Home

Ntp Workgroup RFCs

Browse Ntp Workgroup RFCs by Number

RFC5905 - Network Time Protocol Version 4: Protocol and Algorithms Specification
The Network Time Protocol (NTP) is widely used to synchronize computer clocks in the Internet. This document describes NTP version 4 (NTPv4), which is backwards compatible with NTP version 3 (NTPv3), described in RFC 1305, as well as previous versions of the protocol. NTPv4 includes a modified protocol header to accommodate the Internet Protocol version 6 address family. NTPv4 includes fundamental improvements in the mitigation and discipline algorithms that extend the potential accuracy to the tens of microseconds with modern workstations and fast LANs. It includes a dynamic server discovery scheme, so that in many cases, specific server configuration is not required. It corrects certain errors in the NTPv3 design and implementation and includes an optional extension mechanism. [STANDARDS-TRACK]
RFC5906 - Network Time Protocol Version 4: Autokey Specification
This memo describes the Autokey security model for authenticating servers to clients using the Network Time Protocol (NTP) and public key cryptography. Its design is based on the premise that IPsec schemes cannot be adopted intact, since that would preclude stateless servers and severely compromise timekeeping accuracy. In addition, Public Key Infrastructure (PKI) schemes presume authenticated time values are always available to enforce certificate lifetimes; however, cryptographically verified timestamps require interaction between the timekeeping and authentication functions.
This memo includes the Autokey requirements analysis, design principles, and protocol specification. A detailed description of the protocol states, events, and transition functions is included. A prototype of the Autokey design based on this memo has been implemented, tested, and documented in the NTP version 4 (NTPv4) software distribution for the Unix, Windows, and Virtual Memory System (VMS) operating systems at http://www.ntp.org. This document is not an Internet Standards Track specification; it is published for informational purposes.
RFC5907 - Definitions of Managed Objects for Network Time Protocol Version 4 (NTPv4)
The Network Time Protocol (NTP) is used in networks of all types and sizes for time synchronization of servers, workstations, and other networked equipment. As time synchronization is more and more a mission-critical service, standardized means for monitoring and management of this subsystem of a networked host are required to allow operators of such a service to set up a monitoring system that is platform- and vendor-independent. This document provides a standardized collection of data objects for monitoring the NTP entity of such a network participant and it is part of the NTP version 4 standardization effort. [STANDARDS-TRACK]
RFC5908 - Network Time Protocol (NTP) Server Option for DHCPv6
The NTP Server Option for Dynamic Host Configuration Protocol for IPv6 (DHCPv6) provides NTPv4 (Network Time Protocol version 4) server location information to DHCPv6 hosts. [STANDARDS-TRACK]
RFC7821 - UDP Checksum Complement in the Network Time Protocol (NTP)
The Network Time Protocol (NTP) allows clients to synchronize to a time server using timestamped protocol messages. To facilitate accurate timestamping, some implementations use hardware-based timestamping engines that integrate the accurate transmission time into every outgoing NTP packet during transmission. Since these packets are transported over UDP, the UDP Checksum field is then updated to reflect this modification. This document proposes an extension field that includes a 2-octet Checksum Complement, allowing timestamping engines to reflect the checksum modification in the last 2 octets of the packet rather than in the UDP Checksum field. The behavior defined in this document is interoperable with existing NTP implementations.
RFC7822 - Network Time Protocol Version 4 (NTPv4) Extension Fields
The Network Time Protocol version 4 (NTPv4) defines the optional usage of extension fields. An extension field, as defined in RFC 5905, is an optional field that resides at the end of the NTP header and that can be used to add optional capabilities or additional information that is not conveyed in the standard NTP header. This document updates RFC 5905 by clarifying some points regarding NTP extension fields and their usage with Message Authentication Codes (MACs).