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                                                             Network Time Security (NTS)

   Created
   2020-04-07

   Last Updated
   2026-06-02

   Available Formats
   [IMG]
   XML [IMG]
   HTML [IMG]
   Plain text

   Registries Included Below

     • Network Time Security Key Establishment Record Types
     • Network Time Security Next Protocols
     • Network Time Security Error Codes
     • Network Time Security Warning Codes

Network Time Security Key Establishment Record Types

   Expert(s)

 Miroslav Lichvar, Daniel Franke

   Reference
   [RFC8915]

   Available Formats
   [IMG]
   CSV

      Range      Registration Procedures
   0-1023      IETF Review
   1024-16383  Specification Required
   16384-32767 Private or Experimental Use

   Record Type Number                          Description                                                     Reference
   0                  End of Message                                                [RFC8915, Section 4.1.1]
   1                  NTS Next Protocol Negotiation                                 [RFC8915, Section 4.1.2]
   2                  Error                                                         [RFC8915, Section 4.1.3]
   3                  Warning                                                       [RFC8915, Section 4.1.4]
   4                  AEAD Algorithm Negotiation                                    [RFC8915, Section 4.1.5]
   5                  New Cookie for NTPv4                                          [RFC8915, Section 4.1.6]
   6                  NTPv4 Server Negotiation                                      [RFC8915, Section 4.1.7]
   7                  NTPv4 Port Negotiation                                        [RFC8915, Section 4.1.8]
   8                  Keep Alive (TEMPORARY - registered 2026-06-02, expires        [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.1]
                      2027-06-02)
   9                  Supported Next Protocol List (TEMPORARY - registered          [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.2]
                      2026-06-02, expires 2027-06-02)
   10                 Supported Algorithm List (TEMPORARY - registered 2026-06-02,  [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.3]
                      expires 2027-06-02)
   11                 List Server Names (TEMPORARY - registered 2026-06-02, expires [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.4]
                      2027-06-02)
   12                 Fixed Key Request (TEMPORARY - registered 2026-06-02, expires [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.5]
                      2027-06-02)
   13                 NTP Server Deny (TEMPORARY - registered 2026-06-02, expires   [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.6]
                      2027-06-02)
   14                 Authentication Token (TEMPORARY - registered 2026-06-02,      [draft-ietf-ntp-nts-keyexchange-pool-00, Section 6.7]
                      expires 2027-06-02)
   15-1023            Unassigned
   1024               Compliant AES-128-GCM-SIV Exporter Context                    [https://chrony-project.org/doc/spec/nts-compliant-128gcm.html]
   1025-16383         Unassigned
   16384-32767        Reserved for Private or Experimental Use                      [RFC8915]

Network Time Security Next Protocols

   Expert(s)

 Miroslav Lichvar, Daniel Franke

   Reference
   [RFC8915]

   Available Formats
   [IMG]
   CSV

      Range      Registration Procedures
   0-1023      IETF Review
   1024-32767  Specification Required
   32768-65535 Private or Experimental Use

   Protocol ID              Protocol Name               Reference
   0           Network Time Protocol version 4 (NTPv4)  [RFC8915]
   1-32767     Unassigned
   32768-65535 Reserved for Private or Experimental Use [RFC8915]

Network Time Security Error Codes

   Expert(s)

 Miroslav Lichvar, Daniel Franke

   Reference
   [RFC8915]

   Available Formats
   [IMG]
   CSV

      Range      Registration Procedures
   0-1023      IETF Review
   1024-32767  Specification Required
   32768-65535 Private or Experimental Use

     Number                  Description                       Reference
   0           Unrecognized Critical Record             [RFC8915, Section 4.1.3]
   1           Bad Request                              [RFC8915, Section 4.1.3]
   2           Internal Server Error                    [RFC8915, Section 4.1.3]
   3-32767     Unassigned
   32768-65535 Reserved for Private or Experimental Use [RFC8915]

Network Time Security Warning Codes

   Expert(s)

 Miroslav Lichvar, Daniel Franke

   Reference
   [RFC8915]

   Available Formats
   [IMG]
   CSV

      Range      Registration Procedures
   0-1023      IETF Review
   1024-32767  Specification Required
   32768-65535 Private or Experimental Use

     Number                  Description                Reference
   0-32767     Unassigned
   32768-65535 Reserved for Private or Experimental Use [RFC8915]

   Licensing Terms