RFC 4330 · INFORMATIONAL · 2006

Simple Network Time Protocol Version 4 for IPv4, IPv6 and OSI

Overview

RFC 4330, “Simple Network Time Protocol Version 4 for IPv4, IPv6 and OSI”, is an Informational document published in January 2006 by D. Mills. It obsoletes RFC 1769, RFC 2030. It has been obsoleted by RFC 5905 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

This memorandum describes the Simple Network Time Protocol Version 4 (SNTPv4), which is a subset of the Network Time Protocol (NTP) used to synchronize computer clocks in the Internet. SNTPv4 can be used when the ultimate performance of a full NTP implementation based on RFC 1305 is neither needed nor justified. When operating with current and previous NTP and SNTP versions, SNTPv4 requires no changes to the specifications or known implementations, but rather clarifies certain design features that allow operation in a simple, stateless remote-procedure call (RPC) mode with accuracy and reliability expectations similar to the UDP/TIME protocol described in RFC 868.

This memorandum obsoletes RFC 1769, which describes SNTP Version 3 (SNTPv3), and RFC 2030, which describes SNTPv4. Its purpose is to correct certain inconsistencies in the previous documents and to clarify header formats and protocol operations for NTPv3 (IPv4) and SNTPv4 (IPv4, IPv6, and OSI), which are also used for SNTP. A further purpose is to provide guidance for home and business client implementations for routers and other consumer devices to protect the server population from abuse. A working knowledge of the NTPv3 specification, RFC 1305, is not required for an implementation of SNTP. This memo provides information for the Internet community.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 4330 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 1769 RFC 2030
Obsoleted by
RFC 5905
Other RFCs from 2006

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