A network security analyst is auditing border firewall traffic logs to ensure no unroutable internal addresses are leaked to the public Internet. Corporate security policy requires Network Address Translation (NAT) for all internal devices accessing public web services.
Which TWO IPv4 addresses identified in the firewall log belong to the RFC 1918 private address space and require source NAT before being routed across the public Internet? (Select two.)
- 10.254.1.5Answer
- 172.30.100.45Answer
- C172.32.50.10
- D192.169.10.1
Answer
The addresses 10.254.1.5 and 172.30.100.45 are RFC 1918 private IPv4 addresses that require Network Address Translation to be routed over the public Internet.
RFC 1918 defines three private IPv4 address blocks that are not routable across the public Internet: 10.0.0.0/8, 172.16.0.0/12 (172.16.0.0 through 172.31.255.255), and 192.168.0.0/16. The address 10.254.1.5 falls inside the 10.0.0.0/8 Class A block, and 172.30.100.45 falls inside the 172.16.0.0/12 Class B block. Both require source NAT to communicate over public networks.
Step-by-Step Solution
Key Concept
RFC 1918 Private IPv4 Addressing Ranges
Estimated Time:1m 15s