Network Working Group N. Wu
Internet-Draft Huawei
Intended status: Standards Track A. Kumar S N
Expires: September 6, 2018 RtBrick Inc.
Y. Zhao
Ericsson
D. Dhody
Huawei
A. Sinha
RtBrick Inc.
March 5, 2018
A YANG Data Model for NTP
draft-ietf-ntp-yang-data-model-02
Abstract
This document defines a YANG data model for Network Time Protocol
(NTP) implementations. The data model includes configuration data
and state data.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
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 https://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 September 6, 2018.
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Copyright Notice
Copyright (c) 2018 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
(https://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
1.1. Operational State . . . . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
2. NTP data model . . . . . . . . . . . . . . . . . . . . . . . 3
3. Relationship with NTPv4-MIB . . . . . . . . . . . . . . . . . 6
4. Relationship with RFC 7317 . . . . . . . . . . . . . . . . . 7
5. NTP YANG Module . . . . . . . . . . . . . . . . . . . . . . . 8
6. Usage Example . . . . . . . . . . . . . . . . . . . . . . . . 28
6.1. Unicast association . . . . . . . . . . . . . . . . . . . 28
6.2. Refclock master . . . . . . . . . . . . . . . . . . . . . 29
6.3. Authentication configuration . . . . . . . . . . . . . . 30
6.4. Access configuration . . . . . . . . . . . . . . . . . . 32
6.5. Multicast configuration . . . . . . . . . . . . . . . . . 32
6.6. Manycast configuration . . . . . . . . . . . . . . . . . 36
6.7. Clock state . . . . . . . . . . . . . . . . . . . . . . . 39
6.8. Get all association . . . . . . . . . . . . . . . . . . . 39
6.9. Global statistic . . . . . . . . . . . . . . . . . . . . 41
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41
8. Security Considerations . . . . . . . . . . . . . . . . . . . 42
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 43
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 43
10.1. Normative References . . . . . . . . . . . . . . . . . . 43
10.2. Informative References . . . . . . . . . . . . . . . . . 44
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 44
1. Introduction
This document defines a YANG [RFC6020] data model for Network Time
Protocol [RFC5905] implementations.
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The data model convers configuration of system parameters of NTP,
such as access rules, authentication and VPN Routing and Forwarding
(VRF) binding, and also associations of NTP in different modes and
parameters of per-interface. It also provides information about
running state of NTP implementations.
1.1. Operational State
NTP Operational State is included in the same tree as NTP
configuration, consistent with Network Management Datastore
Architecture [I-D.ietf-netmod-revised-datastores]. NTP current state
and statistics are also maintained in the operational state.
Additionally, the operational state also include the associations
state.
1.2. Terminology
The terminology used in this document is aligned to [RFC5905].
1.3. Tree Diagrams
A simplified graphical representation of the data model is used in
this document. This document uses the graphical representation of
data models defined in [I-D.ietf-netmod-yang-tree-diagrams].
2. NTP data model
This document defines the YANG module "ietf-ntp", which has the
following structure:
module: ietf-ntp
+--rw ntp!
+--rw port? uint16 {ntp-port}?
+--rw refclock-master!
| +--rw master-stratum? ntp-stratum
+--rw authentication
| +--rw auth-enabled? boolean
| +--rw trusted-keys* [key-id]
| | +--rw key-id leafref
| +--rw authentication-keys* [key-id]
| +--rw key-id uint32
| +--rw algorithm? identityref
| +--rw password? ianach:crypt-hash
+--rw access-rules
| +--rw access-rule* [access-mode]
| +--rw access-mode access-modes
| +--rw acl? -> /acl:access-lists/acl/name
+--ro clock-state
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| +--ro system-status
| +--ro clock-state ntp-clock-status
| +--ro clock-stratum ntp-stratum
| +--ro clock-refid union
| +--ro associations-address?
| | -> /ntp/associations/address
| +--ro associations-local-mode?
| | -> /ntp/associations/local-mode
| +--ro associations-isConfigured?
| | -> /ntp/associations/isConfigured
| +--ro nominal-freq decimal64
| +--ro actual-freq decimal64
| +--ro clock-precision uint8
| +--ro clock-offset? decimal64
| +--ro root-delay? decimal64
| +--ro root-dispersion? decimal64
| +--ro reference-time? yang:date-and-time
| +--ro sync-state ntp-sync-state
+--rw unicast-configuration* [address type]
| +--rw address inet:host
| +--rw type unicast-configuration-type
| +--rw authentication
| | +--rw (authentication-type)?
| | +--:(symmetric-key)
| | +--rw key-id? leafref
| +--rw prefer? boolean
| +--rw burst? boolean
| +--rw iburst? boolean
| +--rw source? if:interface-ref
| +--rw minpoll? ntp-minpoll
| +--rw maxpoll? ntp-maxpoll
| +--rw port? uint16 {ntp-port}?
| +--rw version? ntp-version
+--ro associations* [address local-mode isConfigured]
| +--ro address inet:host
| +--ro local-mode association-modes
| +--ro isConfigured boolean
| +--ro stratum? ntp-stratum
| +--ro refid? union
| +--ro authentication?
| | -> /ntp/authentication/authentication-keys/key-id
| +--ro prefer? boolean
| +--ro peer-interface? if:interface-ref
| +--ro minpoll? ntp-minpoll
| +--ro maxpoll? ntp-maxpoll
| +--ro port? uint16 {ntp-port}?
| +--ro version? ntp-version
| +--ro reach? uint8
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| +--ro unreach? uint8
| +--ro poll? uint8
| +--ro now? uint32
| +--ro offset? decimal64
| +--ro delay? decimal64
| +--ro dispersion? decimal64
| +--ro originate-time? yang:date-and-time
| +--ro receive-time? yang:date-and-time
| +--ro transmit-time? yang:date-and-time
| +--ro input-time? yang:date-and-time
| +--ro ntp-statistics
| +--ro packet-sent? yang:counter32
| +--ro packet-sent-fail? yang:counter32
| +--ro packet-received? yang:counter32
| +--ro packet-dropped? yang:counter32
+--rw interfaces
| +--rw interface* [name]
| +--rw name if:interface-ref
| +--rw broadcast-server!
| | +--rw ttl? uint8
| | +--rw authentication
| | | +--rw (authentication-type)?
| | | +--:(symmetric-key)
| | | +--rw key-id? leafref
| | +--rw minpoll? ntp-minpoll
| | +--rw maxpoll? ntp-maxpoll
| | +--rw port? uint16 {ntp-port}?
| | +--rw version? ntp-version
| +--rw broadcast-client!
| +--rw multicast-server* [address]
| | +--rw address
| | | rt-types:ip-multicast-group-address
| | +--rw ttl? uint8
| | +--rw authentication
| | | +--rw (authentication-type)?
| | | +--:(symmetric-key)
| | | +--rw key-id? leafref
| | +--rw minpoll? ntp-minpoll
| | +--rw maxpoll? ntp-maxpoll
| | +--rw port? uint16 {ntp-port}?
| | +--rw version? ntp-version
| +--rw multicast-client* [address]
| | +--rw address rt-types:ip-multicast-group-address
| +--rw manycast-server* [address]
| | +--rw address rt-types:ip-multicast-group-address
| +--rw manycast-client* [address]
| +--rw address
| | rt-types:ip-multicast-group-address
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| +--rw authentication
| | +--rw (authentication-type)?
| | +--:(symmetric-key)
| | +--rw key-id? leafref
| +--rw ttl? uint8
| +--rw minclock? uint8
| +--rw maxclock? uint8
| +--rw beacon? uint8
| +--rw minpoll? ntp-minpoll
| +--rw maxpoll? ntp-maxpoll
| +--rw port? uint16 {ntp-port}?
| +--rw version? ntp-version
+--ro ntp-statistics
+--ro packet-sent? yang:counter32
+--ro packet-sent-fail? yang:counter32
+--ro packet-received? yang:counter32
+--ro packet-dropped? yang:counter32
This data model defines one top-level container which includes both
the NTP configuration and the NTP running state including access
rules, authentication, associations, unicast configurations,
interfaces, system status and associations.
3. Relationship with NTPv4-MIB
If the device implements the NTPv4-MIB [RFC5907], data nodes from
YANG module can be mapped to table entries in NTPv4-MIB.
The following tables list the YANG data nodes with corresponding
objects in the NTPv4-MIB.
+--------------------------+--------------------------+
| YANG data nodes in /ntp/ | NTPv4-MIB objects |
+--------------------------+--------------------------+
| ntp-enabled | ntpEntStatusCurrentMode |
+--------------------------+--------------------------+
+--------------------------------------+---------------------+
| YANG data nodes in /ntp/associations | NTPv4-MIB objects |
+--------------------------------------+---------------------+
| address | ntpAssocAddressType |
| | ntpAssocAddress |
+--------------------------------------+---------------------+
YANG NTP Configuration Data Nodes and Related NTPv4-MIB Objects
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+---------------------------------+---------------------------------+
| YANG data nodes in /ntp/clock- | NTPv4-MIB objects |
| state/system-status | |
+---------------------------------+---------------------------------+
| clock-state | ntpEntStatusCurrentMode |
| clock-stratum | ntpEntStatusStratum |
| clock-refid | ntpEntStatusActiveRefSourceId |
| | ntpEntStatusActiveRefSourceName |
| clock-precision | ntpEntTimePrecision |
| clock-offset | ntpEntStatusActiveOffset |
| root-dispersion | ntpEntStatusDispersion |
+---------------------------------+---------------------------------+
+---------------------------------------+---------------------------+
| YANG data nodes in /ntp/associations/ | NTPv4-MIB objects |
+---------------------------------------+---------------------------+
| address | ntpAssocAddressType |
| | ntpAssocAddress |
| stratum | ntpAssocStratum |
| refid | ntpAssocRefId |
| offset | ntpAssocOffset |
| delay | ntpAssocStatusDelay |
| dispersion | ntpAssocStatusDispersion |
| ntp-statistics/packet-sent | ntpAssocStatOutPkts |
| ntp-statistics/packet-received | ntpAssocStatInPkts |
| ntp-statistics/packet-dropped | ntpAssocStatProtocolError |
+---------------------------------------+---------------------------+
YANG NTP State Data Nodes and Related NTPv4-MIB Objects
4. Relationship with RFC 7317
This section describes the relationship with NTP definition in
Section 3.2 System Time Management of [RFC7317] . YANG data nodes in
/ntp/ also supports per-interface configurations which is not
supported in /system/ntp
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+-------------------------------+--------------------------------+
| YANG data nodes in /ntp/ | YANG data nodes in /system/ntp |
+-------------------------------+--------------------------------+
| ntp-enabled | enabled |
| unicast-configuration | server |
| | server/name |
| unicast-configuration/address | server/transport/udp/address |
| unicast-configuration/port | server/transport/udp/port |
| unicast-configuration/type | server/association-type |
| unicast-configuration/iburst | server/iburst |
| unicast-configuration/prefer | server/prefer |
+-------------------------------+--------------------------------+
YANG NTP Configuration Data Nodes and counterparts in RFC 7317
Objects
5. NTP YANG Module
<CODE BEGINS> file "ietf-ntp@2018-03-05.yang"
module ietf-ntp {
namespace "urn:ietf:params:xml:ns:yang:ietf-ntp";
prefix "ntp";
import ietf-yang-types {
prefix "yang";
}
import ietf-inet-types {
prefix "inet";
}
import ietf-interfaces {
prefix "if";
}
import iana-crypt-hash {
prefix "ianach";
}
import ietf-key-chain {
prefix "key-chain";
}
import ietf-access-control-list {
prefix "acl";
}
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import ietf-routing-types {
prefix "rt-types";
}
organization
"IETF NTP (Network Time Protocol) Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/ntp/>
WG List: <mailto: ntpwg@lists.ntp.org
Editor: Eric Wu
<mailto:eric.wu@huawei.com>
Editor: Anil Kumar S N
<mailto:anil.ietf@gmail.com>
Editor: Yi Zhao
<mailto:yi.z.zhao@ericsson.com>
Editor: Dhruv Dhody
<mailto:dhruv.ietf@gmail.com>
Editor: Ankit Kumar Sinha
<mailto:ankit.ietf@gmail.com>";
description
"This YANG module defines essential components for the
management of a routing subsystem.
Copyright (c) 2018 IETF Trust and the persons identified
as authors of the code. All rights reserved.
Redistribution and use in source and binary forms,
with or without modification, is permitted pursuant to,
and subject to the license terms contained in, the
Simplified BSD License set forth in Section 4.c of the
IETF Trust's Legal Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX;
see the RFC itself for full legal notices.";
revision 2018-03-05 {
description
"Updated revision.";
reference
"RFC XXXX: A YANG Data Model for NTP Management";
}
/* Typedef Definitions */
typedef ntp-stratum {
type uint8 {
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range "1..16";
}
description
"The level of each server in the hierarchy is defined by
a stratum number. Primary servers are assigned stratum
one; secondary servers at each lower level are assigned
stratum numbers one greater than the preceding level";
}
typedef ntp-version {
type uint8 {
range "1..4";
}
default "3";
description
"The current NTP version supported by corresponding
association.";
}
typedef ntp-minpoll {
type uint8 {
range "4..17";
}
default "6";
description
"The minimum poll exponent for this NTP association.";
}
typedef ntp-maxpoll {
type uint8 {
range "4..17";
}
default "10";
description
"The maximul poll exponent for this NTP association.";
}
typedef access-modes {
type enumeration {
enum peer {
value "0";
description
"Sets the fully access authority. Both time
request and control query can be performed
on the local NTP service, and the local clock
can be synchronized to the remote server.";
}
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enum server {
value "1";
description
"Enables the server access and query.
Both time requests and control query can be
performed on the local NTP service, but the
local clock cannot be synchronized to the
remote server.";
}
enum synchronization {
value "2";
description
"Enables the server to access.
Only time request can be performed on the
local NTP service.";
}
enum query {
value "3";
description
"Sets the maximum access limitation.
Control query can be performed only on the
local NTP service.";
}
}
description
"This defines NTP acess modes.";
}
typedef unicast-configuration-type {
type enumeration {
enum server {
value "0";
description
"Use client association mode. This device
will not provide synchronization to the
configured NTP server.";
}
enum peer {
value "1";
description
"Use symmetric active association mode.
This device may provide synchronization
to the configured NTP server.";
}
}
description
"This defines NTP unicast mode of operation.";
}
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typedef association-modes {
type enumeration {
enum client {
value "0";
description
"Use client association mode(mode 3).
This device will not provide synchronization
to the configured NTP server.";
}
enum active {
value "1";
description
"Use symmetric active association mode(mode 1).
This device may synchronize with its NTP peer,
or provide synchronization to configured NTP peer.";
}
enum passive {
value "2";
description
"Use symmetric passive association mode(mode 2).
This device has learnt this asso dynamically.
This device may synchronize with its NTP peer.";
}
enum broadcast {
value "3";
description
"Use broadcast mode(mode 5).
This mode defines that its eigther working
as broadcast-server or multicast-server.";
}
enum broadcast-client {
value "4";
description
"This mode defines that its eigther working
as broadcast-client or multicast-client.";
}
}
description
"This defines NTP association modes.";
}
typedef ntp-clock-status {
type enumeration {
enum synchronized {
value "0";
description
"Indicates that the local clock has been
synchronized with an NTP server or
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the reference clock.";
}
enum unsynchronized {
value "1";
description
"Indicates that the local clock has not been
synchronized with any NTP server.";
}
}
description
"This defines NTP clock status.";
}
typedef ntp-sync-state {
type enumeration {
enum clock-not-set {
value "0";
description
"Indicates the clock is not updated.";
}
enum freq-set-by-cfg {
value "1";
description
"Indicates the clock frequency is set by
NTP configuration.";
}
enum clock-set {
value "2";
description
"Indicates the clock is set.";
}
enum freq-not-determined {
value "3";
description
"Indicates the clock is set but the frequency
is not determined.";
}
enum clock-synchronized {
value "4";
description
"Indicates that the clock is synchronized";
}
enum spike {
value "5";
description
"Indicates a time difference of more than 128
milliseconds is detected between NTP server
and client clock. The clock change will take
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effect in XXX seconds.";
}
}
description
"This defines NTP clock sync states.";
}
/* feature */
feature ntp-port {
description
"Indicates that the device supports the configuration of
the port for NTP.
This is a 'feature', since many implementations do not
support any port other than the default port.";
}
/* Groupings */
grouping authentication-key {
description
"To define an authentication key for a Network Time
Protocol (NTP) time source.";
leaf key-id {
type uint32 {
range "1..max";
}
description
"Authentication key identifier.";
}
leaf algorithm {
type identityref {
base key-chain:crypto-algorithm;
}
description
"Authentication algorithm.";
}
leaf password {
type ianach:crypt-hash;
description "Clear or encrypted mode for password text.";
}
}
grouping authentication-type-param {
description
"Authentication type.";
choice authentication-type {
description
"Type of authentication.";
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case symmetric-key {
leaf key-id {
type leafref {
path "/ntp:ntp/ntp:authentication/"
+ "ntp:authentication-keys/ntp:key-id";
}
description
"Authentication key id referenced in this
association.";
}
}
}
}
grouping statistics {
description
"NTP packet statistic.";
leaf packet-sent {
type yang:counter32;
description
"Indicates the total number of packets sent.";
}
leaf packet-sent-fail {
type yang:counter32;
description
"Indicates the number of times packet
sending failed.";
}
leaf packet-received {
type yang:counter32;
description
"Indicates the total number of packets received.";
}
leaf packet-dropped {
type yang:counter32;
description
"Indicates the number of packets dropped.";
}
}
grouping comman-attributes {
description
"NTP common attributes for configuration.";
leaf minpoll {
type ntp-minpoll;
description
"The minimum poll interval used in this association.";
}
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leaf maxpoll {
type ntp-maxpoll;
description
"The maximul poll interval used in this association.";
}
leaf port {
if-feature ntp-port;
type uint16 {
range "123 | 1025..max";
}
default "123";
description
"Specify the port used to send NTP packets.";
}
leaf version {
type ntp-version;
description
"NTP version.";
}
}
grouping association-ref {
description
"Reference to NTP association node";
leaf associations-address {
type leafref {
path "/ntp:ntp/ntp:associations/ntp:address";
}
description
"Indicates the association address
which result in clock synchronization.";
}
leaf associations-local-mode {
type leafref {
path "/ntp:ntp/ntp:associations/ntp:local-mode";
}
description
"Indicates the association local-mode
which result in clock synchronization.";
}
leaf associations-isConfigured {
type leafref {
path "/ntp:ntp/ntp:associations/"
+ "ntp:isConfigured";
}
description
"Indicates the association was configured or
dynamic which result in clock synchronization.";
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}
}
/* Configuration data nodes */
container ntp {
presence
"NTP is enable";
description
"Configuration parameters for NTP.";
leaf port {
if-feature ntp-port;
type uint16 {
range "123 | 1025..max";
}
default "123";
description
"Specify the port used to send NTP packets.";
}
container refclock-master {
presence
"NTP master clock is enable";
description
"Configures the device as NTP server.";
leaf master-stratum {
type ntp-stratum;
default "16";
description
"Stratum level from which NTP
clients get their time synchronized.";
}
}
container authentication {
description
"Configuration of authentication.";
leaf auth-enabled {
type boolean;
default false;
description
"Controls whether NTP authentication is enabled
or disabled on this device.";
}
list trusted-keys {
key "key-id";
description
"List of keys trusted by NTP.";
leaf key-id {
type leafref {
path "/ntp:ntp/ntp:authentication/"
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+ "ntp:authentication-keys/ntp:key-id";
}
description
"The key trusted by NTP.";
}
}
list authentication-keys {
key "key-id";
uses authentication-key;
description
"List of authentication key.";
}
}
container access-rules {
description
"Configuration of access rules.";
list access-rule {
key "access-mode";
description
"List of access rules.";
leaf access-mode {
type access-modes;
description
"NTP access mode.";
}
leaf acl {
type leafref {
path "/acl:access-lists/acl:acl/acl:name";
}
description
"NTP ACL.";
}
}
}
container clock-state {
config "false";
description
"Operational state of the NTP.";
container system-status {
description
"System status of NTP.";
leaf clock-state {
type ntp-clock-status;
mandatory true;
description "Indicates the state of system clock.";
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}
leaf clock-stratum {
type ntp-stratum;
mandatory true;
description
"Indicates the stratum of the reference clock.";
}
leaf clock-refid {
type union {
type inet:ipv4-address;
type binary {
length "4";
}
type string {
length "4";
}
}
mandatory true;
description
"IPv4 address or first 32 bits of the MD5 hash of
the IPv6 address or reference clock of the peer to
which clock is synchronized.";
}
uses association-ref {
description
"Reference to Association node";
}
leaf nominal-freq {
type decimal64 {
fraction-digits 4;
}
mandatory true;
description
"Indicates the nominal frequency of the
local clock, in Hz.";
}
leaf actual-freq {
type decimal64 {
fraction-digits 4;
}
mandatory true;
description
"Indicates the actual frequency of the
local clock, in Hz.";
}
leaf clock-precision {
type uint8;
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mandatory true;
description
"Precision of the clock of this system
in Hz.(prec=2^(-n))";
}
leaf clock-offset {
type decimal64 {
fraction-digits 4;
}
description
"Offset of clock to synchronized peer,
in milliseconds.";
}
leaf root-delay {
type decimal64 {
fraction-digits 2;
}
description
"Total delay along path to root clock,
in milliseconds.";
}
leaf root-dispersion {
type decimal64 {
fraction-digits 2;
}
description
"Indicates the dispersion between the local clock
and the master reference clock, in milliseconds.";
}
leaf reference-time {
type yang:date-and-time;
description
"Indicates reference timestamp.";
}
leaf sync-state {
type ntp-sync-state;
mandatory true;
description
"Indicates the synchronization status of
the local clock.";
}
}
}
list unicast-configuration {
key "address type";
description
"list of unicast-configuration.";
leaf address {
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type inet:host;
description
"The address of this association.";
}
leaf type {
type unicast-configuration-type;
description
"Type for this NTP configuration";
}
container authentication{
description
"Authentication type.";
uses authentication-type-param;
}
leaf prefer {
type boolean;
default "false";
description
"Whether this association is preferred.";
}
leaf burst {
type boolean;
default "false";
description
"Sends a series of packets instead of a single packet
within each synchronization interval to achieve faster
synchronization.";
}
leaf iburst {
type boolean;
default "false";
description
"Sends a series of packets instead of a single packet
within the initial synchronization interval to achieve
faster initial synchronization.";
}
leaf source {
type if:interface-ref;
description
"The interface whose ip address this association used
as source address.";
}
uses comman-attributes {
description
"Common attribute like port, version, min and max
poll.";
}
}
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list associations {
key "address local-mode isConfigured";
config "false";
description
"list of NTP association.";
leaf address {
type inet:host;
description
"The address of this association.";
}
leaf local-mode {
type association-modes;
description
"Local mode for this NTP association.";
}
leaf isConfigured {
type boolean;
description
"Whether this association is configured or
dynamically learnt.";
}
leaf stratum {
type ntp-stratum;
description
"Indicates the stratum of the reference clock.";
}
leaf refid {
type union {
type inet:ipv4-address;
type binary {
length "4";
}
type string {
length "4";
}
}
description
"Reference clock type or address for the peer.";
}
leaf authentication{
type leafref {
path "/ntp:ntp/ntp:authentication/"
+ "ntp:authentication-keys/ntp:key-id";
}
description
"Authentication Key used for this association.";
}
leaf prefer {
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type boolean;
default "false";
description
"Whether this association is preferred.";
}
leaf peer-interface {
type if:interface-ref;
description
"The interface which is used for communication.";
}
uses comman-attributes {
description
"Common attribute like port, version, min and
max poll.";
}
leaf reach {
type uint8;
description
"Indicates the reachability of the configured
server or peer.";
}
leaf unreach {
type uint8;
description
"Indicates the unreachability of the configured
server or peer.";
}
leaf poll {
type uint8;
description
"Indicates the polling interval for current,
in seconds.";
}
leaf now {
type uint32;
description
"Indicates the time since the NTP packet was
not received or last synchronized, in seconds.";
}
leaf offset {
type decimal64 {
fraction-digits 4;
}
description
"Indicates the offset between the local clock
and the superior reference clock.";
}
leaf delay {
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type decimal64 {
fraction-digits 2;
}
description
"Indicates the delay between the local clock
and the superior reference clock.";
}
leaf dispersion {
type decimal64 {
fraction-digits 2;
}
description
"Indicates the dispersion between the local
clock and the superior reference clock.";
}
leaf originate-time {
type yang:date-and-time;
description
"Indicates packet originate timestamp(T1).";
}
leaf receive-time {
type yang:date-and-time;
description
"Indicates packet receive timestamp(T2).";
}
leaf transmit-time {
type yang:date-and-time;
description
"Indicates packet transmit timestamp(T3).";
}
leaf input-time {
type yang:date-and-time;
description
"Indicates packet input timestamp(T4).";
}
container ntp-statistics {
description
"Per Peer packet send and receive statistic.";
uses statistics {
description
"NTP send and receive packet statistic.";
}
}
}
container interfaces {
description
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"Configuration parameters for NTP interfaces.";
list interface {
key "name";
description
"List of interfaces.";
leaf name {
type if:interface-ref;
description
"The interface name.";
}
container broadcast-server {
presence
"NTP broadcast-server is configured";
description
"Configuration of broadcast server.";
leaf ttl {
type uint8;
description
"Specifies the time to live (TTL) of a
broadcast packet.";
}
container authentication{
description
"Authentication type.";
uses authentication-type-param;
}
uses comman-attributes {
description
"Common attribute like port, version, min and
max poll.";
}
}
container broadcast-client {
presence
"NTP broadcast-client is configured";
description
"Configuration of broadcast-client.";
}
list multicast-server {
key "address";
description
"Configuration of multicast server.";
leaf address {
type rt-types:ip-multicast-group-address;
description
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"The IP address to send NTP multicast packets.";
}
leaf ttl {
type uint8;
description
"Specifies the time to live (TTL) of a
multicast packet.";
}
container authentication{
description
"Authentication type.";
uses authentication-type-param;
}
uses comman-attributes {
description
"Common attribute like port, version, min and
max poll.";
}
}
list multicast-client {
key "address";
description
"Configuration of multicast-client.";
leaf address {
type rt-types:ip-multicast-group-address;
description
"The IP address of the multicast group to
join.";
}
}
list manycast-server {
key "address";
description
"Configuration of manycast server.";
leaf address {
type rt-types:ip-multicast-group-address;
description
"The multicast group IP address to receive
manycast client messages .";
}
}
list manycast-client {
key "address";
description
"Configuration of manycast-client.";
leaf address {
type rt-types:ip-multicast-group-address;
description
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"The group IP address that the manycast client
broadcasts the request message to.";
}
container authentication{
description
"Authentication type.";
uses authentication-type-param;
}
leaf ttl {
type uint8;
description
"Specifies the maximum time to live (TTL) for
the expanding ring search.";
}
leaf minclock {
type uint8;
description
"The minimum manycast survivors in this
association.";
}
leaf maxclock {
type uint8;
description
"The maximum manycast candidates in this
association.";
}
leaf beacon {
type uint8;
description
"The maximum interval between beacons in this
association.";
}
uses comman-attributes {
description
"Common attribute like port, version, min and
max poll.";
}
}
}
}
container ntp-statistics {
config "false";
description
"Total NTP packet statistic.";
uses statistics {
description
"NTP send and receive packet statistic.";
}
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}
}
}
<CODE ENDS>
6. Usage Example
6.1. Unicast association
Below is the example on how to configure a preferred unicast server
present at 1.1.1.1 running at port 1025 with authentication-key 10
and version 4
<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<unicast-configuration>
<address>1.1.1.1</address>
<type>server</type>
<prefer>true</prefer>
<version>4</version>
<port>1025</port>
<authentication>
<symmetric-key>
<key-id>10</key-id>
</symmetric-key>
</authentication>
</unicast-configuration>
</ntp>
</config>
</edit-config>
Below is the example on how to get unicast configuration
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:unicast-configuration>
</sys:unicast-configuration>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
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<unicast-configuration>
<address>1.1.1.1</address>
<type>server</type>
<authentication>
<symmetric-key>
<key-id>10</key-id>
</symmetric-key>
</authentication>
<prefer>true</prefer>
<burst>false</burst>
<iburst>true</iburst>
<source/>
<minpoll>6</minpoll>
<maxpoll>10</maxpoll>
<port>1025</port>
<version>4</version>
<stratum>9</stratum>
<refid>20.1.1.1</refid>
<reach>255</reach>
<unreach>0</unreach>
<poll>128</poll>
<now>10</now>
<offset>0.025</offset>
<delay>0.5</delay>
<dispersion>0.6</dispersion>
<originate-time>10-10-2017 07:33:55.253 Z+05:30
</originate-time>
<receive-time>10-10-2017 07:33:55.258 Z+05:30
</receive-time>
<transmit-time>10-10-2017 07:33:55.300 Z+05:30
</transmit-time>
<input-time>10-10-2017 07:33:55.305 Z+05:30
</input-time>
<ntp-statistics>
<packet-sent>20</packet-sent>
<packet-sent-fail>0</packet-sent-fail>
<packet-received>20</packet-received>
<packet-dropped>0</packet-dropped>
</ntp-statistics>
</unicast-configuration>
</ntp>
</data>
6.2. Refclock master
Below is the example on how to configure reference clock with stratum
8
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<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<refclock-master>
<master-stratum>8</master-stratum>
</refclock-master>
</ntp>
</config>
</edit-config>
Below is the example on how to get reference clock configuration
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:refclock-master>
</sys:refclock-master>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<refclock-master>
<master-stratum>8</master-stratum>
</refclock-master>
</ntp>
</data>
6.3. Authentication configuration
Below is the example on how to enable authentication and configure
authentication key 10 with mode as md5 and password as abcd
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<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<authentication>
<auth-enabled>true</auth-enabled>
<authentication-keys>
<key-id>10</key-id>
<algorithm>md5</algorithm>
<password>abcd</password>
</authentication-keys>
</authentication>
</ntp>
</config>
</edit-config>
Below is the example on how to get authentication related
configuration
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:authentication>
</sys:authentication>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<authentication>
<auth-enabled>false</auth-enabled>
<trusted-keys/>
<authentication-keys>
<key-id>10</key-id>
<algorithm>md5</algorithm>
<password>abcd</password>
</authentication-keys>
</authentication>
</ntp>
</data>
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6.4. Access configuration
Below is the example on how to configure acess type peer associated
with acl 2000
<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<access-rules>
<access-rule>
<access-mode>peer</access-mode>
<acl>2000</acl>
</access-rule>
</access-rules>
</ntp>
</config>
</edit-config>
Below is the example on how to get access related configuration
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:access-rules>
</sys:access-rules>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<access-rules>
<access-rule>
<access-mode>peer</access-mode>
<acl>2000</acl>
</access-rule>
</access-rules>
</ntp>
</data>
6.5. Multicast configuration
Below is the example on how to configure multicast-server with
address as 224.1.1.1, port as 1025 and authentication keyid as 10
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<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<multicast-server>
<address>224.1.1.1</address>
<authentication>
<symmetric-key>
<key-id>10</key-id>
</symmetric-key>
</authentication>
<port>1025</port>
</multicast-server>
</interface>
</interfaces>
</ntp>
</config>
</edit-config>
Below is the example on how to get multicast-server related
configuration
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<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:interfaces>
<sys:interface>
<sys:multicast-server>
</sys:multicast-server>
</sys:interface>
</sys:interfaces>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<multicast-server>
<address>224.1.1.1</address>
<ttl>224.1.1.1</ttl>
<authentication>
<symmetric-key>
<key-id>10</key-id>
</symmetric-key>
</authentication>
<minpoll>6</minpoll>
<maxpoll>10</maxpoll>
<port>1025</port>
<version>3</version>
</multicast-server>
</interface>
</interfaces>
</ntp>
</data>
Below is the example on how to configure multicast-client with
address as 224.1.1.1
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<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<multicast-client>
<address>224.1.1.1</address>
</multicast-client>
</interface>
</interfaces>
</ntp>
</config>
</edit-config>
Below is the example on how to get multicast-client related
configuration
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:interfaces>
<sys:interface>
<sys:multicast-client>
</sys:multicast-client>
</sys:interface>
</sys:interfaces>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<multicast-client>
<address>224.1.1.1</address>
</multicast-client>
</interface>
</interfaces>
</ntp>
</data>
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6.6. Manycast configuration
Below is the example on how to configure manycast-client with address
as 224.1.1.1, port as 1025 and authentication keyid as 10
<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<manycast-client>
<address>224.1.1.1</address>
<authentication>
<symmetric-key>
<key-id>10</key-id>
</symmetric-key>
</authentication>
<port>1025</port>
</manycast-client>
</interface>
</interfaces>
</ntp>
</config>
</edit-config>
Below is the example on how to get manycast-client related
configuration
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<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:interfaces>
<sys:interface>
<sys:manycast-client>
</sys:manycast-client>
</sys:interface>
</sys:interfaces>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<manycast-client>
<address>224.1.1.1</address>
<authentication>
<symmetric-key>
<key-id>10</key-id>
</symmetric-key>
</authentication>
<ttl>255</ttl>
<minclock>3</minclock>
<maxclock>10</maxclock>
<beacon>6</beacon>
<minpoll>6</minpoll>
<maxpoll>10</maxpoll>
<port>1025</port>
</manycast-client>
</interface>
</interfaces>
</ntp>
</data>
Below is the example on how to configure manycast-server with address
as 224.1.1.1
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<edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<running/>
</target>
<config>
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<manycast-server>
<address>224.1.1.1</address>
</manycast-server>
</interface>
</interfaces>
</ntp>
</config>
</edit-config>
Below is the example on how to get manycast-server related
configuration
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:interfaces>
<sys:interface>
<sys:manycast-server>
</sys:manycast-server>
</sys:interface>
</sys:interfaces>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<interfaces>
<interface>
<name>Ethernet3/0/0</name>
<manycast-server>
<address>224.1.1.1</address>
</manycast-server>
</interface>
</interfaces>
</ntp>
</data>
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6.7. Clock state
Below is the example on how to get clock current state
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:clock-state>
</sys:clock-state>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<clock-state>
<system-status>
<clock-state>synchronized</clock-state>
<clock-stratum>7</clock-stratum>
<clock-refid>1.1.1.1</clock-refid>
<associations-address>1.1.1.1
</associations-address>
<associations-local-mode>client
</associations-local-mode>
<associations-isConfigured>yes
</associations-isConfigured>
<nominal-freq>100.0</nominal-freq>
<actual-freq>100.0</actual-freq>
<clock-precision>18</clock-precision>
<clock-offset>0.025</clock-offset>
<root-delay>0.5</root-delay>
<root-dispersion>0.8</root-dispersion>
<reference-time>10-10-2017 07:33:55.258 Z+05:30
</reference-time>
<sync-state>clock-synchronized</sync-state>
</system-status>
</clock-state>
</ntp>
</data>
6.8. Get all association
Below is the example on how to get all association present
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<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:associations>
</sys:associations>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<associations>
<address>1.1.1.1</address>
<stratum>9</stratum>
<refid>20.1.1.1</refid>
<local-mode>client</local-mode>
<isConfigured>true</isConfigured>
<authentication-key>10</authentication-key>
<prefer>true</prefer>
<peer-interface>Ethernet3/0/0</peer-interface>
<minpoll>6</minpoll>
<maxpoll>10</maxpoll>
<port>1025</port>
<version>4</version>
<reach>255</reach>
<unreach>0</unreach>
<poll>128</poll>
<now>10</now>
<offset>0.025</offset>
<delay>0.5</delay>
<dispersion>0.6</dispersion>
<originate-time>10-10-2017 07:33:55.253 Z+05:30
</originate-time>
<receive-time>10-10-2017 07:33:55.258 Z+05:30
</receive-time>
<transmit-time>10-10-2017 07:33:55.300 Z+05:30
</transmit-time>
<input-time>10-10-2017 07:33:55.305 Z+05:30
</input-time>
<ntp-statistics>
<packet-sent>20</packet-sent>
<packet-sent-fail>0</packet-sent-fail>
<packet-received>20</packet-received>
<packet-dropped>0</packet-dropped>
</ntp-statistics>
</associations>
</ntp>
</data>
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6.9. Global statistic
Below is the example on how to get clock current state
<get>
<filter type="subtree">
<sys:ntp xmlns:sys="urn:ietf:params:xml:ns:yang:ietf-ntp">
<sys:ntp-statistics>
</sys:ntp-statistics>
</sys:ntp>
</filter>
</get>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ntp xmlns="urn:ietf:params:xml:ns:yang:ietf-ntp">
<ntp-statistics>
<packet-sent>30</packet-sent>
<packet-sent-fail>5</packet-sent-fail>
<packet-received>20</packet-received>
<packet-dropped>2</packet-dropped>
</ntp-statistics>
</ntp>
</data>
7. IANA Considerations
This document registers a URI in the "IETF XML Registry" [RFC3688].
Following the format in RFC 3688, the following registration has been
made.
URI: urn:ietf:params:xml:ns:yang:ietf-ntp
Registrant Contact: The NETMOD WG of the IETF.
XML: N/A; the requested URI is an XML namespace.
This document registers a YANG module in the "YANG Module Names"
registry [RFC6020].
Name: ietf-ntp
Namespace: urn:ietf:params:xml:ns:yang:ietf-ntp
Prefix: ntp
Reference: RFC XXXX
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8. Security Considerations
The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such
as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer
is the secure transport layer, and the mandatory-to-implement secure
transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer
is HTTPS, and the mandatory-to-implement secure transport is TLS
[RFC5246].
The NETCONF access control model [RFC6536] provides the means to
restrict access for particular NETCONF or RESTCONF users to a
preconfigured subset of all available NETCONF or RESTCONF protocol
operations and content.
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. These are the subtrees and data nodes
and their sensitivity/vulnerability:
/ntp/port - This data node specify the port number to be used to
send NTP packets. Unexpected changes could lead to disruption
and/or network misbehavior.
/ntp/authentication and /ntp/access-rules - The entries in the
list include the authentication and access control configurations.
Car should be taken while setting these parameters.
/ntp/unicast-configuration - The entries in the list include all
unicast configurations (server or peer mode), and indirectly
creates or modify the NTP associations. Unexpected changes could
lead to disruption and/or network misbehavior.
/ntp/interfaces/interface - The entries in the list inclide all
per-interface configurations related to broadcast, multicast and
manycast mode, and indirectly creates or modify the NTP
associations. Unexpected changes could lead to disruption and/or
network misbehavior.
Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control read access (e.g., via get, get-config, or
notification) to these data nodes. These are the subtrees and data
nodes and their sensitivity/vulnerability:
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/ntp/associations - The entries in the list includes all active
NTP associations of all modes. Unauthorized access to this needs
to be curtailed.
9. Acknowledgments
The authors would like to express their thanks to Sladjana Zoric,
Danny Mayer, Harlan Stenn, Ulrich Windl, Miroslav Lichvar, and
Maurice Angermann for their review and suggestions.
10. References
10.1. Normative References
[I-D.ietf-netmod-yang-tree-diagrams]
Bjorklund, M. and L. Berger, "YANG Tree Diagrams", draft-
ietf-netmod-yang-tree-diagrams-06 (work in progress),
February 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
[RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,
"Network Time Protocol Version 4: Protocol and Algorithms
Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010,
<https://www.rfc-editor.org/info/rfc5905>.
[RFC5907] Gerstung, H., Elliott, C., and B. Haberman, Ed.,
"Definitions of Managed Objects for Network Time Protocol
Version 4 (NTPv4)", RFC 5907, DOI 10.17487/RFC5907, June
2010, <https://www.rfc-editor.org/info/rfc5907>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
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[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536,
DOI 10.17487/RFC6536, March 2012,
<https://www.rfc-editor.org/info/rfc6536>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
10.2. Informative References
[I-D.ietf-netmod-revised-datastores]
Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore
Architecture", draft-ietf-netmod-revised-datastores-10
(work in progress), January 2018.
[RFC7317] Bierman, A. and M. Bjorklund, "A YANG Data Model for
System Management", RFC 7317, DOI 10.17487/RFC7317, August
2014, <https://www.rfc-editor.org/info/rfc7317>.
Authors' Addresses
Nan Wu
Huawei
Huawei Bld., No.156 Beiqing Rd.
Beijing 100095
China
Email: eric.wu@huawei.com
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Anil Kumar S N
RtBrick Inc.
Bangalore, Kanataka
India
Email: anil.ietf@gmail.com
Yi Zhao
Ericsson
China Digital Kingdom Bld., No.1 WangJing North Rd.
Beijing 100102
China
Email: yi.z.zhao@ericsson.com
Dhruv Dhody
Huawei
Divyashree Techno Park, Whitefield
Bangalore, Kanataka 560066
India
Email: dhruv.ietf@gmail.com
Ankit kumar Sinha
RtBrick Inc.
Bangalore, Kanataka
India
Email: ankit.ietf@gmail.com
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