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Network Time Protocol (NTP) over the OSI Remote Operations Service (RFC1165)

IP.com Disclosure Number: IPCOM000001977D
Original Publication Date: 1990-Jun-01
Included in the Prior Art Database: 2019-Feb-11
Document File: 10 page(s) / 12K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

J. Crowcroft: AUTHOR [+1]

Related Documents

10.17487/RFC1165: DOI

Abstract

This memo suggests an Experimental Protocol for the OSI and Internet communities. Hosts in either community, and in particular those on both are encouraged to experiment with this mechanism.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 21% of the total text.

Network Working Group J. Crowcroft Request for Comments: 1165 UCL J. Onions Nottingham University June 1990

Network Time Protocol (NTP) over the OSI Remote Operations Service

Status of this Memo

This memo suggests an Experimental Protocol for the OSI and Internet communities. Hosts in either community, and in particular those on both are encouraged to experiment with this mechanism. Please refer to the current edition of the "IAB Official Protocol Standards" for the standardization state and status of this protocol. Distribution of this memo is unlimited.

Table of Contents

1. Introduction........................................... 1 1.1 Motivation............................................ 1 2. Protocol Overview...................................... 2 3. Operation of the Protocol.............................. 3 4. Network Considerations................................. 4 5. Implementation Model................................... 4 6. Constructing NTP Data Fields........................... 4 7. Discussion............................................. 4 8. Prototype Experience................................... 5 9. References............................................. 5 10. Acknowledgements...................................... 6 Appendix A. NTP Remote Operations Service Specification... 6 11. Security Considerations............................... 9 12. Authors’ Addresses.................................... 9

1. Introduction

This document describes the Remote Operations and Abstract Syntax for the operation of the Network Time Protocol (NTP) over an ISO OSI stack.

NTP itself is documented in great detail in RFC 1119.

1.1 Motivation

The motivation behind the implementation of a Remote Operations

Crowcroft & Onions [Page 1]

RFC 1165 NTP over OSI June 1990

Service implementation of NTP is fourfold.

1. The inclusion of a useful service to an OSI environment.

2. The feasibility of automatically checking a ROS/ASN.1 specification, and automatically generating code to implement the protocol.

3. The feasibility of running NTP on connection oriented network services (CONS or X.25), and consequentially, the ability to use connection success or failure to optimise reachability discovery.

4. The generalisation of the last point: the use of ROS makes NTP independent of the underlying communications architecture.

The need for time synchronisation is clear, and RFC 1119 indicates a few of the necessary uses of this service. However, it is becoming clear that OSI applications are very much in need of this service too. Not just in the local context but across the wide area. For example much of the strong authentication outlined in X.511 is based on encrypted packets with time stamps to indicate how long the packet is valid for. If two hosts have clocks that are not closely synchronised, the host with the faster clock will be more prone to cryptographic attacks from the slower, and the slower host will possibly find it is unauthentable.

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