Network Time Security
draft-ietf-ntp-network-time-security-06
NTP Working Group D. Sibold
Internet-Draft PTB
Intended status: Standards Track S. Roettger
Expires: July 20, 2015 Google Inc.
K. Teichel
PTB
January 16, 2015
Network Time Security
draft-ietf-ntp-network-time-security-06.txt
Abstract
This document describes Network Time Security (NTS), a collection of
measures that enable secure time synchronization with time servers
using protocols like the Network Time Protocol (NTP) or the Precision
Time Protocol (PTP). Its design considers the special requirements
of precise timekeeping which are described in Security Requirements
of Time Protocols in Packet Switched Networks [RFC7384].
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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."
This Internet-Draft will expire on July 20, 2015.
Sibold, et al. Expires July 20, 2015 [Page 1]
Internet-Draft NTS January 2015
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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 . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Security Threats . . . . . . . . . . . . . . . . . . . . . . 4
3. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Terms and Abbreviations . . . . . . . . . . . . . . . . . . . 4
5. NTS Overview . . . . . . . . . . . . . . . . . . . . . . . . 4
6. Protocol Messages . . . . . . . . . . . . . . . . . . . . . . 5
6.1. Association Messages . . . . . . . . . . . . . . . . . . 6
6.1.1. Message Type: "client_assoc" . . . . . . . . . . . . 6
6.1.2. Message Type: "server_assoc" . . . . . . . . . . . . 6
6.2. Cookie Messages . . . . . . . . . . . . . . . . . . . . . 7
6.2.1. Message Type: "client_cook" . . . . . . . . . . . . . 7
6.2.2. Message Type: "server_cook" . . . . . . . . . . . . . 7
6.3. Unicast Time Synchronisation Messages . . . . . . . . . . 8
6.3.1. Message Type: "time_request" . . . . . . . . . . . . 8
6.3.2. Message Type: "time_response" . . . . . . . . . . . . 8
6.4. Broadcast Parameter Messages . . . . . . . . . . . . . . 9
6.4.1. Message Type: "client_bpar" . . . . . . . . . . . . . 9
6.4.2. Message Type: "server_bpar" . . . . . . . . . . . . . 9
6.5. Broadcast Messages . . . . . . . . . . . . . . . . . . . 10
6.5.1. Message Type: "server_broad" . . . . . . . . . . . . 10
6.6. Broadcast Key Check . . . . . . . . . . . . . . . . . . . 10
6.6.1. Message Type: "client_keycheck" . . . . . . . . . . . 10
6.6.2. Message Type: "server_keycheck" . . . . . . . . . . . 11
7. Message Dependencies . . . . . . . . . . . . . . . . . . . . 11
8. Server Seed Considerations . . . . . . . . . . . . . . . . . 12
9. Hash Algorithms and MAC Generation . . . . . . . . . . . . . 13
9.1. Hash Algorithms . . . . . . . . . . . . . . . . . . . . . 13
9.2. MAC Calculation . . . . . . . . . . . . . . . . . . . . . 13
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
11. Security Considerations . . . . . . . . . . . . . . . . . . . 13
Show full document text