DNS RFC Reference

The DNS is defined by a large number of RFCs, many of which have been extensively updated or obsoleted. This chapter aims to provide a roadmap and reference for this confusing space. The chapter does not aim to be encyclopedically complete, however, as the key information would then be lost in the noise. The curious are encouraged to click on the “Updated by” links on the IETF pages to see the finer points, or the “Obsoletes” links to go spelunking into the history of the DNS.

DNSSEC gets its own section instead of being included in the “Core” list because there are many DNSSEC related RFCs and it’s helpful to group them together. It’s not a statement that DNSSEC isn’t part of the “Core” of the DNS.

The IANA DNS Parameters registry is the offical reference site for all DNS constants.

Core RFCs

RFC 1034
Introduction to the DNS and description of basic behavior.
RFC 1035
The core DNS wire protocol and master file format.
RFC 1995
Incremental zone transfer (IXFR).
RFC 1996
The NOTIFY protocol.
RFC 2181
Clarifications to the specification.
RFC 2308
Negative Caching.
RFC 2845
Transaction Sigatures (TSIG)
RFC 3007
Dynamic Updates
RFC 3645

GSS-TSIG.

Note that dnspython does not currently have GSS-TSIG support. GSS-TSIG is most frequently used when updating Microsoft Active-Directory-based DNS servers.

RFC 5936
Zone transfers (AXFR).
RFC 6891
EDNS (version 0)
RFC 8020
Clarification on the meaning of NXDOMAIN.

DNSSEC RFCs

RFC 4033
Introduction and requirements.
RFC 4034
Resource records.
RFC 4035
Protocol.
RFC 4470
Minimally covering NSEC records and On-line Signing.
RFC 6840
Clarifications and implementation Notes.

Misc RFCs

RFC 1101
Reverse mapping name form for IPv4.
RFC 1982
Serial number arithmetic.
RFC 4343
Case-sensitivity clarification.

RFCs for RR types

There are many more RR types than are listed here; if a type is not listed it means it is obsolete, deprecated, or rare “in the wild”. Some newer types that are currently rare are listed because they may well be more heavily used in the not-to-distant future. See the IANA DNS Parameters registry for a complete list.

A
RFC 1035
AAAA
RFC 3596
CDS
RFC 7344
CDNSKEY
RFC 7344
CNAME
RFC 1035
CSYNC
RFC 7477
DNAME
RFC 6672
DNSKEY
RFC 4034
DS
RFC 4034
LOC
RFC 1876
MX
RFC 1035
NAPTR
RFC 3403
NS
RFC 1035
NSEC
RFC 4034
NSEC3
RFC 5155
NSEC3PARAM
RFC 5155
OPENPGPKEY
RFC 7929
PTR
RFC 1035
RRSIG
RFC 4034
SOA
RFC 1035
SPF
RFC 7208
SRV
RFC 2782
TLSA
RFC 6698
TXT
RFC 1035