RFC 7720

DNS Root Name Service Protocol and Deployment Requirements

📅 published December 2015, from ietf

DNS Root Name Service Protocol and Deployment Requirements 🎀

okay bestie, here's the title block tea ☕✨

RFC number: 7720, also BCP 40 (it's a Best Current Practice 👑)
Authors: Marc Blanchet (Viagenie) and Lars-Johan Liman (Netnod) 💖
Date: December 2015 📅
ISSN: 2070-1721
Obsoletes: RFC 2870 💅 (so this one replaces it, and it's not updating anything)

Abstract 🌸

the DNS root name service is literally a critical part of how the Internet works 😭 this doc defines the protocol and deployment requirements for it. operational requirements are out of scope, so we're not talking about those here 🙈

Status of This Memo ✨

this memo documents an Internet Best Current Practice 🫶

this is a product of the Internet Engineering Task Force (IETF). it represents the consensus of the IETF community, it got public review, and the Internet Engineering Steering Group (IESG) approved it for publication. more info on BCPs is in Section 2 of RFC 5741 🦋

for the current status, any errata, and how to give feedback, check http://www.rfc-editor.org/info/rfc7720 💜

Copyright Notice 🌈

this document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) as they stood on the publication date. please actually read these, because they spell out your rights and restrictions for this document 🙏 any Code Components pulled from this document have to include Simplified BSD License text, as described in Section 4.e of the Trust Legal Provisions, and they come without warranty, as described in that license 💀

Table of Contents 🧚

1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
  1.1.  Relationship to RFC 2870  . . . . . . . . . . . . . . . .   2
2.  Protocol Requirements . . . . . . . . . . . . . . . . . . . .   3
3.  Deployment Requirements . . . . . . . . . . . . . . . . . . .   3
4.  Security Considerations . . . . . . . . . . . . . . . . . . .   3
5.  Informative References  . . . . . . . . . . . . . . . . . . .   4
Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .   5
Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   6

1. Introduction 💖

okay so [RFC2870] is the doc that talks about both protocol AND operational requirements for root name servers for the DNS protocol [RFC1035] 📖 but things have evolved since then, so it makes way more sense to split those two sets of requirements into two separate docs ✨ this one only defines the protocol requirements and some deployment requirements. the operational requirements from RFC 2870 got removed, and now the Root Server System Advisory Committee of ICANN defines them, and they're written up in [RSSAC-001] 🫶

the root servers are authoritative servers for the unique [RFC2826] root zone (".") [ROOTZONE] 👑 they also serve the root-servers.net zone right now, and some of them serve the zone for the .arpa top-level domain [ARPAZONE] [RFC3172] 🦋 this doc describes the external interface of the root name servers from a protocol point of view. it lays out the basic requirements DNS clients need to meet when they talk to a root name service over the public Internet 🌸

the keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD, SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL, when they show up in this document, are to be read as described in BCP 14, [RFC2119]. these words are the ones with the real weight, so pay attention to them 🔥

1.1. Relationship to RFC 2870 🧚

this document obsoletes [RFC2870] 💅

this document and [RSSAC-001] together functionally replace [RFC2870] ✨

2. Protocol Requirements 🎀

this section describes the minimum high-level protocol requirements. the operative details live in [RSSAC-001] 💜

the root name service:

MUST implement core DNS [RFC1035] and clarifications to the DNS [RFC2181]. 🌈
MUST support IPv4 [RFC791] and IPv6 [RFC2460] transport of DNS queries and responses. 🦋
MUST support UDP [RFC768] and TCP [RFC793] transport of DNS queries and responses. 💖
MUST generate checksums when sending UDP datagrams, and MUST verify checksums when receiving UDP datagrams that contain a non-zero checksum. 🙈
MUST implement DNSSEC [RFC4035] as an authoritative name service. 🔥
MUST implement extension mechanisms for DNS (EDNS(0)) [RFC6891]. ⭐

3. Deployment Requirements 🍓

the root name service:

MUST answer queries from any entity conforming to [RFC1122] with a valid IP address. 🫶
MUST serve the unique [RFC2826] root zone [ROOTZONE]. 👑

4. Security Considerations 💀

this document does not specify a new protocol. however, the root name service is a key component of the Internet architecture, and it plays a key role in the overall security of the Internet [RFC2826] 😭 the specific security considerations for the DNS protocols are discussed in their own specifications. the security considerations on the operational side of the root name servers are discussed in [RSSAC-001]. this part matters a LOT, so don't skip it 🚨

5. Informative References 📚

these are the references, all of them, bestie 💜

[ARPAZONE]  IANA, ".ARPA Zone Management",
            <http://www.iana.org/domains/arpa>.

[RFC768]    Postel, J., "User Datagram Protocol", STD 6, RFC 768,
            DOI 10.17487/RFC0768, August 1980,
            <http://www.rfc-editor.org/info/rfc768>.

[RFC791]    Postel, J., "Internet Protocol", STD 5, RFC 791,
            DOI 10.17487/RFC0791, September 1981,
            <http://www.rfc-editor.org/info/rfc791>.

[RFC793]    Postel, J., "Transmission Control Protocol", STD 7,
            RFC 793, DOI 10.17487/RFC0793, September 1981,
            <http://www.rfc-editor.org/info/rfc793>.

[RFC1035]   Mockapetris, P., "Domain names - implementation and
            specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
            November 1987, <http://www.rfc-editor.org/info/rfc1035>.

[RFC1122]   Braden, R., Ed., "Requirements for Internet Hosts -
            Communication Layers", STD 3, RFC 1122,
            DOI 10.17487/RFC1122, October 1989,
            <http://www.rfc-editor.org/info/rfc1122>.

[RFC2119]   Bradner, S., "Key words for use in RFCs to Indicate
            Requirement Levels", BCP 14, RFC 2119,
            DOI 10.17487/RFC2119, March 1997,
            <http://www.rfc-editor.org/info/rfc2119>.

[RFC2181]   Elz, R. and R. Bush, "Clarifications to the DNS
            Specification", RFC 2181, DOI 10.17487/RFC2181, July
            1997, <http://www.rfc-editor.org/info/rfc2181>.

[RFC2460]   Deering, S. and R. Hinden, "Internet Protocol, Version 6
            (IPv6) Specification", RFC 2460, DOI 10.17487/RFC2460,
            December 1998, <http://www.rfc-editor.org/info/rfc2460>.

[RFC2826]   Internet Architecture Board, "IAB Technical Comment on
            the Unique DNS Root", RFC 2826, DOI 10.17487/RFC2826, May
            2000, <http://www.rfc-editor.org/info/rfc2826>.

[RFC2870]   Bush, R., Karrenberg, D., Kosters, M., and R. Plzak,
            "Root Name Server Operational Requirements", BCP 40,
            RFC 2870, DOI 10.17487/RFC2870, June 2000,
            <http://www.rfc-editor.org/info/rfc2870>.

[RFC3172]   Huston, G., Ed., "Management Guidelines & Operational
            Requirements for the Address and Routing Parameter Area
            Domain ("arpa")", BCP 52, RFC 3172, DOI 10.17487/RFC3172,
            September 2001, <http://www.rfc-editor.org/info/rfc3172>.

[RFC4035]   Arends, R., Austein, R., Larson, M., Massey, D., and S.
            Rose, "Protocol Modifications for the DNS Security
            Extensions", RFC 4035, DOI 10.17487/RFC4035, March 2005,
            <http://www.rfc-editor.org/info/rfc4035>.

[RFC6891]   Damas, J., Graff, M., and P. Vixie, "Extension Mechanisms
            for DNS (EDNS(0))", STD 75, RFC 6891,
            DOI 10.17487/RFC6891, April 2013,
            <http://www.rfc-editor.org/info/rfc6891>.

[ROOTZONE]  "Root Zone", <ftp://rs.internic.net/domain/root.zone>.

[RSSAC-001] Root Server System Advisory Committee (RSSAC), "Service
            Expectations of Root Servers", November 2014,
            <https://www.icann.org/en/system/files/files/
            rssac-001-root-service-expectations-04dec15-en.pdf>.

Acknowledgements 🫶

some text was taken from [RFC2870] 🌷 the editors would like to sincerely thank the following people for their valuable contributions to the text: Andrew Sullivan, Simon Perreault, Jean-Philippe Dionne, Dave Thaler, Russ Housley, Alissa Cooper, Joe Abley, Joao Damas, Daniel Karrenberg, Jacques Latour, Eliot Lear, Bill Manning, David Conrad, Paul Hoffman, Terry Manderson, Jari Arkko, and Mark Andrews. iconic cast 👑💖

Authors' Addresses 🧚

Marc Blanchet
Viagenie
246 Aberdeen
Quebec, QC  G1R 2E1
Canada

Email: Marc.Blanchet@viagenie.ca
URI:   http://viagenie.ca


Lars-Johan Liman
Netnod Internet Exchange
Box 30194
SE-104 25 Stockholm
Sweden

Email: liman@netnod.se
URI:   http://www.netnod.se/

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ietf: rfc7720 2015-12
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