DNS parameters (IANA registry)

Assigned Domain Name System (DNS) parameters from the IANA DNS Parameters registry: resource record (RR) TYPEs, RCODEs, CLASSes, and OpCodes, one document per assigned value with its meaning, references, and template or registration date where the registry lists them. Unassigned values and ranges are omitted; registrant contact handles inside references are replaced by a placeholder.

Browse 137 documents Use with your agent

Documents

Showing 1–24 of 137 documents

Document	Version
CLASS Chaos (CH) (3) DNS CLASS Chaos (CH) (decimal 3, hexadecimal 0x0003) in the IANA Domain Name System (DNS) Parameters registry.	v1
CLASS Hesiod (HS) (4) DNS CLASS Hesiod (HS) (decimal 4, hexadecimal 0x0004) in the IANA Domain Name System (DNS) Parameters registry.	v1
CLASS Internet (IN) (1) DNS CLASS Internet (IN) (decimal 1, hexadecimal 0x0001) in the IANA Domain Name System (DNS) Parameters registry.	v1
CLASS QCLASS * (ANY) (255) DNS CLASS QCLASS * (ANY) (decimal 255, hexadecimal 0x00FF) in the IANA Domain Name System (DNS) Parameters registry.	v1
CLASS QCLASS NONE (254) DNS CLASS QCLASS NONE (decimal 254, hexadecimal 0x00FE) in the IANA Domain Name System (DNS) Parameters registry.	v1
CLASS Reserved (0) DNS CLASS Reserved (decimal 0, hexadecimal 0x0000) in the IANA Domain Name System (DNS) Parameters registry.	v1
CLASS Reserved (65535) DNS CLASS Reserved (decimal 65535, hexadecimal 0xFFFF) in the IANA Domain Name System (DNS) Parameters registry.	v1
OpCode DNS Stateful Operations (DSO) (6) DNS OpCode DNS Stateful Operations (DSO) (value 6) in the IANA Domain Name System (DNS) Parameters registry.	v1
OpCode IQuery (Inverse Query, OBSOLETE) (1) DNS OpCode IQuery (Inverse Query, OBSOLETE) (value 1) in the IANA Domain Name System (DNS) Parameters registry.	v1
OpCode Notify (4) DNS OpCode Notify (value 4) in the IANA Domain Name System (DNS) Parameters registry.	v1
OpCode Query (0) DNS OpCode Query (value 0) in the IANA Domain Name System (DNS) Parameters registry.	v1
OpCode Status (2) DNS OpCode Status (value 2) in the IANA Domain Name System (DNS) Parameters registry.	v1
OpCode Update (5) DNS OpCode Update (value 5) in the IANA Domain Name System (DNS) Parameters registry.	v1
RCODE BADALG (21) DNS RCODE BADALG (value 21) in the IANA Domain Name System (DNS) Parameters registry: Algorithm not supported.	v1
RCODE BADCOOKIE (23) DNS RCODE BADCOOKIE (value 23) in the IANA Domain Name System (DNS) Parameters registry: Bad/missing Server Cookie.	v1
RCODE BADKEY (17) DNS RCODE BADKEY (value 17) in the IANA Domain Name System (DNS) Parameters registry: Key not recognized.	v1
RCODE BADMODE (19) DNS RCODE BADMODE (value 19) in the IANA Domain Name System (DNS) Parameters registry: Bad TKEY Mode.	v1
RCODE BADNAME (20) DNS RCODE BADNAME (value 20) in the IANA Domain Name System (DNS) Parameters registry: Duplicate key name.	v1
RCODE BADSIG (16) DNS RCODE BADSIG (value 16) in the IANA Domain Name System (DNS) Parameters registry: TSIG Signature Failure.	v1
RCODE BADTIME (18) DNS RCODE BADTIME (value 18) in the IANA Domain Name System (DNS) Parameters registry: Signature out of time window.	v1
RCODE BADTRUNC (22) DNS RCODE BADTRUNC (value 22) in the IANA Domain Name System (DNS) Parameters registry: Bad Truncation.	v1
RCODE BADVERS (16) DNS RCODE BADVERS (value 16) in the IANA Domain Name System (DNS) Parameters registry: Bad OPT Version.	v1
RCODE DSOTYPENI (11) DNS RCODE DSOTYPENI (value 11) in the IANA Domain Name System (DNS) Parameters registry: DSO-TYPE Not Implemented.	v1
RCODE FormErr (1) DNS RCODE FormErr (value 1) in the IANA Domain Name System (DNS) Parameters registry: Format Error.	v1

Source, review, and usage

Published on Koskamo by: Koskamo
Version: 138
Documents: 137 documents
Reviewed: 2026-10-05
Last approved change: 2026-10-05
Agent lookups: 0 in the last 90 days
Reuse: IANA Domain Name System (DNS) Parameters registry (iana.org/assignments/dns-parameters); registry data reproduced verbatim with references
Review status: Published by Koskamo; proposed revisions require Koskamo approval

Original sources are linked on each document. Owner approval records a publishing decision; it does not imply independent fact checking.

Use this dataset from an agent

Agents can query it without an account. POST to /api/v1/retrieve, or connect an MCP client and call koskamo_retrieve with dataset: "dns-parameters".

Set up your agent Read documents as JSON

The JSON endpoint returns document text and source links in pages. Use limit and offset to retrieve more records; total gives the dataset size.

retrieve request

curl --fail-with-body 'https://koskamo.com/api/v1/retrieve' -H 'Content-Type: application/json' --data-raw '{"query":"dns-parameters","dataset":"dns-parameters","top_k":3}'

Change history

Every change that reached this dataset. Proposals from contributors land only after Koskamo approves them.

Published by Koskamo2026-10-05
RR type EUI48 (108) · v1
Published by Koskamo2026-10-05
RR type SVCB (64) · v1
Published by Koskamo2026-10-04
OpCode DNS Stateful Operations (DSO) (6) · v1
Published by Koskamo2026-10-04
OpCode Update (5) · v1
Published by Koskamo2026-10-04
OpCode Notify (4) · v1
Published by Koskamo2026-10-04
OpCode Status (2) · v1
Published by Koskamo2026-10-04
OpCode IQuery (Inverse Query, OBSOLETE) (1) · v1
Published by Koskamo2026-10-04
OpCode Query (0) · v1
Published by Koskamo2026-10-04
CLASS Reserved (65535) · v1
Published by Koskamo2026-10-04
CLASS QCLASS * (ANY) (255) · v1