special issue comparison of cluster based routing...

Comparison of Cluster Based Routing Protocols in

Wireless Sensor Network: A Recent Survey

Murugaanandam.S

1, Karthika Sundaran

2 and Ganapathy.v

3

Department of Information Technology, SRM University, Chennai

[email protected], [email protected],

[email protected]

Abstract

The applications of Wireless Sensor Networks (WSNs) have

grown tremendously over the past few years. The cluster

mechanism extends the life of a network and supplies

additional economical functioning procedures in WSNs. A

method to subdivide the field into groups of sensors is defined

as clustering. A Cluster Head (CH) is elected either by the Base

Station (BS) or by the specific protocol within a cluster.

Optimized clusters can save certain amount of energy in the

WSN. Based on the parameters like cluster count, cluster size,

cluster density, message count, node selection, heterogeneity of

nodes, location awareness and CH selection methods, we have

surveyed and compared ten varied consistent cluster protocols

for WSNs. The comparison highlights the advantages and

disadvantages of these protocols. Routing method, clustering

method, algorithm complexity, node deployment, scalability,

location awareness, load balancing, network life time and

energy efficiency have been considered as a few important

characteristics for comparing the protocols. Factors such as

network types, mobility and topology of various protocols are

also surveyed in this paper. Based on the survey of the network

protocols, we propose a brief outline of a new clustering

algorithm, which will be more efficient than the existing ones.

Keywords: Cluster count, cluster size, cluster density,

lifetime

1. INTRODUCTION A system of nodes connected to one or more sensors is the basic

layout of a wireless sensor network. The network nodes in such

International Journal of Pure and Applied MathematicsVolume 114 No. 7 2017, 559-571ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu

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devices have various components: a microcontroller, an electronic

circuit to interface with the sensors, a radio transceiver attached to an

exterior antenna and finally a battery to supply energy to the system of

nodes. To convey the physical or environmental conditions such as

temperature, sound, pressure etc., a wireless network of spatially

distributed sensors are deployed.

Dimension of a node may vary from a smaller to a larger size.

Depending on the quality of the individual sensor nodes the price of

sensor nodes may vary. Therefore, size and cost of the node are

related to the constraints on resources like memory, processing speed

and measure of communication information and energy.

The topology of WSNs may either be complicated or simple. The

propagation technique between the hops of the network may be

routing or flooding. Fig. 1.1 gives the schematic diagram of

components of a sensor node within the WSN. In all WSNs sensing,

processing, position finding, mobilizing and locating Base Station

(BS) are the various functionalities.

Fig. 1.1 Components of a sensor node in WSN [1]

The WSN can be applied in the field of trespasses detection in

forest spaces, paddy field environmental management, process

observation management in the industry, machine condition

observations, many military applications etc. In this paper ten different

clustering protocols based on numerous factors such as the various

clustering properties, the network type, mobility, WSN characteristics

and topologies are compared. Based on these comparisons, we

propose the best clustering algorithm which will be more energy

efficient and hence have a prolonged network life time.

1.1 Features and General characteristics of Wireless Sensor Networks

Wireless sensor networks customize the routing power

management, knowledge dissemination and protocol management.

Depending on the number of applications and their respective

specifications, the focus is given to the routing protocols [1].

International Journal of Pure and Applied Mathematics Special Issue

560

Nodes have constraints on the consumption of power because of

poor quality batteries or more energy utilization for specific

applications. They have to deal with the failure of nodes and also have

to be mobile. Nodes are scattered around and are scalable. These

nodes should be capable of withstanding any environmental changes.

The nodes are easy to use and are mostly employed in Cross-

layer style. Node deployment is easy because of smaller node size.

1.1.1 Kinds of Sensors employed in WSN

The various sensors employed in WSNs are thermal, magnetic,

visual, infrared, acoustics and microwave radar. Sensors capable of

measuring temperature, humidity, noise level, vehicular movements,

presence and absence of ups and downs of objects, mechanical stress

levels, speed and direction are also employed.

1.1.2 Communication problems in WSN Communication in WSNs requires prescribed bandwidth and

sharing among all nodes within the WSN. Spatial application and

information measure used in the native state are the required

constraints. The sensing, processing and transmission are done by the

sensor nodes which consume a large amount of energy. In order to

make the communication efficient in WSN, energy efficient protocols

have to be used.

2. ROUTING PROTOCOL CLASSIFICATION

Routing protocols provide the measures needed for

communication between the sensor nodes and BS. Different routing

protocols used in WSN are enhanced by various routing techniques

.

3. CLUSTERING PROTOCOLS FOR WSN The clustering protocols can be categorized based on the process

of selecting the CH. The algorithms are classified as probabilistic or

non-probabilistic.

3.1 LEACH [Low Energy Adaptive Clustering

Hierarchy] LEACH is a simple and efficient routing protocol used for creating

clusters. As shown in Fig. 1.2, LEACH uses time division

multiplexing (TDMA) for assigning slots for individual nodes to avoid

network traffic, minimal power consumption and to improve

substantial lifetime of the cluster. Generally LEACH protocol is used

to increase the life time of the network and decrease the energy usage.


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There are two phases in each round of LEACH protocol called set-up

phase and steady state phase .

Each cluster has many sensor nodes, the protocol elects a node

called as CH and the remaining available nodes are called member

nodes. Each of the member nodes collects data from the dependent

region and sends this information directly to the CH. The CH receives

the copy of redundant information. The received redundant

information is aggregated then compressed by the CH and is sent

directly to the BS. A stochastic algorithm helps LEACH protocol to

decide which sensor node is to be elected as CH in each round.

LEACH protocol believes that the energy consumption of each and

every node close to the BS is very low and the node with the longest

distance from the BS is very high. But nodes which are always on

active condition would waste more energy unnecessarily. To reduce

the interference between clusters, LEACH protocol uses CDMA based

method for communication.

Fig. 1.2-Round and phases of a clustering protocol [11]

3.2 LEACH –T [Threshold Based Low Energy Adaptive Clustering Hierarchy]

T-LEACH is a threshold based CH replacement method in WSN.

It is a hierarchical routing protocol. In T-LEACH, the CHs are

selected randomly. It is an intra-cluster protocol which supports

homogeneous network. The cluster size is dynamic and cluster density

and the cluster coverage are limited. T-LEACH does not provide

information on the nodes locations. Cluster scalability and energy

efficiency are low when compared to other protocols.

CH selection is done by T-LEACH using a threshold value of its

residual energy to minimize the number of CH selections. The

network lifetime is increased and the replacement cost is reduced

because of the number of reductions in the CH selections. Compared

with the other clustering protocols, T-LEACH is found to be an

efficient protocol .

3.3 LEACH-C [Centralized Low Energy Adaptive Cluster Hierarchy]

Centralized approach is used for CH selection and LEACH-C also

utilizes the steady state protocol as in LEACH. Similar to LEACH,

LEACH-C also uses two phases. In the setup phase, location

information and energy level information of each node are received by

the BS. Clusters are configured by the BS and it identifies the CHs


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within the cluster by the scheduled manner [13]. CH selection and

cluster formation are decided by the BS. CHs are selected randomly

and number of CHs is limited. BS selects CHs based on the nodes

energy levels. Large scale network cannot use LEACH-C protocol

since far-distant nodes find it difficult to send their status information

to the BS. LEACH-C protocol increases the latency and delay because

the CH role changes frequently. Frequent exchange of messages is not

feasible to transfer information between cluster nodes in LEACH-C.

3.4 HEED [Hybrid Energy Economical Distributed] Different CH selections based on the amount of its residual energy

is done by HEED protocol [32, 33]. The primary objectives of HEED

are to extend the survival period of network by distributing power

utilization, restricting the clustering process within the number of

iterations or rounds, avoiding or minimizing the communication and

routing problems, and constructing optimized clusters with powerful

CHs without any special node capability like location awareness.

There are two basic limitations to select CHs.

The first limitation is the restricted power level of individual

sensor nodes. The second limitation is, if the node densities are high

within a cluster the communication between the nodes will be

reduced. HEED is not capable of fixing the cluster count in each round

and it does not have the aware of heterogeneity. Node distribution is

not based on assumptions, even though the nodes are not

synchronized, communication continues. Created clusters are well

distributed and termination process is in constant/fixed time. HEED

requires communication only within the clusters. Using HEED we can

decrease the utilization of energy by decreasing the communication

load, thereby increasing the survival period of the network. Due to the

random selection of CH, higher communication overhead is caused.

Communication established between a CH and its member nodes,

between different CHs and between a CH and a BS, causes various

CH communication issues such as limited resource and bandwidth

usage, sensor energy constraints, less feasibility to rechargeable and

replacement nodes in clusters. To obviate some of the communication

limitations, energy-conserving protocols may be used.

3.5 EECS [Energy Efficient Cluster Scheme] Energy Efficient Cluster Scheme (EECS) is a periodical

knowledge gathering applications in WSNs. The periodic data

collection process within the WSN is done by a new protocol called

Energy Efficient Clustering Scheme (EECS). In this protocol there are

two phases used to form a cluster. In the first phase called CH

election, CHs are selected among the multiple nominee nodes. This

nomination results in choosing better quality energy back-up CHs.


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This type of selection process differs from other protocols like

LEACH and HEED.

In the second phase, the member nodes are included within the

cluster by choosing its communication metrics while communication

is established between the CHs as well as BS. EECS protocols are

mostly self-manageable, energy efficient and extend the survival

period of the network when compared to all other clustering protocols.

BS sends a simple, ‘keep alive kind of hello message’ to its cluster

nodes to ensure the connectivity between them in the network

deployment phase. The distances between the nodes and the BS are

calculated based on the received signal strengths which ensure the

power level utilization when communication happens. In the cluster

creation phase the loads among the CHs are balanced by the respective

distances between the nodes and the BS. There is a slight control

overhead while selecting the well distributed CH. To balance the load

in the cluster, a novel method namely TEEN is introduced.

3.6 TEEN [Threshold sensitive Energy Efficient sensor Network]

Threshold sensitive Energy Efficient sensor Network is the first

protocol created for a reactive network [16]. This protocol is mainly

used in networks where the sensors respond to sudden changes in their

sensing area. In TEEN protocol, every time a cluster changes, the CH

sends a message to all its member nodes. This message contains

information regarding the attributes of the network and also carries

information about the Hard Threshold and the Soft Threshold values

of the parameters being sensed.

In the Soft Threshold function, a minute difference noted in the

threshold value would activate the sensors and they transmit this

difference value to the CH. This information is saved as a variable

named the Sensed Value (SV). On the other hand, in the Hard

Threshold function, when the value of the sensed parameter exceeds

its threshold value, the sensor nodes become active and start

transmitting the data to their CH.

The transmission of data occurs again only when the next SV

exceeds the Hard Threshold value or when it differs from the value

saved in the variable SV. For every data transmission made by the

sensors, the SV is considered as the current value. Therefore the

number of transmissions made by a sensor is less in the Soft

Threshold function when compared to that of the Hard Threshold.


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Fig. 1.3 Clustering Topology in TEEN

Fig. 1.3 depicts the clustering topology in TEEN protocol. Nodes

are grouped into clusters with a CH which is responsible for routing

information from the cluster to the other CHs or BS. Data travels from

a lower cluster level to a higher cluster level. As it hops from one level

to another, it covers larger distances. This moves the data faster to the

BS. Clustering provides inherent optimization capabilities at the CH.

3.7 APTEEN [Adaptive Periodic Threshold-sensitive Energy Efficient sensor Network]

It is a protocol which has the characteristics of both proactive and

reactive networks. Every time when clusters are formed, CHs are

selected and these CHs initially send a keep alive message to the BS

which contain information such as the value of the sensing parameter,

the Hard and Soft Threshold values, the type of scheduling scheme

used to allot slots for every nodes and the information regarding the

maximum time taken between the two consecutive transmissions from

a node to the BS [14].

APTEEN is a protocol which provides a complete but precise data

recovery. The sensors deployed in such a network not only react to

time-critical situations, but also give an overall picture of the network

at periodic intervals. Thus the historic, current and information for

prediction can be demanded from the network in the form of

historical, on-time and persistent queries respectively. A TDMA

schedule assigns a transmission slot to each cluster and is shown in

Fig. 1.4.

Fig. 1.4 Time Line for APTEEN [14]

3.8 PEGASIS [Power-Efficient GAthering in Sensor Information Systems]

The aim of the protocol is to make the communication successful

to the nearest neighbour nodes by the CH to the BS. This process

enables the sensor nodes to equally distribute their energy within the

cluster network. The selection of first CH from the region is by a

random process i.e. the ith

node available in the region is selected. At


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first the selection process to make a ‘chain like link ’ as shown in Fig.

1.5 is formed by the sensor nodes themselves with the help of greedy

algorithm. Otherwise the BS directly computes this chain link and

broadcasts it to all the nodes available in the network. For constructing

the chain links all available nodes should have complete knowledge of

the network and have the capability of utilizing greedy algorithm [6].

Fig. 1.5 – Data flow Chain to BS.

3.9 CCS [Concentric Clustering Scheme] The Concentric Clustering Scheme (CCS) is a protocol proposed

to avoid the loopholes in PEGASIS. In this protocol, importance is

given to the BS location in order to improve its performance and

stretch the life time of the network. In CCS, a large network is split

into concentric circular tracks which represent multiple clusters. The

first track which is the closest to the BS node is called level 1. The

level numbers are increased based on the distance between the BS and

the tracks accordingly. Each level maintains the node positions,

similar to the chains created by PEGASIS in these tracks. One of the

nodes becomes CH within the chain at each level.

PEGASIS protocol is responsible for communication or data

transmission in CCS. After the CH selection, the lower and upper

level layers would receive the data from the CH that is available

within the same level in a single round. Using the chain, initially, the

available nodes in each level transmit the data themselves to the

nearest nodes in the process of data transmission. After receiving the

data, node fuses with its own data and forwards the data to the next

node. Because of this action, CH node receives a minimum of two

data, after which, CH of each level sends data to the next level CHs.

Finally the level 1 CH submits the data to the BS. The data

transmission process is shown in Fig. 1.6.

In CCS, if the space between the BS and CH is very small when

relates to distances used by all other protocols, the data transfer is

efficient and energy utilization is very small. The concentric circles

split the network into more segments or tracks and the data flow in the

reverse direction is also reduced. The CCS also has its own

drawbacks. The allocation of nodes in each level is uneven and

therefore the levels which contain less number of nodes will soon

exhaust their energy. The residual energy is not considered during the

selection process of CH as it may lead to uneven energy utilization


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among all nodes. PEGASIS and CCS protocols use chains for their

communication with the neighbour nodes using their least

broadcasting power. The long chains use high broadcasting power.

The subsequent CH selection is based on the nearest node presented

within the area rather than their available energy. So they exhaust their

energy quickly and created energy hole within the region of interest.

Fig. 1.6 Data Transmission

Scheme in CCS

3.10 MOCA [Multi-hopping Overlapping Clustering Algorithm]

Data transmission between existing groups is enhanced by this

algorithm known as Multi-hopping Overlapping Clustering Algorithm

(MOC). This MOC algorithm is completely different from the

available ones in which clusters are allowed to overlap. A node

existing in middle between two clusters may perform as a relay node

for CH data transmission as depicted in Fig. 1.7.

Fig. 1.7 MOCA- Overlapping Cluster [16]

MOCA protocol uses the hierarchical routing method and its

network type is homogeneous. The cluster formation is self -managed.

The nodes in this protocol are deployed randomly and do not provide

information regarding its location. Though the network life time is

high, scalability and energy efficiency achieved using this protocol are

very low. The cluster count is variable whereas the cluster size and

density are limited.

Table 1 gives the details of the various parameters used in WSNs.

Based on these parameters different protocols have been classified and

their merits and demerits highlighted. WSN characteristics are routing

method, clustering method, algorithm complexity, node deployment,

scalability, location awareness, load balancing, network life time and

energy efficiency and are listed in Table 1. The network types

depending on the various protocols are mentioned, i.e., whether the


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protocol is homogeneous or heterogeneous. The protocols are

differentiated depending on the mobility of the member nodes, CHs

and BS. Various clustering properties have been reviewed such as

cluster count, cluster size, cluster density, message count, cluster

stability, range of nodes, cluster overlap, connectivity of CH to BS

and the type of data delivered and are given in Table 1. The topology

of every protocol is different depending on the parameters such as

energy, connectivity, threshold value, pre-set value etc. Roles of CH

and CH rotation are the two important characteristics of the CH in

every protocol. The protocols listed in this paper have been classified

based on the above mentioned parameters.

Table 1.0. Comparison of Clustering Limitations & Properties

Based Routing Protocols in Wireless Sensor Network.

4. FUTURE WORK Based on the above study, a consolidated report has been prepared

and given in Table 1. All parameters pertaining to the protocols have

been listed. This Table will be a useful tool to select an appropriate

protocol for a specific application. From the study, we propose to

develop a protocol combining the important favourable features of the

various protocols given in the Table 1. We intend to consider LEACH

protocol as the base for our future research. Thorough analyses of the

proposed protocol are highlighted and brought out the important

advantages over the existing protocols. Mainly extending the life time,

improving the efficiency, minimizing the energy consumption and

optimizing the data transmission will be considered in our further

research. Our Research proposal is suitable for Agricultural,

Environmental and Military based Applications.

5. CONCLUSION


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From the detailed study of the various hierarchical routing protocols

based on their energy and functionality, we conclude that before any

protocol is implemented in WSNs, it is necessary to consider the

power utilization of each node [1]. In this paper, we have surveyed

and compared the various protocols used in WSNs. Based on this

comparison, the best protocol to use with respect to the clustering

methodologies, node deployment, energy efficiency, algorithm

complexity, network lifetime, mobility, various clustering properties

and characteristics can be determined. Though, these routing protocols

show continuous developments over time, still there is a possibility for

further enhancements in WSNs.

6. REFERENCES [1] Jamal N. Al-Karakil- ICUBE initiative of Iowa State University ,

Ames, 2003- Ahmed E. Kama Routing Techniques in Wireless Sensor Networks: A Survey

[2] Ashok Kumar and Narottam Chand, 2011. Location Based Clustering in Wireless Sensor Network, World Academy of Science, Engineering and Technology.

[3] L. Qing, Q. Zhu, M. Wang, 2006. Design of a distributed energy-efficient clustering algorithm for heterogeneous wireless sensor networks, In ELSEVIER, Computer Communications.

[4] Jinchul Choi and Chaewoo Lee, 2011. Energy consumption and lifetime analysis in clustered multi-hop wireless sensor networks using the probabilistic cluster-head selection method, EURASIP Journal on Wireless Communications and Networking.

[5] Changmin Duan, 2007. A Distributed Energy Balance Clustering Protocol for Heterogeneous Wireless Sensor Networks, IEEE WiCon.

[6] Mehrani, M., 2010. FEED: Fault tolerant, energy efficient, distributed Clustering for WSN, IEEE, and Advanced Communication Technology (ICACT).

[7] Farruh Ishmanov and Sung Won Kim, 2009. Distributed Clustering Algorithm with Load Balancing in Wireless Sensor Network, EEE World Congress on Computer Science and Information Engineering.

[8] Mehdi Saeid manesh and Montalba Haji Mohammad, 2009. Energy and Distance Based Clustering: An Energy Efficient Clustering Method for Wireless Sensor Networks, World Academy of Science, Engineering and Technology.

[9] Yan Zhang, Laurence T. Yang & Jiming Chen, 2010, RFID and Sensor Networks, auerbach publication, International Standard Book Number: 978-1-4200-7777-3

[10] Sanjeev Kumar Gupta, Neeraj Jain and Poonam Sinha, 2012.


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Node Degree Based Clustering for WSN, International Journal of Computer Applications (IJCA).

[11] Jiman Hong & Joongjin Kook & SangjunLee & Dungeon Kwon & SanghoYiT- Springer Science + Business Media, LLC 2008LEACH: The method of threshold-based CH replacement for wireless sensor networks.

[12] W. B. Heinemann, A. P. Chandrakasan, and H.Balakrishnan, “An Application Specific Protocol Architecture for Wireless Micro sensor Networks,” IEEE Trans. Wireless Commun., vol. 1,no. 4, Oct. 2002, pp. 660–70. Bergli, V.(2003). Smart RF CC2420: 2.4 GHzIEEE802.15.4/Zigbee RF Transceiver. Retrieved GHz IEEE802.15.4/ Zigbee RF Transceiver. Retrieved from http://focus.ti.com/docs/prod/folders/print/cc2420.html.

[13] Sivad. Muruganathan, Danielc.f. ma, rollyi. Bhasin, and abrahamo. Fapojuwo, University of calgary- IEEE Radio Communications • March 2005. “A Centralized Energy-Efficient Routing Protocol for Wireless Sensor Networks”

[14] Arati Manjeshwar and Dharma P. Agrawal Proceedings “APTEEN: A Hybrid Protocol for Efficient Routing and Comprehensive Information Retrieval in Wireless Sensor Networks” International Parallel and Distributed Processing Symposium 2002 IEEE.

[15] Vijay Kr. Chaurasiya and S. Rahul Kumar, 2008.Traffic Based Clustering in Wireless Sensor Network, IEEE WCSN.

[16] B. Baranidharan and B.Shanthi- December 2011 “A New Graph Theory based Routing Protocol for Wireless Sensor Networks “International journal on applications of graph theory in wireless ad hoc networks and sensor networks”.


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