Table 1.

Improved: Related work.

Reference	Advantages	Remarks
LEACH 2002 [4] is used as an example.	Among the earliest protocols for data transfer in a WSN it is simple. Because of threshold-based stochastic cluster head selection, there is a bottleneck in the area surrounding BS. In the case of a heterogeneous network, this rule does not apply.	The solution was to create heterogeneity among nodes by assigning them increasingly difficult tasks to complete.
Seema Bandhopadhyay and colleagues 2003 [5]	It was suggested that raising the degrees of hierarchy would result in greater energy savings. Communication is only possible via hierarchies in lag.	When selecting a CH, it is necessary to take into account the residual energy of the node.
Liang Ying and colleagues [6] published their findings in 2005.	LEACH's stochastic cluster head selection has been optimized.	When selecting a CH, it is necessary to take into account the residual energy of the node.