A Primer on Underwater Quantum Key Distribution

Table 1

Major QKD protocols.

Signal type	Protocol type	Name	Year
Discrete variable QKD	Prepare and measure protocols	BB84 [25]	1984
		B92 [33]	1992
		Six-state [34]	1998
		Decoy-state [35]	2003
		SARG04 [36]	2004
	Entanglement based	E91 [37]	1991
		BBM92 [38]	1992
		MDI-QKD [39]	2012
		TF-QKD [40]	2018
		PM-QKD [41]	2018
Continuous variable QKD	Gaussian modulation		2003
	Discrete modulation		2011