THRESHOLD SENSITIVE HETEROGENOUS ROUTING PROTOCOL FOR BETTER ENERGY UTILIZATION IN WSN

International Journal of Advanced Smart Sensor Network Systems (IJASSN), Vol 5, No.3/4, October 2015
DOI:10.5121/ijassn.2015.5402 11
THRESHOLD SENSITIVE HETEROGENOUS
ROUTING PROTOCOL
FOR BETTER ENERGY UTILIZATION IN WSN
Rajesh Kumar Yadav 1
and Ram Kumar 2
1
Computer Science and Engineering, Delhi Technological University Delhi, India
2
Computer Science and Engineering, Delhi Technology University Delhi, India
ABSTRACT
Advancements in WSN have led to the wide applicability of sensor network in various fields. WSNs basic
classification is Reactive and Proactive network. Reactive networks responds to the very immediate
changes in its environment in required parameters of interest, as opposed to the Proactive network, due to
continuous sensing nature of WSN. To make it more efficient and improved in terms of Energy in network’s
lifetime, we need to reduce the energy expense in the network model, which is one of the most significant
issues in wireless sensor networks (WSNs) [1, 2]. In this paper, we proposed an efficient version of TSEP
Protocol, which prolongs the networks lifetime by efficient utilization of sensor energy, as we have
simulated. We evaluated the performance of our protocol and compared the results with the TSEP. And
from the results of simulation, it can be concluded easily that our proposed efficient routing protocol
performs better in terms of network lifetime and stability period.
KEYWORDS
Wireless sensor network, Stable Election Protocol, Threshold sensitive stable election protocol.
1. INTRODUCTION
Advances in technology have led to the development of wireless network domain. Each sensor
node in WSN is a small sized and low powered electro-mechanical sensing device [3, 4]. These
sensing nodes have many applications like monitoring physical or environmental conditions, such
as temperature monitoring, humidity monitoring, sound monitoring, motion monitoring etc.
Functionality of wireless sensor devices purely depends upon the battery life time which is very
limited in case of wireless sensor. Wireless Sensor Networks allows us to use the collection of
these small sensor nodes for enormous real live applications.
WSN made up of few to thousands of small sensor, which continuously sense the application
environment for the relevant data information and send information to sink node as data
packets.Sensor nodes can be either stationary or mobile depends on the application and can be
deployed in the environment randomly or by using proper deployment mechanisms. Sensor’s
energy gets consumed in continuous sensing the target environment and some of it is reduced
during the transmission and reception of data. It is practically not possible to replace or recharge
sensor node’s batteries once deployed. The objective of our proposed protocol is to prolonged the
network lifetime by utilization of sensor node’s energy, for this purpose an improved version of
TSEP and also Evaluated the Performance of TSEP Protocol in WSN.

International Journal of Advanced Smart Sensor Network Systems (IJASSN), Vol 5, No.3/4,October 2015
18
2. BACKGROUND
2.1 LEACH PROTOCOL (Low Energy Adaptive Clustering Hierarchy):
It is a clustering based routing protocol, proposed in [5] where CH is always elected randomly
and uniformly out of all the nodes in the network, based on some probability. Each node
generates a random number ‘r’ between 0 to 1, if generated random value i.e. ‘r’ is less than
threshold value of that cluster, computed by the formula given below, then this one node will
become the Cluster Head for this round.
ܶ = ቊ
௣
ଵି௣[௥.௠௢ௗଵ/௣]
݂݅ ‫݌‬௡௥௠ ߳ ‫ܩ‬
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(1)
Where, G is set of sensor nodes which have not become CH in 1/P rounds and r is the current
round. LEACH works in iterations, where each iteration or round includes the CH set up followed
by aggregation of data packet and the transmission of that aggregated data packet to the Base
Station (sink). Clusters set up phase will takes place in every round. The network in case of
LEACH is homogeneous and energy constrained. After the formation of cluster, sensor nodes
sense and transmit data to the CH of corresponding cluster.
2.2 SEP(Stable Election Protocol):
A Stable Election Protocol (SEP)[6], is a heterogeneous routing protocol, having the two different
levels of discrimination of nodes using parameters like additional energy factor ‘α’ between the
advance sensor node and the normal sensor nodes and the fraction ‘m’ of advance sensor nodes
which enhance the network stability period which is critical in many real world applications. The
probabilities used by the normal nodes and advance nodes to be chosen as a cluster head will be
computed by using the formulas shown below:
‫݌‬௡௥௠ =
‫݌‬
1 + ݉. ߙ
(2)
‫݌‬௔ௗ௩ =
‫1(݌‬ + ߙ)
1 + ݉. ߙ
(3)
Where, p represents probability of each sensor node to be chosen as Cluster Head.
2.3 TSEP(Threshold Sensitive Stable Election Protocol)[7]:
This protocol comprises of two parts:
• Its a reactive based routing protocol:
– Transmission dissipates more energy than sensing.

18
– Will takes place when it reaches to specified threshold.
• Three different levels of energy discrimination in sensor nodes.
1. Normal Nodes
2. Intermediate Nodes
3. Advance Nodes
Energy for Normal nodes = ‫ܧ‬௢ (4)
Energy for Intermediate nodes= ‫ܧ‬௜௡௧ = ‫ܧ‬௢(1+µ) (5)
Energy for Advance nodes = ‫ܧ‬஺஽௏ = ‫ܧ‬௢(1+α) (6)
The optimal probability of nodes:
‫݌‬௡௥௠ =
௣೚೛೟
ଵା௠.ఈା௕.ஜ
(7)
‫݌‬௜௡௧ =
௣೚೛೟.(ଵାµ)
ଵା௠.ఈା௕.µ
(8)
‫݌‬௔ௗ௩ =
௣೚೛೟.(ଵାఈ)
(9)
For calculation of threshold depending on their probabilities:
ܶ௡௥௠ = ቊ
௣೙ೝ೘
ଵି௣೙ೝ೘[௥.௠௢ௗଵ/௣೙ೝ೘]
݂݅ ‫݌‬௡௥௠ ߳ ‫ܩ‬′
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(10)
ܶ௜௡௧ = ൝
௣í೙೟
ଵି௣೔೙೟൤௥.
೘೚೏భ
೛೔೙೟
൨
݂݅ ‫݌‬௜௡௧ ߳ ‫ܩ‬′′
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(11)
ܶ௔ௗ௩ = ቐ
‫݌‬௔ௗ௩
1 − ‫݌‬௔ௗ௩[‫.ݎ‬ ݉‫݌/1݀݋‬௔ௗ௩]
݂݅ ‫݌‬௔ௗ௩ ߳ ‫ܩ‬′′′
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(12)
Where ‫ܩ‬′
, ‫ܩ‬′′
, ‫ܩ‬′′′
are the set of normal, intermediate and advance nodes respectively. In case of
original TSEP, at the moment of cluster change, the elected CH broadcasts the parameters listed
below-
• Report Time (TR)
• Attributes (A)
• Hard Threshold (HT)
• Soft Threshold (ST)

18
2.3.1 Energy Analysis of TSEP:
Total Energy of Normal Nodes, Intermediate nodes, Advance nodes are:
‫ܧ‬଴(1 − ݉ − ܾ. ݊), ‫ܧ‬଴. ݊. ܾ(1 + ߤ) and ݉. ݊. ‫ܧ‬଴(1 + ߙ).
Total Energy will be ݊. ‫ܧ‬଴(1 + ݉. ߙ + ܾ. µ) (13)
Energy Dissipation:
Energy Dissipation of Cluster is
‫ܧ‬௖௟௨௦௧௘௥ = ‫ܧ‬஼ு + ‫ܧ‬௡௢௡஼ு (14)
Where
Eେୌ = L. Eୣ୪ୣୡ ቀ
୬
୩
− 1ቁ + L.
୉ీఽ୬
୩
+ L. Eୣ୪ୣୡ + L. ϵ୤ୱ. d୲୭୆ୗ
ଶ
(15)
‫ܧ‬௡௢௡஼ு = ‫.ܮ‬ ‫ܧ‬௘௟௘௖ + ‫.ܮ‬ ߳௙௦. ݀௧௢஼ு
ଶ
(16)
Where ߳௙௦ depends on the transmitter amplifier model we use and ݀௧௢஼ு is the distance between
the non-CH node and its CH. Assuming that nodes distribution is purely uniform, it can be shown
as
‫݀[ܧ‬௧௢஼ு
ଶ ] = ∬(‫ݔ‬ଶ
+ ‫ݕ‬ଶ)ߩ(‫,ݔ‬ ‫ݕ݀ݔ݀)ݕ‬ =
ெమ
ଶ.గ.௞
(17)
Where ρ(x, y) is nodes distribution.
3. PROPOSED ALGORITHM
To propose an energy efficient routing algorithm, which can reduces the energy consumption
inside the network, by selecting a sensor node having higher residual energy as CH. It also
includes concept hard threshold and soft threshold to reduce the loss of energy during the
transmission to CH by sensor node, as most of energy of a sensor gets consumed in data
transmission. Energy for Normal nodes = ‫ܧ‬௢
Energy for Intermediate nodes = ‫ܧ‬௜௡௧ = ‫ܧ‬௢(1+µ) (18)
Energy for Advance nodes = ‫ܧ‬஺஽௏ = ‫ܧ‬௢(1+α) (19)
The optimal probability of nodes:
‫݌‬௡௥௠ =
ா೚
(20)

18
‫݌‬௜௡௧ =
ா೚.(ଵାµ)
(21)
‫݌‬௔ௗ௩ =
ா೚.(ଵାఈ)
(22)
Calculation of threshold values depending on the residual energy rather than probabilities:
ܶ௡௥௠ = ቊ
௣೙ೝ೘
ଵି௣೙ೝ೘[௥.௠௢ௗଵ/௣೙ೝ೘]
∗
ோா೙ೝ೘
ாಲೇಸ
݂݅ ‫݌‬௡௥௠ ߳ ‫ܩ‬′
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(23)
ܶ௜௡௧ = ൝
௣í೙೟
ଵି௣೔೙೟൤௥.
೘೚೏భ
೛೔೙೟
൨
∗
ோா೔೙೟
ாಲೇಸ
݂݅ ‫݌‬௜௡௧ ߳ ‫ܩ‬′′
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(24)
ܶ௔ௗ௩ = ቊ
௣ೌ೏ೡ
ଵି௣ೌ೏ೡ[௥.௠௢ௗଵ/௣ೌ೏ೡ]
∗
ோாೌ೏ೡ
ாಲೇಸ
݂݅ ‫݌‬௔ௗ௩ ߳ ‫ܩ‬′′′
0 ‫ݐ݋‬ℎ݁‫݁ݏ݅ݓݎ‬
(25)
Where ܴ‫ܧ‬௡௥௠ , ܴ‫ܧ‬௜௡௧, ܴ‫ܧ‬௔ௗ௩ are the residual energy of normal, intermediate and advance node
respectively and ‫ܧ‬஺௏ீ is the Average Energy of the all the nodes in WSN and ‫݌‬௡௥௠, ‫݌‬௜௡௧ , ‫݌‬௔ௗ௩
are the probabilities of normal ,intermediate and advance node respectively , which depends on
the energy of the node. Where ‫ܩ‬′
, ‫ܩ‬′′
, ‫ܩ‬′′′
are the set of normal nodes, intermediate and advance
nodes respectively. In TSEP, at the time of changing in cluster, the Cluster Head (CH) broad-
casts same parameters as TSEP does. Thus, trying to reduce probabilistic behaviour of the TSEP,
to make it depends on the residual energy.
3.1 CH selection Phase:
In our protocol, we select the CH based on the weighted election probabilities of the nodes, which
basically depends on the residual energy. In our proposed network election probabilities are
different based on the three different levels of heterogeneity in the network. The probabilities of
election of the CH for normal nodes, intermediate nodes and advanced nodes can be calculated as
given in equation (20), (21) and (22). CH selection is done based on the thresholds. Each node
generates a random value between 0 and 1 and if this value is less than its particular threshold
then the node can become the CH. Calculation of thresholds based on the probabilities of the
nodes and can be obtained as shown in equation (23), (24) and (25). And then again we check the
all the member node, if any member node is having more energy than the CH, so the transmission
will be done by that node only i.e. shown in the pseudo code given below
Pseudocode of CH selection:
newCH=CH;
for (c=0, cluster =0: c < clustersize: c++, cluster++ )
{
If ( newCH.Energy < cluster(c).Energy)
newCH=cluster(c)
}

18
Now the transmission will takes place from the newCH. All sensor nodes in WSN keep sensing
the application environment continuously. As parameters out of attribute set reaches to hard
threshold, transmitter will be turned on and data will be transmitted to Cluster Head, however this
is for the first iteration when this condition becomes true or met. This sensed value will be stored
in an internal local sense variable, called its Sensed Value (SV). Then for second time onward,
sensor nodes will transmits the data if sensed value is greater over the hard threshold value (TH)
or if difference of current sensed value and SV variable value is equal to or greater over soft
threshold. So, by considering these both thresholds, number of data transmissions rounds can be
controlled to save or control the energy of sensor node, as transmission will done only when
sensed value reaches hard threshold(HT). While the further transmissions of sensed data packets
are led by soft threshold, as it will reduce transmissions rounds when there is a very small
changes in values, even smaller than interests. Some of significant features along with the
features of TSEP are described below:
1) Selection of Node to become CH purely depend upon the Residual Energy of sensor node
using the equation (23), (24) and (25).
2) Strictly focusing on the higher residual energy node by checking all the neighbour nodes in the
cluster, which have the greater residual energy.
3) Nodes sense the environment continuously but transmission is not done frequently.
4) The users can change the attributes as per requirements, as attributes set always broadcasted at
the time of cluster change.
5) Still it is a probabilistic algorithm, but works specifically based on the Energy of nodes and
finally selects the nodes based on the residual energy rather than probabilities.
6) Still the only main adjustments of this protocol is that, if threshold value is not reached, user
will not be able to get any information, even if one or all the sensor nodes dies, system will never
came to know about that. In nutshell, this approach is useless for the applications where a data is
required continuously.
4. SIMULATION RESULTS
we have used the MATLAB simulation tool to evaluate the performance of TSEP and also of the
proposed protocol. The performance of our proposed protocol is compared with TSEP based on
energy dissipation and longevity of wireless network. Our demonstrated network field have 100
sensor nodes deployed randomly in a region of 100×100 area (in meters). With the value of m =
0.1, α = 1 for the various locations of BS in simulated environment. For the first and all iteration
or round of simulation, we have considered the BS at the centre of the network area that is (50,
50) i.e. sink is static. This has to be done to observe change in stability of network and network’s
life about at various BS positions or locations.
The used parameters in simulations are listed below in Table 1
Parameters Value
Eୣ୪ୣୡ 60nJ/bit
Eୈ୅ 4nJ/bit/message
߳௙௦ 8pJ/bit/m4
߳௠௣ 0.0013pJ/bit/m4
‫ܧ‬௢ 0.6J

18
Message size 5000bits
Figure(1): Nodes Distribution.
Figure(2): Dead Nodes Representation.
0 10 20 30 40 50 60 70 80 90 100
0
10
20
30
40
50
60
70
80
90
100
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
0
10
20
30
40
50
60
70
80
90
100
# of rounds
Deadnodes
Nodes dead during rounds
TSEP and Modified TSEP

18
Figure(3): Alive Node Representation.
Figure (1) represents the pure random deployment of the Sensor nodes in the Wireless sensor
Network. Figure (2) represents the number of Dead node with respect to the number of rounds, as
well as figure (3) represents the number of Alive node with respect to the number of rounds.
Where yellow marked line shows the better performance of the Extended TSEP and the blue
marked line shows the performance of TSEP.
By demonstrating simulations in MATLAB Tool, it has been observed that:
• Extended TSEP has enhanced stability period than TSEP protocols, as shown in Figure (2) and
Figure (3).
• The network life for Extended TSEP was increased as compared to others.
• Increased and decreased in number of alive and dead nodes with respect to the time
respectively.
5. CONCLUSION
We dedicated out work to the cause of finding better solutions for the known problems in the
threshold sensitive routing protocols in WSNs. In the course of our study we dissected the
problems and investigated their genesis based on which we proposed a novel technique for
tackling the problem of maximizing the network lifetime of a sensor network. The proposed
algorithm is a threshold sensitive routing protocol which elects the node with highest residual
energy as the CH, for this we introduced an additional parameter in the CH election procedure of
TSEP.
The results of the simulations substantiate our claims on the efficiency of our proposed algorithm
when gauged in terms of the residual energy of the nodes in the sensor network and stability
period of the network. Our algorithm is seen to outperform its contemporary algorithms namely
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
0
10
20
30
40
50
60
70
80
90
100
# of rounds
Alivenodes
Nodes alive during rounds
TSEP and Modified TSEP

18
TSEP , which can be attributed to the changes that were suggested by us , hence we can
undoubtedly conclude that our proposed algorithm can cater to a wider range of real time
applications and is successful in achieving the objectives of our study.
REFERENCES
[1] I.F. Akyildiz, W. Su, Y. Sankarasubramaniam, and E. Cayirci, "A Survey on Sensor Network", IEEE
Communication Magazine, 2004, pp. 102-114.
[2] Mittal, R.Bhatia, M.P.S., “Wireless sensor networks for monitoring the environmental activities”,
IEEE International Conference on Computational Intelligence and Computing Research(ICCIC),
2010, pp.1-5.
[3] Young, D.J., “Interface electronics for MEMS-based wireless sensing applications”, International
Symposium on VLSI Design Automation and Test, 2010, pp. 130-133.
[4] Warneke, B.A., Pister, K.S.J., “MEMS for distributed wireless sensor networks”, 9th International
Conference on Electronics, Circuits and Systems 2002, pp. 291- 294 vol.1.
[5] W. B. Heinzelman, A. P. Chandrakasan,H.Balakrishnan, "An Application-SpecificProtocol
Architecture for Wireless Microsensor Networks",IEEE Trans.Wireless Commun., vol. 1, no. 4, 2002,
pp.660-770.
[6] G. Smaragdakis, I. Matta and A. Bestavros, "SEP: A stable election protocol for clustered
heterogeneous wireless sensor networks", in Second International Workshop on Sensor and Actor
Network Protocols and Applications (SANPA 2004).
[7] A Kashaf, N.Javaid, Z.A.Khan,I.A.Khan,”TSEP:Threshold-sensitive stable Election Protocol for
WSNs”,10th International Conference on Frontiers of Information Technology 2012.
[8] R.K.Yadav,Arpan Jain on,” CHATSEP: Critical Heterogeneous Adaptive Threshold Sensitive
Election Protocol for Wireless Sensor Networks”,in IEEE Conference on Wireless and Networking
2014.
[9] Yogesh Mishra, Ashish Singhadia, Rashmi Pandey,” Energy Level Based Stable Election Protocol in
Wireless Sensor Network”,in International Journal of Engineering Trends and Technology (IJETT) –
Volume 17 Number 1 – Nov 2014.

THRESHOLD SENSITIVE HETEROGENOUS ROUTING PROTOCOL FOR BETTER ENERGY UTILIZATION IN WSN

More Related Content

What's hot (15)

Viewers also liked (14)

Similar to THRESHOLD SENSITIVE HETEROGENOUS ROUTING PROTOCOL FOR BETTER ENERGY UTILIZATION IN WSN (20)

Recently uploaded (20)

THRESHOLD SENSITIVE HETEROGENOUS ROUTING PROTOCOL FOR BETTER ENERGY UTILIZATION IN WSN