Experimental Simulation-Based Performance Evaluation of an SMS-Based Emergency Geolocation Notification System

Table 1

Table used for deductions that compares the availability and the corresponding downtime [28].

Availability	Downtime
90% (1 nine)	36.5 days/year
99% (2 nines)	3.65 days/year
99.9% (3 nines)	8.76 hours/year
99.99% (4 nines)	52 minutes/year
99.999% (5 nines)	5 minutes/year
99.9999% (6 nines)	31 seconds/year