CREST Practitioner Security Analyst (CPSA) Practice

What is the primary purpose of Network Address Translation (NAT)?

1. To hide internal IP addresses

2. To create multiple public IPs

3. To assign static IP addresses

4. To monitor network traffic

The correct answer is: To hide internal IP addresses

The primary purpose of Network Address Translation (NAT) is to hide internal IP addresses. NAT works by allowing a router to modify the IP address information within the header of IP packets while they are in transit across a traffic routing device. This functionality enables the use of private IP addresses within a local network while only exposing a single public IP address to the external network. By keeping the internal IP addresses hidden, NAT enhances the security of the internal network by making it more difficult for external entities to ascertain the structure or devices within that network. Consequently, this method protects devices from direct access from outside networks and mitigates the risk of threats targeting those internal addresses. Other options, such as creating multiple public IPs or assigning static IP addresses, do not accurately reflect the core purpose of NAT. While NAT can enable multiple devices on a local network to share a single public IP address, this is a means to an end rather than the primary objective. Similarly, NAT does not deal with static IP assignments, which are part of IP address management rather than the translation function. Monitoring network traffic is also not a role of NAT; it is primarily concerned with the transformation of address information, rather than analyzing or tracking traffic flow.