List of RFCs

Here we provide a list of implemented RFCs, though it may not be 100% complete. Normal users shouldn’t need to look here; they might search the docs instead.

Note that in some cases only part of the RFC is covered, as some parts are optional to a degree or even not relevant to DNS resolvers.

RFC 1034

Domain Names – Concepts and Facilities

RFC 1035

Domain Names – Implementation and Specifciation

RFC 1101

DNS Encoding of Network Names and Other Types

RFC 1123

Requirements for Internet Hosts – Application and Support

RFC 1521

MIME (Multipurpose Internet Mail Extensions) Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies

RFC 1876

A Means for Expressing Location Information in the Domain Name System

RFC 2181

Clarifications to the DNS Specification

RFC 2230

Key Exchange Delegation Record for the DNS

RFC 2308

Negative Caching of DNS Queries (DNS NCACHE)

RFC 2535

Domain Name System Security Extensions

This variant of DNSSEC has been obsolete for many years, but we stil support those RRs (in zonefile and wire).

RFC 2538

Storing Certificates in the Domain Name System (DNS)

The RFC is obsolete, but we still support those RRs (in zonefile and wire).

RFC 2606

Reserved Top Level DNS Names

RFC 2671

Extension Mechanisms for DNS (EDNS0)

Well, the EDNS0 definition has been rewritten as RFC 6891 which we really support.

RFC 2672

Non-Terminal DNS Name Redirection

Well, the DNAME definition has been rewritten as RFC 6672 which we really support.

RFC 2782

A DNS RR for specifying the location of services (DNS SRV)

RFC 2915

The Naming Authority Pointer (NAPTR) DNS Resource Record

RFC 3123

A DNS RR Type for Lists of Address Prefixes (APL RR)

This is probably unused in practice, but we still support the APL RR (in zonefile and wire).

RFC 3225

Indicating Resolver Support of DNSSEC

This is the DO bit in DNS messages.

RFC 3526

More Modular Exponential (MODP) Diffie-Hellman groups for Internet Key Exchange (IKE)

RFC 3597

Handling of Unknown DNS Resource Record (RR) Types

RFC 4007

IPv6 Scoped Address Architecture

RFC 4025

A Method for Storing IPsec Keying Material in DNS

RFC 4033

DNS Security Introduction and Requirements

RFC 4034

Resource Records for the DNS Security Extensions

RFC 4035

Protocol Modifications for the DNS Security Extensions

RFC 4255

Using DNS to Securely Publish Secure Shell (SSH) Key Fingerprints

RFC 4343

Domain Name System (DNS) Case Insensitivity Clarification

RFC 4398

Storing Certificates in the Domain Name System (DNS)

RFC 4509

Use of SHA-256 in DNSSEC Delegation Signer (DS) Resource Records (RRs)

RFC 4592

The Role of Wildcards in the Domain Name System

RFC 4697

Observed DNS Resolution Misbehavior

RFC 4701

A DNS Resource Record (RR) for Encoding Dynamic Host Configuration Protocol (DHCP) Information (DHCID RR)

RFC 5001

DNS Name Server Identifier (NSID) Option

See Name Server Identifier (NSID)

RFC 5011

Automated Updates of DNS Security (DNSSEC) Trust Anchors

See inside DNSSEC, data verification

RFC 5114

Additional Diffie-Hellman Groups for Use with IETF Standards

RFC 5155

DNS Security (DNSSEC) Hashed Authenticated Denial of Existence

RFC 5358

Preventing Use of Recursive Nameservers in Reflector Attacks

RFC 5452

Measures for Making DNS More Resilient against Forged Answers

RFC 5702

Use of SHA-2 Algorithms with RSA in DNSKEY and RRSIG Resource Records for DNSSEC

RFC 6147

DNS64: DNS Extensions for Network Address Translation from IPv6 Clients to IPv4 Servers

See DNS64

RFC 6234

US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)

RFC 6303

Locally Served DNS Zones

RFC 6598

IANA-Reserved IPv4 Prefix for Shared Address Space

RFC 6604

xNAME RCODE and Status Bits Clarification

RFC 6605

Elliptic Curve Digital Signature Algorithm (DSA) for DNSSEC

RFC 6672

DNAME Redirection in the DNS

RFC 6698

The DNS-Based Authentication of Named Entities (DANE) Transport Layer Security (TLS) Protocol: TLSA

We support the record, but not authenticating by it.

RFC 6725

DNS Security (DNSSEC) DNSKEY Algorithm IANA Registry Updates

RFC 6742

DNS Resource Records for the Identifier-Locator Network Protocol (ILNP)

RFC 6761

Special-Use Domain Names

RFC 6840

Clarifications and Implementation Notes for DNS Security (DNSSEC)

RFC 6844

DNS Certification Authority Authorization (CAA) Resource Record

RFC 6891

Extension Mechanisms for DNS (EDNS(0))

RFC 7043

Resource Records for EUI-48 and EUI-64 Addresses in the DNS

RFC 7344

Automating DNSSEC Delegation Trust Maintenance

RFC 7413

TCP Fast Open

We only support it on the server side.

RFC 7477

Child-to-Parent Synchronization in DNS

RFC 7553

The Uniform Resource Identifier (URI) DNS Resource Record

RFC 7646

Definition and Use of DNSSEC Negative Trust Anchors

See inside DNSSEC, data verification

RFC 7686

The “.onion” Special-Use Domain Name

RFC 7706

Decreasing Access Time to Root Servers by Running One on Loopback

Obsoleted by RFC 8806; see also Cache prefilling

RFC 7766

DNS Transport over TCP - Implementation Requirements

RFC 7830

The EDNS(0) Padding Option

See inside DoT and DoH (encrypted DNS)

RFC 7858

Specification for DNS over Transport Layer Security (TLS)

See DNS-over-TLS (DoT) and Forwarding.

RFC 7929

DNS-Based Authentication of Named Entities (DANE) Bindings for OpenPGP

RFC 7958

DNSSEC Trust Anchor Publication for the Root Zone

Though typical Knot Resolver packaging uses a different approach.

RFC 8080

Edwards-Curve Digital Security Algorithm (EdDSA) for DNSSEC

RFC 8145

Signaling Trust Anchor Knowledge in DNS Security Extensions (DNSSEC)

See Signaling Trust Anchor Knowledge in DNSSEC

RFC 8162

Using Secure DNS to Associate Certificates with Domain Names for S/MIME

RFC 8198

Aggressive Use of DNSSEC-Validated Cache

See Cache

RFC 8310

Usage Profiles for DNS over TLS and DNS over DTLS

RFC 8375

Special-Use Domain ‘home.arpa.’

RFC 8467

Padding Policies for Extension Mechanisms for DNS (EDNS(0))

See inside DoT and DoH (encrypted DNS)

RFC 8482

Providing Minimal-Sized Responses to DNS Queries That Have QTYPE=ANY

This RFC was focused on authoritative servers. As a resolver, we shouldn’t just make up data on arbitrary names, so we really use a different minimization method currently: reply with RCODE=NOTIMPL.

RFC 8484

DNS Queries over HTTPS (DoH)

See DNS-over-HTTPS (DoH)

RFC 8509

A Root Key Trust Anchor Sentinel for DNSSEC

See Sentinel for Detecting Trusted Root Keys

RFC 8624

Algorithm Implementation Requirements and Usage Guidance for DNSSEC

RFC 8767

Serving Stale Data to Improve DNS Resiliency

See Serve stale

RFC 8806

Running a Root Server Local to a Resolver

See Cache prefilling

RFC 8914

Extended DNS Errors

RFC 8976

Message Digest for DNS Zones

RFC 9077

NSEC and NSEC3: TTLs and Aggressive Use

RFC 9156

DNS Query Name Minimisation to Improve Privacy

Our current code doesn’t use full minimization but a compromise approach, which in practice mainly minimizes queries going to root and TLD servers. We also have a fallback that deals with typical cases of non-conforming servers.

RFC 9210

DNS Transport over TCP - Operational Requirements