RFC 4343: Domain Name System (DNS) Case Insensitivity Clarification

Domain Name System (DNS) names are "case insensitive". This document explains exactly what that means and provides a clear specification of the rules. This…

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Outgoing relationships (15 related RFCs)

Updates — RFC 1035: Domain names - implementation and specification
Updates — RFC 1034: Domain names - concepts and facilities
Updates — RFC 2181: Clarifications to the DNS Specification
Informative reference — RFC 3490: Internationalizing Domain Names in Applications (IDNA)
Informative reference — RFC 3454: Preparation of Internationalized Strings ("stringprep")
Informative reference — RFC 3492: Punycode: A Bootstring encoding of Unicode for Internationalized Domain Names in Applications (IDNA)
Informative reference — RFC 2606: Reserved Top Level DNS Names
Informative reference — RFC 2671: Extension Mechanisms for DNS (EDNS0)
Informative reference — RFC 3491: Nameprep: A Stringprep Profile for Internationalized Domain Names (IDN)
Informative reference — RFC 1591: Domain Name System Structure and Delegation
Informative reference — RFC 3363: Representing Internet Protocol version 6 (IPv6) Addresses in the Domain Name System (DNS)
Informative reference — RFC 1183: New DNS RR Definitions
Informative reference — RFC 2673: Binary Labels in the Domain Name System
Informative reference — RFC 2929: Domain Name System (DNS) IANA Considerations
Informative reference — RFC 3092: Etymology of "Foo"

Incoming relationships (12 related RFCs)

Updated by — RFC 5890: Internationalized Domain Names for Applications (IDNA): Definitions and Document Framework
Normatively referenced by — RFC 5922: Domain Certificates in the Session Initiation Protocol (SIP)
Normatively referenced by — RFC 7489: Domain-based Message Authentication, Reporting, and Conformance (DMARC)
Normatively referenced by — RFC 8801: Discovering Provisioning Domain Names and Data
Normatively referenced by — RFC 8737: Automated Certificate Management Environment (ACME) TLS Application-Layer Protocol Negotiation (ALPN) Challenge Extension
Normatively referenced by — RFC 9517: A URN Namespace for the Data Documentation Initiative (DDI)
Normatively referenced by — RFC 9989: Domain-Based Message Authentication, Reporting, and Conformance (DMARC)
Informatively referenced by — RFC 6125: Representation and Verification of Domain-Based Application Service Identity within Internet Public Key Infrastructure Using X.509 (PKIX) Certificates in the Context of Transport Layer Security (TLS)
Informatively referenced by — RFC 5894: Internationalized Domain Names for Applications (IDNA): Background, Explanation, and Rationale
Informatively referenced by — RFC 6895: Domain Name System (DNS) IANA Considerations
Informatively referenced by — RFC 9525: Service Identity in TLS
Informatively referenced by — RFC 6195: Domain Name System (DNS) IANA Considerations