Algorithms for synchronizing network clocks
RFC 956, “Algorithms for synchronizing network clocks”, is an Unknown document published in September 1985 by D.L. Mills. The canonical text is published by the RFC Editor.
Abstract
This RFC discussed clock synchronization algorithms for the ARPA-Internet community, and requests discussion and suggestions for improvements. The recent interest within the Internet community in determining accurate time from a set of mutually suspicious network clocks has been prompted by several occasions in which errors were found in usually reliable, accurate clock servers after thunderstorms which disrupted their power supply. To these sources of error should be added those due to malfunctioning hardware, defective software and operator mistakes, as well as random errors in the mechanism used to set and synchronize clocks. This report suggests a stochastic model and algorithms for computing a good estimator from time-offset samples measured between clocks connected via network links. Included in this report are descriptions of certain experiments which give an indication of the effectiveness of the algorithms.
What “Unknown” means
The standards-track status of this early RFC was never formally classified.
The canonical text of RFC 956 is hosted at rfc-editor.org. Available in TXT,HTML.
- RFC 955 Towards a transport service for transaction processing applications
- RFC 957 Experiments in network clock synchronization
- RFC 954 NICNAME/WHOIS
- RFC 958 Network Time Protocol
- RFC 953 Hostname Server
- RFC 959 File Transfer Protocol
- RFC 952 DoD Internet host table specification
- RFC 960 Assigned numbers