SMAC-Based WSN Protocol-Current State of the Art, Challenges, and Future Directions

Table 8

Enhanced protocols/algorithms for high control overheads in SMAC protocol.

Reference	Problem	Proposed solution/Purpose	Description	Limitations
[152]	High control overhead	AD-MAC	# An adaptive duty cycle is proposed where the duty cycle, particularly the sleep schedule, is altered to accommodate different traffic patterns.	# Packet delivery ratio and throughput not considered.
			# Minimized SMAC data frame headers and trailers by….
[138]	High control overhead	Adaptive energy-efficient MAC (AEEMAC)	AEEMAC protocol combines the SYNC and RTS control packets into one and RTS and ACK packets to reduce the number of control packet exchanges in the original SMAC.	# Comparative paper of AEEMAC with other MAC protocols.
[199]	High control overhead	Comparative paper of SMAC (synchronous MAC protocol) and RI-MAC (asynchronous duty cycle MAC protocol).	Performance analysis of SMAC and RI-MAC based on contending flow and data gathering scenarios.	# Missing improved SMAC’s high control overhead and energy consumption in a contending flow scenario.