DNSSEC: Why You Should Enable It

## The Problem DNSSEC Solves The Domain Name System was designed in the early 1980s for a small, trusted network. Security was not a design goal. As a result, a basic DNS query has no way to verify that the answer it receives is authentic — any party between your resolver and the authoritative name server could substitute a forged answer. This vulnerability is known as DNS spoofing or DNS cache poisoning. An attacker who can inject a false DNS response can silently redirect your visitors to a server they control — a server that might serve malware, harvest credentials, or simply impersonate your website. The user's browser shows your domain name in the address bar; nothing looks wrong. DNSSEC (DNS Security Extensions) closes this gap by adding cryptographic signatures to DNS records. A resolver that supports DNSSEC can verify that the answer it received was signed by the legitimate owner of the zone and has not been tampered with in transit. ## How DNSSEC Works DNSSEC builds a **chain of trust** from the root of the DNS hierarchy down to your domain. At each level, the zone owner signs their DNS records with a private key and publishes a corresponding public key. Resolvers work up the chain to verify signatures: 1. **Root zone** — The DNS root is signed. ICANN publishes and manages the root key. 2. **TLD zone** — Each TLD registry signs its zone (`.com`, `.org`, `.io`, etc.) and has its key verified by the root. 3. **Your domain zone** — You (via your registrar) sign your domain's records and publish a **DS record** (Delegation Signer) in the parent TLD zone, linking your key into the chain. When a DNSSEC-validating resolver queries your domain, it walks this chain. If any signature fails or is missing, the resolver returns a `SERVFAIL` error rather than an unverified (potentially spoofed) answer. ## What DNSSEC Protects Against - **Cache poisoning**: Attackers injecting false records into a resolver's cache. - **Man-in-the-middle DNS interception**: Forged responses from a compromised network path. - **BGP hijacking of DNS infrastructure**: Route hijacks that redirect DNS traffic to attacker-controlled resolvers. ## What DNSSEC Does Not Protect Against DNSSEC authenticates DNS *data*. It does not: - Encrypt DNS queries (use DNS-over-HTTPS or DNS-over-TLS for that). - Protect against Domain Hijacking (securing your registrar account does that). - Replace SSL/TLS — you still need HTTPS for encrypted web traffic. Think of DNSSEC as guaranteeing the *authenticity* of your address book entry, while SSL/TLS encrypts the *conversation* once you arrive. ## Checking DNSSEC Status Use WHOIS Lookup Tool to look at your domain's status fields and DNS Record Helper to inspect your DS records. You can also query directly: ``` dig example.com DS +short ``` If a DS record is returned, DNSSEC is active. You can further validate the chain using an online DNSSEC debugger (ICANN's DNSSEC Debugger is a reliable tool). ## Enabling DNSSEC at Your Registrar For most domain owners using a registrar's built-in DNS hosting, enabling DNSSEC is a single toggle in the DNS settings panel. The registrar generates the key pair, signs the zone, and publishes the DS record in the parent zone automatically. **Steps for registrar-managed DNS:** 1. Log in to your registrar account. 2. Navigate to the domain's DNS or security settings. 3. Find "DNSSEC" and click Enable (or "Activate DNSSEC"). 4. Wait 24–48 hours for the DS record to propagate. 5. Validate using a DNSSEC debugger. **Steps for third-party DNS providers (Cloudflare, Route 53, etc.):** If you use a DNS provider separate from your registrar, the provider signs the zone and gives you a DS record (or DNSKEY hash) to add at your registrar. The process: 1. Enable DNSSEC in your DNS provider's dashboard. 2. Copy the DS record values provided. 3. Log in to your registrar and paste the DS record into the DNSSEC / DS record field. 4. Propagation takes up to 48 hours. ## Risks of Misconfiguration DNSSEC is a sign-and-serve system. If you change DNS providers or make certain DNS changes without updating the DS record at the parent, resolvers will fail to validate your zone and return `SERVFAIL` errors — effectively making your domain unreachable for users whose resolvers enforce DNSSEC. **Key operational rules:** - When migrating DNS providers, disable DNSSEC **before** the migration, complete the migration, then re-enable it with the new provider's keys. - Set a calendar reminder to monitor key rotation — most providers handle this automatically, but confirm. - Keep your registrar and DNS provider in sync. A stale DS record at the registrar breaks the chain. ## TLD Support Almost all major gTLDs (`.com`, `.net`, `.org`, `.io`, `.co`, etc.) and most ccTLDs support DNSSEC. A small number of older ccTLDs do not. Check your registrar's DNSSEC settings to confirm support for your specific TLD. ## Should You Enable DNSSEC? Yes — for any domain you care about. The setup is now mostly automated, the ongoing management is handled by your registrar or DNS provider, and the protection is real. The only reason to delay is if your registrar does not support it for your TLD, in which case consider moving to a registrar that does. See Domain Security Checklist for DNSSEC as part of a complete security posture.