Systems Security Certified Practitioner – SSCP – Question0830 - Systems Security Certified Practitioner

Which of the following is an IP address that is private (i.e. reserved for internal networks, and not a valid address to use on the Internet)?

A. 172.12.42.5
B. 172.140.42.5
C. 172.31.42.5
D. 172.15.42.5

Correct Answer: C

Explanation:

This is a valid Class B reserved address. For Class B networks, the reserved addresses are 172.16.0.0 -172.31.255.255.
The private IP address ranges are defined within RFC 1918:
RFC 1918 private ip address range

The following answers are incorrect:
172.12.42.5 Is incorrect because it is not a Class B reserved address.
172.140.42.5 Is incorrect because it is not a Class B reserved address.
172.15.42.5 Is incorrect because it is not a Class B reserved address.