ICND1: Interconnecting Cisco Networking Devices Part 1 (CCENT, legacy) — Question 16

For which two reasons was RFC 1918 address space define? (Choose two)

Answer options

• A. to preserve public IPv4 address space
• B. to reduce the occurrence of overlapping IP addresses
• C. to preserve public IPv6 address space
• D. reduce the size of ISP routing tables
• E. to support the NAT protocol

Correct answer: D, E

Explanation

The correct answers are D and E. RFC 1918 was created to reduce the size of ISP routing tables by allowing private IP addresses that do not need to be routed on the public internet, and to support the NAT protocol which enables multiple devices on a local network to share a single public IP address. Options A and C are incorrect as they do not relate to the specific purposes of RFC 1918, and B is less relevant to the main objectives.