JNCIE-ENT: Juniper Networks Certified Expert – Enterprise Routing and Switching — Question 10

When discussing network reliability, what does the term "five nines" mean?

Answer options

• A. The network is up 99.999% of the time.
• B. The network is up .99999% of the time.
• C. The network is up 9.9999% of the time.
• D. The network is up .09999% of the time.

Correct answer: A

Explanation

The correct answer, A, refers to a network being operational 99.999% of the time, which is a standard measure of high reliability. Options B, C, and D represent significantly lower percentages of uptime, which do not align with the definition of 'five nines' in the context of network reliability.