RRSIG (Resource Record Signature) records are cryptographic signatures used in DNSSEC (DNS Security Extensions) to authenticate DNS data. They provide integrity and authenticity verification for DNS responses, protecting against DNS spoofing and cache poisoning attacks.

Key Components:

• Type Covered: The DNS record type that this signature covers (A, MX, NS, etc.)
• Algorithm: The cryptographic algorithm used for signing (RSA/SHA-256, ECDSA, etc.)
• Signature Expiration: When the signature expires and needs renewal
• Key Tag: Identifier for the DNSKEY used to create this signature
• Signature: The actual cryptographic signature data

How RRSIG Records Work:

1. DNS zone owner creates DNSKEY records containing public keys
2. Private keys are used to sign DNS records, creating RRSIG records
3. Resolvers verify signatures using the corresponding DNSKEY records
4. Chain of trust is established through DS records in parent zones