Cisco Certified Support Technician (CCST) NetworkingNetworking FundamentalsHard

A network engineer is configuring a router to connect a corporate network to the internet. The router needs to translate private IP addresses used within the corporate network to a single public IP address when communicating with external hosts. Which specific function is being configured on the router?

  1. AARP (Address Resolution Protocol)
  2. BDHCP (Dynamic Host Configuration Protocol)
  3. CDNS (Domain Name System)
  4. DNAT (Network Address Translation)
Show answer & explanation

Correct answer: D. NAT (Network Address Translation)

Network Address Translation (NAT) is the specific function that allows multiple devices on a private network to share a single public IP address when accessing the internet. It translates private IP addresses to a public one and vice versa, which is essential for conserving IPv4 public addresses and providing a layer of security.

Why the other options are wrong

  • A. ARP resolves IP addresses to MAC addresses within a local network segment; it is not involved in private-to-public IP address translation.
  • B. DHCP automatically assigns IP addresses to devices on a network; it does not translate addresses for internet access.
  • C. DNS translates domain names into IP addresses; it is not involved in private-to-public IP address translation.

Network Address Translation (NAT)

NAT is a method of remapping one IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device.

  • Primarily used to conserve public IPv4 addresses.
  • Allows multiple private IP addresses to share a single public IP.
  • Provides a basic form of security by hiding internal network structure.

Memory trick: NAT is the Name for Address Translation.

More Networking Fundamentals questions