CyberCertPrepNetwork FundamentalsDNS & DHCPEASYFree question
Scenario
A developer at a startup wants to access their home media server (dynamic IP from ISP) from anywhere using the hostname 'media.mydev.home'. Their ISP changes the home IP roughly every 3-7 days.
What service and DNS mechanism allows this, and how does the automatic IP update work?
- A.IPv6 SLAAC provides a permanent address; the developer should use an IPv6 address with a standard DNS record
- B.A static IP from the ISP is required; dynamic IPs cannot be used with any DNS service
- C.The developer must manually update the DNS A record every time the ISP changes the IP; no automation exists for this; root hints are downloaded from the TLD servers each time the resolver restarts. An NS delegation must point at an IP address, since nameservers cannot be named
- D.Dynamic DNS (DDNS) service (e.g., No-IP, DuckDNS, Cloudflare DDNS): a DDNS client software on the home router (or server) detects IP changes and sends authenticated updates to the DDNS provider's API; the provider updates the DNS A record with the new IP. Very low TTL values (60-300 seconds) ensure clients pick up IP changes quickly
Why D is correct