Which term identifies the process of resolving host names to IP addresses by updating DNS records when addresses change?

• A. Dynamic DNS (DDNS)
• B. Dynamic IP
• C. Encryption
• D. Domain

Answer: (A)

Dynamic DNS is the mechanism that keeps a hostname pointed at the current IP address even when the address changes. Normally DNS maps a name to an IP, but if your device sits behind an ISP that changes your public IP, that mapping would quickly go out of date. Dynamic DNS automates updating the DNS record whenever the IP changes, so the same hostname continues to resolve to the correct address. A tiny client on your router or device detects the IP change and communicates with the DNS provider to refresh the A or AAAA record accordingly. This is especially useful for home networks or small offices that need remote access without paying for a static IP.

The other terms don’t describe this updating process. A dynamic IP is simply an address that can change, not the process of keeping DNS in sync. Encryption refers to protecting data confidentiality, not updating DNS records. A domain is part of the DNS namespace, but it’s the name itself—not the automatic update mechanism.