List of Figures

Figure 1.	Message Authentication	6

Figure 2.	NTPv4 Autokey	6

Figure 3.	Constructing the Key List	7

Figure 4.	Transmitting Messages	8

Figure 5.	NTP Secure Groups	9

Figure 6.	Hierarchical Overlapping Groups	10

Figure 7.	Multiple Overlapping Groups	11

Figure 8.	Identity Exchange	12

Figure 9.	Status Word	18

Figure 10.	NTP Header Format	29

Figure 11.	NTP Extension Field Format	30

Figure 12.	Private Certificate (PC) Identity Scheme	41

Figure 13.	Trusted Certificate (TC) Identity Scheme	42

Figure 14.	Schnorr (IFF) Identity Scheme	43

Figure 15.	Guillard-Quisquater (GQ) Identity Scheme	45

Figure 16.	Mu-Varadharajan (MV) Identity Scheme	47