Simple Network Time Protocol (SNTP) Version 4 for IPv4, IPv6 and OSI (RFC2030)
Original Publication Date: 1996-Oct-01
Included in the Prior Art Database: 2019-Feb-16
Internet Society Requests For Comment (RFCs)
This memorandum describes the Simple Network Time Protocol (SNTP) Version 4, which is an adaptation of the Network Time Protocol (NTP) used to synchronize computer clocks in the Internet. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.
Network Working Group D. Mills Request for Comments: 2030 University of Delaware Obsoletes: 1769 October 1996 Category: Informational
Simple Network Time Protocol (SNTP) Version 4 for IPv4, IPv6 and OSI
Status of this Memo
This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
This memorandum describes the Simple Network Time Protocol (SNTP) Version 4, which is an adaptation of the Network Time Protocol (NTP) used to synchronize computer clocks in the Internet. SNTP can be used when the ultimate performance of the full NTP implementation described in RFC-1305 is not needed or justified. When operating with current and previous NTP and SNTP versions, SNTP Version 4 involves no changes to the NTP specification or known implementations, but rather a clarification of certain design features of NTP which 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.
The only significant protocol change in SNTP Version 4 over previous versions of NTP and SNTP is a modified header interpretation to accommodate Internet Protocol Version 6 (IPv6) [DEE96] and OSI [COL94] addressing. However, SNTP Version 4 includes certain optional extensions to the basic Version 3 model, including an anycast mode and an authentication scheme designed specifically for multicast and anycast modes. While the anycast mode extension is described in this document, the authentication scheme extension will be described in another document to be published later. Until such time that a definitive specification is published, these extensions should be considered provisional.
This memorandum obsoletes RFC-1769, which describes SNTP Version 3. Its purpose is to correct certain inconsistencies in the previous document and to clarify header formats and protocol operations for current NTP Version 3 (IPv4) and proposed NTP Version 4 (IPv6 and OSI), which are also used for SNTP. A working knowledge of the NTP Version 3 specification RFC-1305 is not required for an implementation of SNTP.
Mills Informational [Page 1]
RFC 2030 SNTPv4 for IPv4, IPv6 and OSI October 1996
The Network Time Protocol (NTP) Version 3 specified in RFC-1305 [MIL92] is widely used to synchronize computer clocks in the global Internet. It provides comprehensive mechanisms to access national time and frequency dissemination services, organize the time- synchronization subnet and adjust the local clock in each participating subnet peer. In most places of the Internet of today, NTP provides accuracies of 1-50 ms, depending on the characteristics of the synchronization source and network paths.
RFC-1305 specifies the NTP Version 3 protocol machine in terms of events, states, transition functions and actions and, in addition, engineered algorithms to improve the timekeeping quality and m...