Energy Efficient Hierarchical Clustering Approaches in Wireless Sensor Networks: A Survey

Table 1

Summary of cluster-based protocols.

Cluster-based hierarchical energy efficient protocols
Protocol	CH selection; approach	Type	Advantages	Disadvantages
LEACH [15]	Probabilistic	Distributed	(i) Nodes equally share load up to some extent; (ii) TDMA avoids unnecessary collisions; (iii) Allocated time slots avoid excessive energy consumption	(i) Single-hop intercluster communication; (ii) Energy holes and coverage problems; (iii) CH selection is probabilistic without considering energy; (iv) Extra overheads due to dynamic clustering
LEACH-C [16]	Probabilistic	Centralized	(i) Global view of the entire network; (ii) Even distribution of load; (iii) Energy efficient routes	(i) Network overhead; (ii) CH selection is probabilistic; (iii) Reselection process is resource expensive
CCWM [17]	Nonprobabilistic	Distributed	(i) Improves routing and network lifetime; (ii) Suitable for static and small scale networks	(i) Nonoptimized CH election; (ii) Increases network overhead; (iii) Not suitable for large scale networks
-means; clustering [18]	Probabilistic/centroid-based	Distributed	(i) Simplified approach; (ii) Improved network lifetime	(i) Periodic reformation of clusters; (ii) Inefficient distribution of load; (iii) Reselection is based on centroid distance
CHEF [19]	Probabilistic/nonprobabilistic	Distributed	(i) Keeping in view the entire network for CH election; (ii) Optimal CH selection	(i) Excessive message and communicational overhead; (ii) Expensive CH election process in terms of energy consumption
UCS [20]	Nonprobabilistic/probabilistic	Distributed	(i) Balanced energy consumption; (ii) Suitable for homogeneous networks	(i) Due to random deployment, the number of nodes may vary a great deal; (ii) The optimal number of CH is due to multilayer approach
NUDND [21]	Nonprobabilistic	Distributed	(i) Achieved load balancing; (ii) Resolved energy hole problem; (iii) Works well in predefined nodes position	(i) Not suitable for random deployment; (ii) Not suitable for mobile node and large scale networks
EADC [22]	Nonprobabilistic	Distributed	(i) Achieves load balancing among CHs; (ii) Addresses imbalance energy consumption	(i) Redundant messages cause additional energy consumption; (ii) Uneven clustering in random deployment
LEACH-MAC [23]	Probabilistic	Distributed	(i) Addresses randomness in CH count; (ii) Nodes equally sharing load up to some extent; (iii) Achieves energy efficiency	(i) The CH selection being based on random value.; (ii) Single-hop intercluster communication; (iii) CH selection being probabilistic without considering energy
EADUC [24]	Nonprobabilistic	Distributed	(i) Solves energy hole problem; (ii) Maximizes network lifetime; (iii) Has unequal clustering strategy	(i) Redundant sensed and transmission messages; (ii) Extra energy consumption affecting network performance