- Clustering algorithms aim to organize wireless sensor nodes into clusters to optimize energy efficiency and enable scalability. Clustering involves selecting certain sensor nodes as cluster heads that aggregate data from member nodes and transmit to the base station. - The document discusses several clustering objectives like load balancing, fault tolerance, reducing energy consumption and latency. It also introduces some popular clustering routing protocols like LEACH, PEGASIS and TEEN. - LEACH is one of the most widely used clustering algorithms that selects cluster heads randomly and rotates this role to balance energy usage among nodes and prolong network lifetime. It forms clusters based on received signal strength.

1. ENERGY EFFICIENT
CLUSTERING ALGORITHMS
FOR WIRELESS SENSOR NODES
Shivang Rana

2. INTRODUCTION TO CLUSTERING
• Clusters: Disjoint Sensor nodes in non-overlapping subsets.
• Clustering: Using Clusters, to perform energy optimization &
support scalability.
• Determines the set of nodes that provide backbone to connect
network to base stationHierarchical Model
Member Nodes: Data sensing transmitting to
Cluster Head Cluster Head: Data Aggregation
transmitting to Base StationM
C
M
M
M
M
M M
Cluster Head can use single hop to relay data to other
heads
Need of Re-Clustering : Load Balancing
Position of Cluster-Head: key to Energy Efficient
Multi-hopping Routing: Inner Cluster-Head

3. CLUSTERING OBJECTIVES:
• Load Balancing:
-Equal sized Clusters
-No Cluster head gets exhausted faster.
-Identical no. of Sensor Node in each Cluster
• Fault Tolerance: if Cluster head is damaged
-Re-Clustering
-Using Backup-Cluster head (Assigned)
-Using Rotation Strategy
• Lesser Energy Consumption:
-Data Aggregation
-Inner- Cluster & Intra-Cluster Communication : lessens longer
transmission losses
-Cluster Head: Only Data communication
• Path minimization Energy
Optimization
AIM

4. CLUSTERING OBJECTIVES:
• Improved Connectivity & Lesser Delay:
-Directly connecting each Cluster Head with Base Station can lead to
limited & restricted length of communication.
-Inter cluster head communication or Long range communication
abilities.
• Latency Reduction:
-Data collisions avoiding: Only Cluster Head perform data transmission
-Data broadcast: Flooding in Flat routing Scheme: Hop by Hop
• Least Cluster Count:
-Cluster Head: Resource-rich
-Try to minimize: Cause CH more susceptible & precious than other
SNs.
• Maximize the Network Lifetime: Increasing Life-Span of
Cluster

5. CLUSTERING OBJECTIVES:
• Data Aggregation: ( Clustering head)
-To eradicate the redundant communication & provide the merged data
to BS
-CHs shaped as tree structure to broadcast aggregated data by multi-
hopping
• More Robustness:
-More handier to control network topology changes: Cause it happens
in one cluster only & the whole full network remains strong only
• Energy Hole Avoidance:
-Each node msg: Self generated & relayed traffic
-Sensor nodes closer to BS, are needed to broadcast more traffic
towards BS
-This creates an energy hole around BS, cause nearby nodes exhaust
energy faster
• Collision Avoidance:
-Two modes known Intra-Cluster & Inter-Cluster.

6. CLUSTER BASED ROUTING PROTOCOLS
• Hierarchical Routing Protocol :
-Minimize energy utilization during data gathering &
disseminating.
-Node : Great processing power  Cluster Head
-CH : totals the data sent by powered sensor nodes

7. LEACH (Low Energy Adaptive Clustering Hierarchy)
PEGASIS (Power-efficient gathering sensor information system)
TEEN (Threshold Sensitive Energy Efficient Sensor Network Scheme)
APTEEN (Adaptive Periodic Threshold-Sensitive Energy Efficient)
EEHC
HEED (Hybrid, Energy-Efficient & Distributed)
UCS (Unequal Clustering Size)
FBR (Flow Balanced Routing)
EECS (Energy Efficient Clustering Scheme)
PEACH (Power Efficient & Adaptive Clustering Hierarchy)
TTCRP (Two Tier Cluster Based Routing Protocol)
DAIC (Distance Aware Intelligent Clustering)

8. LEACH (Low Energy Adaptive Clustering
Hierarchy)
• Known & Elegant Clustering Algorithm : by selecting CHs in
rounds
• Rotation of Group Heads among the Cluster
• Balanced Energy Utilization  Extended Lifetime
• Each Round has two stages:
-Set Up Stage : Election of CH
-Steady Stage : Work done by elected CH
• Structure Nodes based on : Signal Quality
-Local Cluster Heads : Routers to the SINK

9. LEACH (Low Energy Adaptive Clustering
Hierarchy)

10. • Steady State:
• To minimize Overhead: Time-Frame
Steady State > Setup State
• LEACH: Self Organization Technique  Optimizes WSN
communication
• Mobility is supported
• A choice of Favourable cluster heads at the current round
Unfavourable cluster-heads determination in the later
round.
•Sensing
•Transmitting
data
Node
•Data Aggregation
•Sending Data
Cluster-Head
•Acquiring Data
•Indicate or even
take control
steps
Base Station
ISSUE

11. • Better Solution : Updating Threshold Value
By incorporating a factor that raises the threshold for any node
that has not been a cluster head for a certain number of rounds.
• Thus, possibility of this node turning into a cluster head
expands due to the higher threshold.

12. PEGASIS (Power Efficient Gathering in Sensor
Information System)
• Improvement over LEACH
• Chain based protocol:
• Chain of nodes: shape a way to BS.
• Diminishes the power required to transmit Info/round
consistently.
• Assumptions:
1. Every sensor node can directly talk to BS.
2. All nodes keep up a complete database about the location of every
other node in system.
3. All sensor nodes have same level of energy & are likely to die at same
time.
Node
Nearest
Neighbours
Signal Quality
Base Station
Alternate Speaking

13. TEEN PROTOCOL
• Hierarchical Clustering
• Responsive system
• Cluster Formation & Data Transfer: LEACH
• Added Traits :
A. Hard Threshold (HT)
B. Soft Threshold (ST)
Extreme
&
Sudden
changes
environ
ment
(TEEN)
Node
Node
Node
Node
Utilization of ST & HT
Decrease the no. of
Transmissions
Diminishes Energy
Dissipation
Suited for time critical
data sensing
applications

14. Sensed value
> Hard
Threshold
Present Value – SV
> Soft Threshold
SV: Inner Variable
(Sensed Value)
NodeSwitch on
Transmitt
er
Ready
data
Send
Data

15. THANK YOU
!!!