Skip to content
🛠️ToolsShed

DNS Security Reference

Comprehensive DNSSEC and DNS security best practices reference including record types, attacks, and DoH vs DoT comparison.

DnsSecurityReference.dnssecTitle

DnsSecurityReference.dnssecDesc

DNSKEY

Contains the public key used to verify signatures in the zone.

RRSIG

Resource Record Signature — cryptographic signature over a DNS record set.

DS

Delegation Signer — links a child zone's DNSKEY to the parent zone.

NSEC

Next Secure — proves non-existence of a DNS record (authenticated denial).

NSEC3

Hashed version of NSEC — prevents zone walking by hashing owner names.

CDS

Child DS — child zone signals key changes to parent for automated rollover.

About this tool

DNS (Domain Name System) is the internet's address book, translating human-readable domain names into IP addresses—but traditional DNS operates unencrypted, making it vulnerable to spoofing, cache poisoning, and man-in-the-middle attacks that can redirect you to malicious websites. DNSSEC (DNS Security Extensions) solves this by adding cryptographic authentication to DNS responses, ensuring that records haven't been tampered with, while DNS over HTTPS (DoH) and DNS over TLS (DoT) encrypt your queries to prevent eavesdropping and tracking. Understanding these technologies is critical for system administrators, developers, security professionals, and anyone concerned about protecting their DNS traffic from surveillance or attacks.

This DNS Security Reference tool provides comprehensive documentation of DNSSEC record types (DNSKEY, RRSIG, DS, NSEC/NSEC3), common DNS attacks (spoofing, DDoS amplification, hijacking, NXDOMAIN attacks), and detailed comparisons between DNS encryption protocols—particularly the privacy and implementation differences between DoH (port 443, indistinguishable from web traffic) and DoT (port 853, easier to monitor on corporate networks). Whether you're configuring DNSSEC for your domain, choosing between DoH and DoT for your organization, or learning DNS security best practices, this tool consolidates scattered knowledge into one searchable reference.

The tool is ideal for domain administrators enabling DNSSEC (requiring DNS provider support and registrar DS record configuration), network engineers designing encrypted DNS solutions for their infrastructure, security practitioners auditing DNS policies, and developers building DNSSEC-aware applications or secure DNS clients. For long-term data protection, browser-based references like this are most useful in combination with hands-on testing via tools like dnsviz.net or the dig command-line utility.

Frequently Asked Questions

Code Implementation

import subprocess

# Query DNSSEC records using dig
def check_dnssec(domain: str) -> None:
    print(f"Checking DNSSEC for: {domain}")

    # Check DNSKEY record
    result = subprocess.run(
        ["dig", "+dnssec", "DNSKEY", domain],
        capture_output=True, text=True
    )
    if "DNSKEY" in result.stdout:
        print(f"  ✓ DNSKEY record found")
    else:
        print(f"  ✗ No DNSKEY record")

    # Check DS record at parent
    result = subprocess.run(
        ["dig", "+dnssec", "DS", domain],
        capture_output=True, text=True
    )
    if "DS" in result.stdout:
        print(f"  ✓ DS record found (DNSSEC enabled)")
    else:
        print(f"  ✗ No DS record (DNSSEC not fully configured)")

    # Check RRSIG
    result = subprocess.run(
        ["dig", "+dnssec", "A", domain],
        capture_output=True, text=True
    )
    if "RRSIG" in result.stdout:
        print(f"  ✓ RRSIG present (records are signed)")
    else:
        print(f"  ✗ No RRSIG (records not signed)")

check_dnssec("cloudflare.com")

Comments & Feedback

Comments are powered by Giscus. Sign in with GitHub to leave a comment.