Systems Security Certified Practitioner – SSCP – Question0831

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. 10.0.42.5
B. 11.0.42.5
C. 12.0.42.5
D. 13.0.42.5

Correct Answer: A

Explanation:

This is a valid Class A reserved address. For Class A, the reserved addresses are 10.0.0.0 -10.255.255.255.
The following answers are incorrect:
11.0.42.5
Is incorrect because it is not a Class A reserved address.
12.0.42.5
Is incorrect because it is not a Class A reserved address.
13.0.42.5
Is incorrect because it is not a Class A reserved address.
The private IP address ranges are defined within RFC 1918:
RFC 1918 private ip address range

References: 3Com http://www.3com.com/other/pdfs/infra/corpinfo/en_US/501302.pdf AIOv3 Telecommunications and Networking Security (page 438)