Network Time Protocol Best Current Practices

Metadata

Publisher: IETF
Doc Type: Best Practice
Pages: 26
Abstract: The Network Time Protocol (NTP) is one of the oldest protocols on the Internet and has been widely used since its initial publication. This document is a collection of best practices for the general operation of NTP servers and clients on the Internet. It includes recommendations for the stable, accurate, and secure operation of NTP infrastructure. This document is targeted at NTP version 4 as described in RFC 5905.
Publication Date: 2019-07-01
Status Note: Best Current Practice
DOI: 10.17487/RFC8633
Link: https://doi.org/10.17487/RFC8633
Author(s): Denis Reilly
Harlan Stenn
Dieter Sibold
Keyword(s): NTP

Latest version of IETF RFC 8633

Document Versions — IETF RFC 8633

▶ IETF RFC 8633 (2019-07-01)

THIS DOC [ACTIVE] [LATEST VERSION]

Normative Reference(s)

IETF RFC 2119 [Active*]
IETF RFC 2827 [Active*]
IETF RFC 4085 [Active*]
IETF RFC 4786 [Active*]
IETF RFC 5905 [Active*]
IETF RFC 8174 [Active*]

Bibliographic Reference(s)

10.1145-2663716.2663717 — IMC14 EXTERNAL
10.1145-2935634.2935637 — CCR16 EXTERNAL
10.14722-ndss.2014.23233 — NDSS14 EXTERNAL
10.14722-ndss.2016.23090 — NDSS16 EXTERNAL
IETF.draft-ietf-ntp-data-minimization-04 — DATAMIN EXTERNAL
IETF.draft-ietf-ntp-mode-6-cmds-06 — CTRLMSG EXTERNAL
IETF.draft-ietf-ntp-using-nts-for-ntp-20 — NTSFORNTP EXTERNAL
Wikipedia, "Solar Time", May 2019, < https://en.wikipedia.org/w/index.php? title=Solar_time&oldid=896601472#Mean_solar_time >. EXTERNAL
Mills, D., "Computer network time synchronization: the Network Time Protocol", CRC Press, 2006. EXTERNAL
IERS, "IERS Bulletins", < https://www.iers.org/IERS/EN/Publications/Bulletins/ bulletins.html >. EXTERNAL
Van Gundy, M., "Network Time Protocol ntpq and ntpdc Origin Timestamp Disclosure Vulnerability", January 2016, < https://www.talosintel.com/reports/TALOS-2016-0078 >. EXTERNAL
NTP Pool Project, "The NTP Pool for Vendors", < https://www.pool.ntp.org/en/vendors.html >. EXTERNAL
Prince, M., "Technical Details Behind a 400Gbps NTP Amplification DDoS Attack", February 2014, < https://blog.cloudflare.com/technical-details-behind-a- 400gbps-ntp-amplification-ddos-attack >. EXTERNAL
Roettger, S., "Autokey-Protocol Analysis", August 2011, < https://lists.ntp.org/pipermail/ ntpwg/2011-August/001714.html >. EXTERNAL
Burnicki, M., "Leap Second Smearing", < http://bk1.ntp.org/ ntp-stable/README.leapsmear?PAGE=anno >. EXTERNAL
Network Time Foundation, "Configuring NTP", November 2018, < https://support.ntp.org/bin/view/Support/ConfiguringNTP >. EXTERNAL
Van Gundy, M. and J. Gardner, "Network Time Protocol Origin Timestamp Check Impersonation Vulnerability", January 2016, < https://www.talosintel.com/reports/TALOS-2016-0077 >. EXTERNAL
Network Time Foundation, "NTP Software Downloads", < http://www.ntp.org/downloads.html >. EXTERNAL
" BCP38 .info Wiki", October 2016, < http://www.bcp38.info >. EXTERNAL
NTP Pool Project, "Use the Pool", < https://www.pool.ntp.org/en/use.html >. EXTERNAL
Wikipedia, "NTP Server Misuse and Abuse", May 2019, < https://en.wikipedia.org/w/index.php? title=NTP_server_misuse_and_abuse&oldid=899024751 >. EXTERNAL
Gardner, J. and M. Lichvar, "Xleave Pivot: NTP Basic Mode to Interleaved", April 2016, < https://blog.talosintel.com/2016/04/ vulnerability-spotlight-further-ntpd_27.html >. EXTERNAL
IETF RFC 1305 [Superseded*]
IETF RFC 5906 [Active*]
IETF RFC 6151 [Active*]
IETF RFC 7094 [Active*]
IETF RFC 7384 [Active*]
IETF RFC 8573 [Active*]

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Referenced By

IETF RFC 9145 [Active*]
IETF RFC 9182 [Active*]