The Network Time Protocol Version 4 (NTPv4) Extension Fields
draft-ietf-ntp-extension-field-06

The information below is for an old version of the document
Document Type Active Internet-Draft (ntp WG)
Last updated 2016-02-04 (latest revision 2015-11-26)
Stream IETF
Intended RFC status Proposed Standard
Formats pdf htmlized bibtex
Reviews
Stream WG state Submitted to IESG for Publication
Document shepherd Karen O'Donoghue
Shepherd write-up Show (last changed 2015-08-13)
IESG IESG state Approved-announcement to be sent::Revised I-D Needed
Consensus Boilerplate Yes
Telechat date
Responsible AD Brian Haberman
Send notices to (None)
IANA IANA review state IANA OK - No Actions Needed
NTP Working Group                                             T. Mizrahi
Internet Draft                                                   Marvell
Intended status: Standards Track                                D. Mayer
Updates: 5905                                    Network Time Foundation
Expires: May 2016                                      November 26, 2015

       The Network Time Protocol Version 4 (NTPv4) Extension Fields
                   draft-ietf-ntp-extension-field-06.txt

Abstract

   The Network Time Protocol Version 4 (NTPv4) defines the optional
   usage of extension fields. An extension field, defined in RFC5905, is
   an optional field that resides at the end of the NTP header, and can
   be used to add optional capabilities or additional information that
   is not conveyed in the standard NTP header. This document updates
   RFC5905 by clarifying some points regarding NTP extension fields and
   their usage with Message Authentication Codes (MAC).

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on May 26, 2016.

Copyright Notice

   Copyright (c) 2015 IETF Trust and the persons identified as the
   document authors. All rights reserved.

Mizrahi, Mayer           Expires May 26, 2016                  [Page 1]
Internet-Draft           NTP Extension Field              November 2015

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document. Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1. Introduction...................................................2
   2. Conventions Used in this Document..............................3
      2.1. Terminology...............................................3
      2.2. Terms & Abbreviations.....................................3
   3. NTP Extension Fields - RFC 5905 Update.........................3
   4. Security Considerations........................................6
   5. IANA Considerations............................................7
   6. Acknowledgments................................................7
   7. References.....................................................7
      7.1. Normative References......................................7
      7.2. Informative References....................................7

1. Introduction

   The NTP header format consists of a set of fixed fields that may be
   followed by some optional fields. Two types of optional fields are
   defined, Message Authentication Codes (MAC), and extension fields, as
   defined in Section 7.5 of [RFC5905].

   If a MAC is used, it resides at the end of the packet. This field can
   be either 24 octets long, 20 octets long, or a 4-octet crypto-NAK.

   NTP extension fields were defined in [RFC5905] as a generic mechanism
   that allows to add future extensions and features without modifying
   the NTP header format (Section 16 of [RFC5905]).

   The only currently defined extension fields are the ones used by the
   AutoKey protocol [RFC5906], and the Checksum Complement [NTPComp].
   The AutoKey extension field is always followed by a MAC, and Section
   10 of [RFC5906] specifies the parsing rules that allow a host to
   distinguish between an extension field and a MAC. However, a MAC is
   not mandatory after an extension field; an NTPv4 packet can include
   one or more extension fields without including a MAC (Section 7.5 of
   [RFC5905]).

Mizrahi, Mayer           Expires May 26, 2016                  [Page 2]
Internet-Draft           NTP Extension Field              November 2015

   This document updates [RFC5905] by clarifying some points regarding
   the usage of extension fields. Specifically, this document updates
Show full document text