodically transmit its sensed data, and if any rapid variations are found in the sensed attributes, then the sensor accordingly respond its report to CH. In this version, CH is also responsible for performing data aggregation operations to reduce power consumption in data processing tasks. Once

ii. It allows users to dynamically control response times, intrusion

tradeoff between energy efficiency and data accuracy.

• Cluster formation in TEEN

In this protocol, CH basically follows the concept of LEACH. In TEEN, first a cluster is formed; afterwards CH is selected by its member nodes. The CH broadcasts two threshold values to all of its member nodes. This process will continue for each cluster change time. The clustering and data collection process in TEEN is shown in **Figure 7**, where clusters are formed in a hierarchical arrangement, with CH and cluster nodes and data shared to the sink nodes through higherposition CHs.

**Figure 6.** *Operation of TEEN protocol.*

*Energy Saving Hierarchical Routing Protocol in WSN DOI: http://dx.doi.org/10.5772/intechopen.93595*

**Figure 7.** *Clustering process in TEEN.*
