Systems Security Certified Practitioner (SSCP) — Question 4

In the days before CIDR (Classless Internet Domain Routing), networks were commonly organized by classes. Which of the following would have been true of a
Class B network?

Answer options

• A. The first bit of the IP address would be set to zero.
• B. The first bit of the IP address would be set to one and the second bit set to zero.
• C. The first two bits of the IP address would be set to one, and the third bit set to zero.
• D. The first three bits of the IP address would be set to one.

Correct answer: C

Explanation

A Class B network is defined by the first two bits being set to one and the third bit being set to zero, which corresponds to option C. Option A is incorrect because Class B does not have the first bit set to zero. Option B is incorrect as it misrepresents the bit settings for Class B. Option D is also wrong since Class B does not have the first three bits set to one.