RFC 1035 · November 1987 · P. Mockapetris
Domain names - implementation and specification
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Built by hand from RFC 1035. Every arrow, step and field cites the RFC sentence it comes from, and an automated test checks each quote against the RFC text. Provisional: not yet reviewed by a second engineer. Help verify this visual
RFC 1035 §4.1 All communications inside of the domain protocol are carried in a single format called a message.
1. Resolver → Name server: query
The resolver sends a query message and gives it an ID of its choosing.
RFC 1035 §4.1.1ID A 16 bit identifier assigned by the program that generates any kind of query.
2. Name server → Resolver: reply
The name server copies the ID into its reply, so the resolver can tell which outstanding query the reply belongs to.
RFC 1035 §4.1.1This identifier is copied the corresponding reply and can be used by the requester to match up replies to outstanding queries.
Not shown: Opcode and RCODE value tables (§4.1.1); Resource record format: NAME, TYPE, CLASS, TTL, RDLENGTH, RDATA (§4.1.3); Message compression with pointers (§4.1.4); Transport: UDP size limit and truncation, TCP two-byte length prefix (§4.2); Resolver details: SLIST, retransmission and response matching (§7); Master file format, name server internals, inverse queries (§5, §6).
Lineage
Updated by (29)
- RFC 9619 — In the DNS, QDCOUNT Is (Usually) One
- RFC 8767 — Serving Stale Data to Improve DNS Resiliency
- RFC 8490 — DNS Stateful Operations
- RFC 8482 — Providing Minimal-Sized Responses to DNS Queries That Have QTYPE=ANY
- RFC 7766 — DNS Transport over TCP - Implementation Requirements
- RFC 6604 — xNAME RCODE and Status Bits Clarification
- RFC 5966 — DNS Transport over TCP - Implementation Requirements
- RFC 5936 — DNS Zone Transfer Protocol (AXFR)
- RFC 4343 — Domain Name System (DNS) Case Insensitivity Clarification
- RFC 4035 — Protocol Modifications for the DNS Security Extensions
- RFC 4034 — Resource Records for the DNS Security Extensions
- RFC 4033 — DNS Security Introduction and Requirements
- RFC 3658 — Delegation Signer (DS) Resource Record (RR)
- RFC 3425 — Obsoleting IQUERY
- RFC 2845 — Secret Key Transaction Authentication for DNS (TSIG)
- RFC 2673 — Binary Labels in the Domain Name System
- RFC 2535 — Domain Name System Security Extensions
- RFC 2308 — Negative Caching of DNS Queries (DNS NCACHE)
- RFC 2181 — Clarifications to the DNS Specification
- RFC 2137 — Secure Domain Name System Dynamic Update
- RFC 2136 — Dynamic Updates in the Domain Name System (DNS UPDATE)
- RFC 2065 — Domain Name System Security Extensions
- RFC 1996 — A Mechanism for Prompt Notification of Zone Changes (DNS NOTIFY)
- RFC 1995 — Incremental Zone Transfer in DNS
- RFC 1982 — Serial Number Arithmetic
- RFC 1876 — A Means for Expressing Location Information in the Domain Name System
- RFC 1348 — DNS NSAP RRs
- RFC 1183 — New DNS RR Definitions
- RFC 1101 — DNS encoding of network names and other types
Text
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