One document matched: draft-ietf-netconf-server-model-05.xml
<?xml version='1.0'?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd" [
<!ENTITY rfc2119 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.2119.xml">
<!ENTITY rfc4251 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.4251.xml">
<!ENTITY rfc4252 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.4252.xml">
<!ENTITY rfc4253 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.4253.xml">
<!ENTITY rfc5246 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.5246.xml">
<!ENTITY rfc6020 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6020.xml">
<!ENTITY rfc6187 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6187.xml">
<!ENTITY rfc6241 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6241.xml">
<!ENTITY rfc6242 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6242.xml">
<!ENTITY rfc6335 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6335.xml">
<!ENTITY rfc6520 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6520.xml">
<!ENTITY rfc6536 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6536.xml">
<!ENTITY rfc6991 SYSTEM "http://xml.resource.org/public/rfc/bibxml/reference.RFC.6991.xml">
]>
<?rfc toc="yes"?>
<?rfc symrefs="yes"?>
<?rfc sortrefs="yes" ?>
<?rfc compact="yes"?>
<?rfc subcompact="no"?>
<?rfc linkmailto="no" ?>
<?rfc editing="no" ?>
<?rfc comments="yes" ?>
<?rfc inline="yes"?>
<?rfc rfcedstyle="yes"?>
<?rfc-ext allow-markup-in-artwork="yes" ?>
<?rfc-ext include-index="no" ?>
<!--<?rfc strict="no"?> -->
<rfc category="std"
ipr="trust200902"
docName="draft-ietf-netconf-server-model-05" >
<front>
<title abbrev="NETCONF/RESTCONF Server Config Models">NETCONF Server and RESTCONF Server Configuration Models</title>
<author initials="K.W." surname="Watsen" fullname="Kent Watsen">
<organization>Juniper Networks</organization>
<address>
<email>kwatsen@juniper.net</email>
</address>
</author>
<author initials="J.S." surname="Schoenwaelder" fullname="Juergen Schoenwaelder">
<organization>Jacobs University Bremen</organization>
<address>
<email>j.schoenwaelder@jacobs-university.de</email>
</address>
</author>
<date/>
<area>Operations</area>
<workgroup>NETCONF Working Group</workgroup>
<abstract>
<t>This draft defines a NETCONF server configuration data model and a RESTCONF
server configuration data model. These data models enable configuration of
the NETCONF and RESTCONF services themselves, including which transports are
supported, what ports the servers listens on, whether call-home is supported,
and associated parameters.</t>
</abstract>
<note title="Editorial Note (To be removed by RFC Editor)">
<t>This draft contains many placeholder values that need to be replaced
with finalized values at the time of publication. This note summarizes
all of the substitutions that are needed. Please note that no other
RFC Editor instructions are specified anywhere else in this document.</t>
<t>This document contains references to other drafts in progress, both in
the Normative References section, as well as in body text throughout.
Please update the following references to reflect their final RFC assignments:
<list style="symbols">
<t>draft-ietf-netconf-rfc5539bis</t>
<t>draft-ietf-netconf-restconf</t>
<t>draft-ietf-netconf-call-home</t>
<t>draft-ietf-netmod-snmp-cfg</t>
</list>
</t>
<t>Artwork in this document contains shorthand references to drafts in
progress. Please apply the following replacements:
<list style="symbols">
<t><spanx style="verb">VVVV</spanx> --> the assigned RFC value for this draft</t>
<t><spanx style="verb">WWWW</spanx> --> the assigned RFC value for draft-ietf-netconf-rfc5539bis</t>
<t><spanx style="verb">XXXX</spanx> --> the assigned RFC value for draft-ietf-netconf-restconf</t>
<t><spanx style="verb">YYYY</spanx> --> the assigned RFC value for draft-ietf-netconf-call-home</t>
<t><spanx style="verb">ZZZZ</spanx> --> the assigned RFC value for draft-ietf-netmod-snmp-cfg</t>
</list>
</t>
<t>Artwork in this document contains placeholder values for ports pending IANA assignment
from "draft-ietf-netconf-call-home". Please apply the following replacements:
<list style="symbols">
<t><spanx style="verb">7777</spanx> --> the assigned port value for "netconf-ch-ssh"</t>
<t><spanx style="verb">8888</spanx> --> the assigned port value for "netconf-ch-tls"</t>
<t><spanx style="verb">9999</spanx> --> the assigned port value for "restconf-ch-tls"</t>
</list>
</t>
<t>Artwork in this document contains placeholder values for the date of publication of this
draft. Please apply the following replacement:
<list style="symbols">
<t><spanx style="verb">2014-12-11</spanx> --> the publication date of this draft</t>
</list>
</t>
<t>The following two Appendix sections are to be removed prior to publication:
<list style="symbols">
<t>Appendix B. Change Log</t>
<t>Appendix C. Open Issues</t>
</list>
</t>
</note>
</front>
<middle>
<section title="Introduction">
<t>This draft defines a NETCONF <xref target="RFC6241"/> server
configuration data model and a RESTCONF <xref target="draft-ietf-netconf-restconf"/>
server configuration data model. These data models enable configuration of
the NETCONF and RESTCONF services themselves, including which transports are
supported, what ports the servers listens on, whether call-home is supported,
and associated parameters.</t>
<section title="Terminology">
<t>The keywords "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 <xref target="RFC2119"/>.</t>
</section>
<section title="Tree Diagrams">
<t>A simplified graphical representation of the data models
is used in this document. The meaning of the symbols in
these diagrams is as follows:
<list style="symbols">
<t>Brackets "[" and "]" enclose list keys.</t>
<t>Abbreviations before data node names: "rw" means
configuration (read-write) and "ro" state data
(read-only).</t>
<t>Symbols after data node names: "?" means an optional
node, "!" means a presence container, and "*" denotes a
list and leaf-list.</t>
<t>Parentheses enclose choice and case nodes, and case
nodes are also marked with a colon (":").</t>
<t>Ellipsis ("...") stands for contents of subtrees that
are not shown.</t>
</list>
</t>
</section>
</section>
<section title="Objectives">
<t>The primary purpose of the YANG modules defined herein is
to enable the configuration of the NETCONF and RESTCONF
services on a network element. This scope includes the following
objectives:</t>
<section title="Support all NETCONF and RESTCONF transports">
<t>The YANG module should support all current NETCONF and RESTCONF
transports, namely NETCONF over SSH <xref target="RFC6242"/>,
NETCONF over TLS <xref target="draft-ietf-netconf-rfc5539bis"/>, and RESTCONF over
TLS <xref target="draft-ietf-netconf-restconf"/>, and to be
extensible to support future transports as necessary.</t>
<t>Because implementations may not support all transports,
the module should use YANG "feature" statements
so that implementations can accurately advertise which
transports are supported.</t>
</section>
<section title="Enable each transport to select which keys to use">
<t>Servers may have a multiplicity of host-keys or server-certificates
from which subsets may be selected for specific uses. For instance,
a NETCONF server may want to use one set of SSH host-keys when listening
on port 830, and a different set of SSH host-keys when calling
home. The data models provided herein should enable configuration
of which keys to use on a per-use basis.</t>
</section>
<section title="Support authenticating NETCONF clients certificates">
<t>When a certificate is used to authenticate a NETCONF client, either when
using the TLS transport or the SSH transport with X.509 certificates
<xref target="RFC6187"/>, there is a need to configure the server to
know how to authenticate the certificates. The server should be able
to do this either by using path-validation to a configured trust anchor
or by matching the client-certificate to one previously configured.</t>
</section>
<section title="Support mapping authenticated NETCONF client-certificates to usernames">
<t>Some NETCONF transports (e.g., TLS) need additional support to map authenticated
transport-level sessions to a NETCONF username. The NETCONF server model
defined herein should define an ability for this mapping to be configured."</t>
</section>
<section title="Support both Listening for connections and Call Home">
<t>The NETCONF and RESTCONF protocols were originally defined as having the
server opening a port to listen for client connections. More recently
the NETCONF working group defined support for call-home
(<xref target="draft-ietf-netconf-call-home"/>), enabling the server to
initiate the connection to the client, for both the NETCONF and RESTCONF
protocols. Thus the modules defined herein should enable configuration
for both listening for connections and calling home.
Because implementations may not support both listening for
connections and calling home, YANG "feature" statements
should be used so that implementation can accurately
advertise the connection types it supports.</t>
</section>
<section title="For Call Home connections">
<t>The following objectives only pertain to call home connections.</t>
<section title="Support more than one northbound application">
<t>A device may be managed by more than one northbound
application. For instance, a deployment may have one
application for provisioning and another for fault
monitoring. Therefore, when it is desired for a device
to initiate call home connections, it should be able to
do so to more than one application.</t>
</section>
<section title="Support applications having more than one server">
<t>An application managing a device may implement a
high-availability strategy employing a multiplicity of
active and/or passive servers. Therefore, when it is
desired for a device to initiate call home connections,
it should be able to connect to any of the application's
servers.</t>
</section>
<section title="Support a reconnection strategy">
<t>Assuming an application has more than one server, then
it becomes necessary to configure how a device should
reconnect to the application should it lose its
connection to the application's servers.
Of primary interest is if the device should
start with first server defined in a user-ordered
list of servers or with the last server it was connected
to. Secondary settings might specify the frequency of
attempts and number of attempts per server. Therefore,
a reconnection strategy should be configurable.</t>
</section>
<section title="Support both persistent and periodic connections">
<t>Applications may vary greatly on how frequently they
need to interact with a device, how responsive interactions
with devices need to be, and how many simultaneous connections
they can support. Some applications may need a persistent
connection to devices to optimize real-time interactions,
while others prefer periodic interactions in order to minimize
resource requirements. Therefore, when it is necessary
for devices to initiate connections, the type of connection
desired should be configurable.</t>
</section>
<section title="Reconnection strategy for periodic connections">
<t>The reconnection strategy should apply to both
persistent and periodic connections. How it
applies to periodic connections becomes clear when
considering that a periodic "connection" is
a logical connection to a single server. That is,
the periods of unconnectedness are intentional as
opposed to due to external reasons. A periodic
"connection" should always reconnect to
the same server until it is no longer able to, at
which time the reconnection strategy guides how to
connect to another server.</t>
</section>
<section anchor="keepalives" title="Keep-alives for persistent connections">
<t>If a persistent connection is desired, it is the
responsibility of the connection-initiator to actively
test the "aliveness" of the connection. The connection
initiator must immediately work to reestablish a
persistent connection as soon as the connection is
lost. How often the connection should be tested is
driven by application requirements, and therefore
keep-alive settings should be configurable on a
per-application basis.</t>
</section>
<section title="Customizations for periodic connections">
<t>If a periodic connection is desired, it is necessary
for the device to know how often it should connect. This
delay essentially determines how long the
application might have to wait to send data to the device.
This setting does not constrain how often the
device must wait to send data to the application, as the
device should immediately connect to the application
whenever it has data to send to it.</t>
<t>A common communication pattern is that one data
transmission is many times closely followed by
another. For instance, if the device needs to send a
notification message, there's a high probability that
it will send another shortly thereafter. Likewise,
the application may have a sequence of pending messages
to send. Thus, it should be possible for a device to
hold a connection open until some amount of time of no
data being transmitted as transpired.</t>
</section>
</section>
</section>
<section title="The NETCONF Server Configuration Model">
<section title="Overview">
<section title="The "session-options" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-netconf-server
+--rw netconf-server
+--rw session-options {session-options}?
+--rw hello-timeout? uint32
+--rw idle-timeout? uint32
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-netconf-server YANG module
enables configuration of NETCONF session options,
independent of any transport or connection strategy.
A feature statement is used for the server to advertise
support for configuring these NETCONF server options.
Please see the YANG module (<xref target="netconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
<section title="The "listen" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-netconf-server
+--rw netconf-server
+--rw listen {listen}?
+--rw max-sessions? uint16
+--rw endpoint* [name]
+--rw name string
+--rw (transport)
| +--:(ssh) {ssh}?
| | +--rw ssh
| | +--rw address? inet:ip-address
| | +--rw port? inet:port-number
| | +--rw host-keys
| | +--rw host-key* string
| +--:(tls) {tls}?
| +--rw tls
| +--rw address? inet:ip-address
| +--rw port? inet:port-number
| +--rw certificates
| +--rw certificate* string
+--rw keep-alives
+--rw interval-secs? uint8
+--rw count-max? uint8
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-netconf-server YANG module
enables configuration for listening for remote connections,
as described in <xref target="RFC6242"/> and <xref
target="draft-ietf-netconf-call-home"/>. Feature statements are used to limit both
if listening is supported at all as well as for which transports.
If listening for connections is supported, then the model
enables configuring a list of listening endpoints, each
configured with a
user-specified name (the key field), the transport to use
(i.e. SSH, TLS), and the IP address and port to listen on.
The port field is optional, defaulting to the transport-specific
port when not configured.
Please see the YANG module (<xref target="netconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
<section title="The "call-home" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-netconf-server
+--rw netconf-server
+--rw call-home {call-home}?
+--rw application* [name]
+--rw name string
+--rw (transport)
| +--:(ssh) {ssh}?
| | +--rw ssh
| | +--rw endpoints
| | | +--rw endpoint* [name]
| | | +--rw name string
| | | +--rw address inet:host
| | | +--rw port? inet:port-number
| | +--rw host-keys
| | +--rw host-key* string
| +--:(tls) {tls}?
| +--rw tls
| +--rw endpoints
| | +--rw endpoint* [name]
| | +--rw name string
| | +--rw address inet:host
| | +--rw port? inet:port-number
| +--rw certificates
| +--rw certificate* string
+--rw connection-type
| +--rw (connection-type)?
| +--:(persistent-connection)
| | +--rw persistent
| | +--rw keep-alives
| | +--rw interval-secs? uint8
| | +--rw count-max? uint8
| +--:(periodic-connection)
| +--rw periodic
| +--rw timeout-mins? uint8
| +--rw linger-secs? uint8
+--rw reconnect-strategy
+--rw start-with? enumeration
+--rw interval-secs? uint8
+--rw count-max? uint8
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-netconf-server YANG module
enables configuration for call home, as described in
<xref target="draft-ietf-netconf-call-home"/>. Feature
statements are used to limit both if call-home is supported
at all as well as for which transports, if it is. If call-home
is supported, then the model supports configuring a list of
applications to connect to. Each application is configured
with a user-specified name (the key field), the transport to
be used (i.e. SSH, TLS), and a list of remote endpoints, each
having a name, an IP address, and an optional port. Additionally,
the configuration for each remote application indicates the
connection-type (persistent vs. periodic) and associated
parameters, as well as the reconnection strategy to use.
Please see the YANG module (<xref target="netconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
<section title="The "ssh" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-netconf-server
+--rw netconf-server
+--rw ssh {ssh}?
+--rw x509 {rfc6187}?
+--rw trusted-ca-certs
| +--rw trusted-ca-cert* binary
+--rw trusted-client-certs
+--rw trusted-client-cert* binary
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-netconf-server YANG module
enables some SSH configuration independent of if the NETCONF
server is listening or calling home. Specifically, when
RFC 6187 is supported, this data model provides an ability
to configure how client-certificates are authenticated.
Please see the YANG module (<xref target="netconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
<section title="The "tls" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-netconf-server
+--rw netconf-server
+--rw tls {tls}?
+--rw client-auth
+--rw trusted-ca-certs
| +--rw trusted-ca-cert* binary
+--rw trusted-client-certs
| +--rw trusted-client-cert* binary
+--rw cert-maps
+--rw cert-to-name* [id]
+--rw id uint32
+--rw fingerprint x509c2n:tls-fingerprint
+--rw map-type identityref
+--rw name string
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-netconf-server YANG module
enables TLS configuration independent of if the NETCONF
server is listening or calling home. Specifically, this
data-model provides 1) an ability to configure how
client-certificates are authenticated and 2) how authenticated
client-certificates are mapped to NETCONF user names.
Please see the YANG module (<xref target="netconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
</section>
<section title="YANG Module" anchor="netconf-yang-module">
<t>This YANG module imports YANG types from <xref
target="RFC6991"/>, and
<xref target="draft-ietf-netmod-snmp-cfg"/>.</t>
<t>
<figure>
<!--<preamble>The YANG Module</preamble>-->
<artwork><![CDATA[
<CODE BEGINS> file "ietf-netconf-server@2014-12-11.yang"
module ietf-netconf-server {
namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-server";
prefix "ncserver";
import ietf-inet-types { // RFC 6991
prefix inet;
revision-date 2013-07-15;
}
import ietf-x509-cert-to-name { // RFC ZZZZ
prefix x509c2n;
revision-date 2014-05-06;
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
WG Chair: Mehmet Ersue
<mailto:mehmet.ersue@nsn.com>
WG Chair: Mahesh Jethanandani
<mailto:mjethanandani@gmail.com>
Editor: Kent Watsen
<mailto:kwatsen@juniper.net>";
description
"This module contains a collection of YANG definitions for
configuring NETCONF servers.
Copyright (c) 2014 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 VVVV; see
the RFC itself for full legal notices.";
revision "2014-12-11" {
description
"Initial version";
reference
"RFC VVVV: NETCONF Server and RESTCONF Server Configuration Models";
}
// Features
feature session-options {
description
"The session-options feature indicates that the NETCONF server
supports the session-options container.";
}
feature ssh {
description
"The ssh feature indicates that the server supports the
SSH transport protocol.";
reference
"RFC 6242: Using the NETCONF Protocol over Secure Shell (SSH)";
}
feature tls {
description
"The tls feature indicates that the server supports the
TLS transport protocol.";
reference
"RFC 5539: NETCONF over Transport Layer Security (TLS)";
}
feature listen {
description
"The listen feature indicates that the server supports
opening a port to listen for incoming client connections.";
reference
"RFC 6242: Using the NETCONF Protocol over Secure Shell (SSH)
RFC 5539: NETCONF over Transport Layer Security (TLS)";
}
feature call-home {
description
"The call-home feature indicates that the server supports
connecting to the client";
reference
"RFC YYYY: NETCONF Call Home and RESTCONF Call Home";
}
feature rfc6187 {
description
"The rfc6187 feature indicates that the NETCONF server supports
RFC 6187";
reference
"RFC 6187: X.509v3 Certificates for Secure Shell Authentication";
}
// top-level container (groupings below)
container netconf-server {
description
"Top-level container for NETCONF server configuration.";
uses session-options-container;
uses listen-container;
uses call-home-container;
uses ssh-container;
uses tls-container;
}
grouping session-options-container {
description
"";
container session-options {
description
"NETCONF session options, independent of transport or
connection strategy.";
if-feature session-options;
leaf hello-timeout {
type uint32 {
range "0 | 10 .. 3600";
}
units "seconds";
default '600';
description
"Specifies the number of seconds that a session may exist
before the hello PDU is received. A session will be
dropped if no hello PDU is received before this number
of seconds elapses.
If this parameter is set to zero, then the server will
wait forever for a hello message, and not drop any
sessions stuck in 'hello-wait' state.
Setting this parameter to zero may permit denial of
service attacks, since only a limited number of
concurrent sessions may be supported by the server.";
}
leaf idle-timeout {
type uint32 {
range "0 | 10 .. 360000";
}
units "seconds";
default '3600';
description
"Specifies the number of seconds that a NETCONF session may
remain idle without issuing any RPC requests. A session
will be dropped if it is idle for an interval longer than
this number of seconds. If this parameter is set to zero,
then the server will never drop a session because it is
idle. Sessions that have a notification subscription
active are never dropped.
This mechanism is independent of keep-alives, as it regards
activity occurring at the NETCONF protocol layer, whereas
the keep-alive mechanism regards transport-level activity.";
}
}
}
grouping listen-container {
description
"";
container listen {
description
"Configures listen behavior";
if-feature listen;
leaf max-sessions {
type uint16 {
range "0 .. 1024";
}
default '0';
description
"Specifies the maximum number of concurrent sessions
that can be active at one time. The value 0 indicates
that no artificial session limit should be used.";
}
list endpoint {
key name;
description
"List of endpoints to listen for connections on.";
leaf name {
type string;
description
"An arbitrary name for the listen endpoint.";
}
choice transport {
mandatory true;
description
"Selects between SSH and TLS transports.";
case ssh {
if-feature ssh;
container ssh {
description
"SSH-specific listening configuration for inbound
connections.";
uses address-and-port-grouping {
refine port {
default 830;
}
}
uses host-keys-container;
}
}
case tls {
if-feature tls;
container tls {
description
"TLS-specific listening configuration for inbound
connections.";
uses address-and-port-grouping {
refine port {
default 6513;
}
}
uses certificates-container;
}
}
}
uses keep-alives-container {
refine keep-alives/interval-secs {
default 0; // disabled by default for listen connections
}
}
}
}
}
grouping call-home-container {
description
"";
container call-home {
if-feature call-home;
description
"Configures call-home behavior";
list application {
key name;
description
"List of NETCONF clients the NETCONF server is to initiate
call-home connections to.";
leaf name {
type string;
description
"An arbitrary name for the remote NETCONF client.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case ssh {
if-feature ssh;
container ssh {
description
"Specifies SSH-specific call-home transport
configuration.";
uses endpoints-container {
refine endpoints/endpoint/port {
default 7777;
}
}
uses host-keys-container;
}
}
case tls {
if-feature tls;
container tls {
description
"Specifies TLS-specific call-home transport
configuration.";
uses endpoints-container {
refine endpoints/endpoint/port {
default 8888;
}
}
uses certificates-container;
}
}
}
container connection-type {
description
"Indicates the kind of connection to be maintained.";
choice connection-type {
default persistent-connection;
description
"Selects between persistent and periodic connections.";
case persistent-connection {
container persistent {
description
"Maintain a persistent connection to the NETCONF
client. If the connection goes down, immediately
start trying to reconnect to it, using the
reconnection strategy.
This connection type minimizes any NETCONF client
to NETCONF server data-transfer delay, albeit at
the expense of holding resources longer.";
uses keep-alives-container {
refine keep-alives/interval-secs {
default 15; // 15 seconds for call-home sessions
}
}
}
}
case periodic-connection {
container periodic {
description
"Periodically connect to NETCONF client, using the
reconnection strategy, so the NETCONF client can
deliver pending messages to the NETCONF server.
For messages the NETCONF server wants to send to
to the NETCONF client, the NETCONF server should
proactively connect to the NETCONF client, if
not already, to send the messages immediately.";
leaf timeout-mins {
type uint8;
units minutes;
default 5;
description
"The maximum amount of unconnected time the NETCONF
server will wait until establishing a connection to
the NETCONF client again. The NETCONF server MAY
establish a connection before this time if it has
data it needs to send to the NETCONF client. Note:
this value differs from the reconnection strategy's
interval-secs value.";
}
leaf linger-secs {
type uint8;
units seconds;
default 30;
description
"The amount of time the NETCONF server should wait
after last receiving data from or sending data to
the NETCONF client's endpoint before closing its
connection to it. This is an optimization to
prevent unnecessary connections.";
}
}
}
}
}
container reconnect-strategy {
description
"The reconnection strategy guides how a NETCONF server
reconnects to an NETCONF client, after losing a connection
to it, even if due to a reboot. The NETCONF server starts
with the specified endpoint and tries to connect to it
count-max times, waiting interval-secs between each
connection attempt, before trying the next endpoint in
the list (round robin).";
leaf start-with {
type enumeration {
enum first-listed {
description
"Indicates that reconnections should start with
the first endpoint listed.";
}
enum last-connected {
description
"Indicates that reconnections should start with
the endpoint last connected to. NETCONF servers
SHOULD support this flag across reboots.";
}
}
default first-listed;
description
"Specifies which of the NETCONF client's endpoints the
NETCONF server should start with when trying to connect
to the NETCONF client. If no previous connection has
ever been established, last-connected defaults to
the first endpoint listed.";
}
leaf interval-secs {
type uint8;
units seconds;
default 5;
description
"Specifies the time delay between connection attempts
to the same endpoint. Note: this value differs from
the periodic-connection's timeout-mins value.";
}
leaf count-max {
type uint8;
default 3;
description
"Specifies the number times the NETCONF server tries to
connect to a specific endpoint before moving on to the
next endpoint in the list (round robin).";
}
}
}
}
}
grouping ssh-container {
description
"";
container ssh {
description
"Configures SSH properties not specific to the listen
or call-home use-cases";
if-feature ssh;
container x509 {
if-feature rfc6187;
uses trusted-certs-grouping;
}
}
}
grouping tls-container {
description
"";
container tls {
description
"Configures TLS properties not specific to the listen
or call-home use-cases";
if-feature tls;
container client-auth {
description
"Container for TLS client authentication configuration.";
uses trusted-certs-grouping;
container cert-maps {
uses x509c2n:cert-to-name;
description
"The cert-maps container is used by a NETCONF server to
map the NETCONF client's presented X.509 certificate to a
NETCONF username. If no matching and valid cert-to-name
list entry can be found, then the NETCONF server MUST
close the connection, and MUST NOT accept NETCONF
messages over it.";
}
}
}
}
grouping trusted-certs-grouping {
description
"";
container trusted-ca-certs {
description
"A list of Certificate Authority (CA) certificates that
a NETCONF server can use to authenticate NETCONF client
certificates. A client's certificate is authenticated
if there is a chain of trust to a configured trusted CA
certificate. The client certificate MAY be accompanied
with additional certificates forming a chain of trust.
The client's certificate is authenticated if there is
path-validation from any of the certificates it presents
to a configured trust anchor.";
leaf-list trusted-ca-cert {
type binary;
ordered-by system;
description
"The binary certificate structure as specified by RFC
5246, Section 7.4.6, i.e.,: opaque ASN.1Cert<1..2^24>;
";
reference
"RFC 5246: The Transport Layer Security (TLS)
Protocol Version 1.2";
}
}
container trusted-client-certs {
description
"A list of client certificates that a NETCONF server can
use to authenticate a NETCONF client's certificate. A
client's certificate is authenticated if it is an exact
match to a configured trusted client certificates.";
leaf-list trusted-client-cert {
type binary;
ordered-by system;
description
"The binary certificate structure, as
specified by RFC 5246, Section 7.4.6, i.e.,:
opaque ASN.1Cert<1..2^24>;
";
reference
"RFC 5246: The Transport Layer Security (TLS)
Protocol Version 1.2";
}
}
}
grouping host-keys-container {
description
"";
container host-keys {
description
"Parent container for the list of host-keys.";
leaf-list host-key {
type string;
min-elements 1;
ordered-by user;
description
"A user-ordered list of host-keys the SSH server
considers when composing the list of server host
key algorithms it will send to the client in its
SSH_MSG_KEXINIT message. The value of the string
is the unique identifier for a host-key configured
on the system. How valid values are discovered is
outside the scope of this module, but they are
envisioned to be the keys for a list of host-keys
provided by another YANG module";
reference
"RFC 4253: The SSH Transport Layer Protocol, Section 7";
}
}
}
grouping certificates-container {
description
"";
container certificates {
description
"Parent container for the list of certificates.";
leaf-list certificate {
type string;
min-elements 1;
description
"An unordered list of certificates the TLS server can pick
from when sending its Server Certificate message. The value
of the string is the unique identifier for a certificate
configured on the system. How valid values are discovered
is outside the scope of this module, but they are envisioned
to be the keys for a list of certificates provided
by another YANG module";
reference
"RFC 5246: The TLS Protocol, Section 7.4.2";
}
}
}
grouping address-and-port-grouping {
description
"a common grouping";
leaf address {
type inet:ip-address;
description
"The IP address of the interface to listen on.";
}
leaf port {
type inet:port-number;
description
"The local port number on this interface the NETCONF server
listens on.";
}
}
grouping endpoints-container {
description
"Grouping for transport-specific configuration for
call-home connections.";
container endpoints {
description
"Container for the list of endpoints.";
list endpoint {
key name;
min-elements 1;
ordered-by user;
description
"User-ordered list of endpoints for this NETCONF client.
Defining more than one enables high-availability.";
leaf name {
type string;
description
"An arbitrary name for the endpoint to connect to.";
}
leaf address {
type inet:host;
mandatory true;
description
"The hostname or IP address or hostname of the endpoint.
If a hostname is provided and DNS resolves to more than
one IP address, the NETCONF server SHOULD try all of
the ones it can based on how its networking stack is
configured (e.g. v4, v6, dual-stack).";
}
leaf port {
type inet:port-number;
description
"The IP port for this endpoint. The NETCONF server will
use the IANA-assigned well-known port if not specified.";
}
}
}
}
grouping keep-alives-container {
description
"";
container keep-alives {
description
"Configures the keep-alive policy, to proactively test the
aliveness of the NETCONF client, in order to know when a
new call home connection should be established.";
reference
"RFC VVVV: NETCONF Server and RESTCONF Server Configuration
Models, Section 4";
leaf interval-secs {
type uint8;
units seconds;
description
"Sets a timeout interval in seconds after which if no data
has been received from the NETCONF client, a message will
be sent to request a response from the NETCONF client. A
value of '0' indicates that no keep-alive messages should
be sent.";
}
leaf count-max {
type uint8;
default 3;
description
"Sets the number of keep-alive messages that may be sent
without receiving any data from the NETCONF client before
assuming the NETCONF client is no longer alive. If this
threshold is reached, the transport-level connection will
be disconnected, which will trigger the reconnection
strategy). The interval timer is reset after each
transmission, thus an unresponsive NETCONF client will
be dropped after ~count-max * interval-secs seconds.";
}
}
}
}
<CODE ENDS>
]]></artwork>
</figure>
</t>
</section>
</section>
<section title="The RESTCONF Server Configuration Model">
<section title="Overview">
<section title="The "listen" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-restconf-server
+--rw restconf-server
+--rw listen {listen}?
+--rw max-sessions? uint16
+--rw endpoint* [name]
+--rw name string
+--rw (transport)
| +--:(tls)
| +--rw tls
| +--rw address? inet:ip-address
| +--rw port? inet:port-number
| +--rw certificates
| +--rw certificate* string
+--rw keep-alives
+--rw interval-secs? uint8
+--rw count-max? uint8
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-restconf-server YANG module
enables configuration for listening for remote connections,
as described in <xref target="draft-ietf-netconf-restconf"/> and <xref
target="draft-ietf-netconf-call-home"/>. Feature statements are used to limit both
if listening is supported at all as well as for which transports.
If listening for connections is supported, then the model
enables configuring a list of listening endpoints, each
configured with a
user-specified name (the key field), the transport to use
(i.e. SSH, TLS), and the IP address and port to listen on.
The port field is optional, defaulting to the transport-specific
port when not configured.
Please see the YANG module (<xref target="restconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
<section title="The "call-home" subtree">
<t>
<figure>
<artwork><![CDATA[
module: ietf-restconf-server
+--rw restconf-server
+--rw call-home {call-home}?
+--rw application* [name]
+--rw name string
+--rw (transport)
| +--:(tls) {tls}?
| +--rw tls
| +--rw endpoints
| | +--rw endpoint* [name]
| | +--rw name string
| | +--rw address inet:host
| | +--rw port? inet:port-number
| +--rw certificates
| +--rw certificate* string
+--rw connection-type
| +--rw (connection-type)?
| +--:(persistent-connection)
| | +--rw persistent
| | +--rw keep-alives
| | +--rw interval-secs? uint8
| | +--rw count-max? uint8
| +--:(periodic-connection)
| +--rw periodic
| +--rw timeout-mins? uint8
| +--rw linger-secs? uint8
+--rw reconnect-strategy
+--rw start-with? enumeration
+--rw interval-secs? uint8
+--rw count-max? uint8
]]></artwork>
</figure>
</t>
<t>The above subtree illustrates how the ietf-restconf-server YANG module
enables configuration for call home, as described in
<xref target="draft-ietf-netconf-call-home"/>. Feature
statements are used to limit both if call-home is supported
at all as well as for which transports, if it is. If call-home
is supported, then the model supports configuring a list of
applications to connect to. Each application is configured
with a user-specified name (the key field), the transport to
be used (i.e. SSH, TLS), and a list of remote endpoints, each
having a name, an IP address, and an optional port. Additionally,
the configuration for each remote application indicates the
connection-type (persistent vs. periodic) and associated
parameters, as well as the reconnection strategy to use.
Please see the YANG module (<xref target="restconf-yang-module"/>)
for a complete description of these configuration knobs.</t>
</section>
</section>
<section title="YANG Module" anchor="restconf-yang-module">
<t>This YANG module imports YANG types from <xref target="RFC6991"/>.</t>
<t>
<figure>
<artwork><![CDATA[
<CODE BEGINS> file "ietf-restconf-server@2014-12-11.yang"
module ietf-restconf-server {
namespace "urn:ietf:params:xml:ns:yang:ietf-restconf-server";
prefix "rcserver";
import ietf-inet-types { // RFC 6991
prefix inet;
revision-date 2013-07-15;
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
WG Chair: Mehmet Ersue
<mailto:mehmet.ersue@nsn.com>
WG Chair: Mahesh Jethanandani
<mailto:mjethanandani@gmail.com>
Editor: Kent Watsen
<mailto:kwatsen@juniper.net>";
description
"This module contains a collection of YANG definitions for
configuring RESTCONF servers.
Copyright (c) 2014 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 VVVV; see
the RFC itself for full legal notices.";
revision "2014-12-11" {
description
"Initial version";
reference
"RFC VVVV: NETCONF Server and RESTCONF Server Configuration Models";
}
// Features
feature tls {
description
"The tls feature indicates that the server supports RESTCONF
over the TLS transport protocol.";
reference
"RFC XXXX: RESTCONF Protocol";
}
feature listen {
description
"The listen feature indicates that the server supports
opening a port to listen for incoming client connections.";
reference
"RFC XXXX: RESTCONF Protocol";
}
feature call-home {
description
"The call-home feature indicates that the server supports
connecting to the client";
reference
"RFC YYYY: NETCONF Call Home and RESTCONF Call Home";
}
// top-level container (groupings below)
container restconf-server {
description
"Top-level container for RESTCONF server configuration.";
uses listen-container;
uses call-home-container;
}
grouping listen-container {
description
"";
container listen {
description
"Configures listen behavior";
if-feature listen;
leaf max-sessions {
type uint16 {
range "0 .. 1024";
}
default '0';
description
"Specifies the maximum number of concurrent sessions
that can be active at one time. The value 0 indicates
that no artificial session limit should be used.";
}
list endpoint {
key name;
description
"List of endpoints to listen for connections on.";
leaf name {
type string;
description
"An arbitrary name for the listen endpoint.";
}
choice transport {
mandatory true;
description
"Selects between available transports.";
case tls {
container tls {
description
"TLS-specific listening configuration for inbound
connections.";
uses address-and-port-grouping {
refine port {
default 6513;
}
}
uses certificates-container;
}
}
}
uses keep-alives-container {
refine keep-alives/interval-secs {
default 0; // disabled by default for listen connections
}
}
}
}
}
grouping call-home-container {
description
"";
container call-home {
if-feature call-home;
description
"Configures call-home behavior";
list application {
key name;
description
"List of RESTCONF clients the RESTCONF server is to initiate
call-home connections to.";
leaf name {
type string;
description
"An arbitrary name for the remote RESTCONF client.";
}
choice transport {
mandatory true;
description
"Selects between SSH and TLS transports.";
case tls {
if-feature tls;
container tls {
description
"Specifies TLS-specific call-home transport
configuration.";
uses endpoints-container {
refine endpoints/endpoint/port {
default 9999;
}
}
uses certificates-container;
}
}
}
container connection-type {
description
"Indicates the RESTCONF client's preference for how the
RESTCONF server's connection is maintained.";
choice connection-type {
default persistent-connection;
description
"Selects between persistent and periodic connections.";
case persistent-connection {
container persistent {
description
"Maintain a persistent connection to the RESTCONF
client. If the connection goes down, immediately
start trying to reconnect to it, using the
reconnection strategy.
This connection type minimizes any RESTCONF client
to RESTCONF server data-transfer delay, albeit at
the expense of holding resources longer.";
uses keep-alives-container {
refine keep-alives/interval-secs {
default 15; // 15 seconds for call-home sessions
}
}
}
}
case periodic-connection {
container periodic {
description
"Periodically connect to RESTCONF client, using the
reconnection strategy, so the RESTCONF client can
deliver pending messages to the RESTCONF server.
For messages the RESTCONF server wants to send to
to the RESTCONF client, the RESTCONF server should
proactively connect to the RESTCONF client, if
not already, to send the messages immediately.";
leaf timeout-mins {
type uint8;
units minutes;
default 5;
description
"The maximum amount of unconnected time the RESTCONF
server will wait until establishing a connection to
the RESTCONF client again. The RESTCONF server MAY
establish a connection before this time if it has
data it needs to send to the RESTCONF client. Note:
this value differs from the reconnection strategy's
interval-secs value.";
}
leaf linger-secs {
type uint8;
units seconds;
default 30;
description
"The amount of time the RESTCONF server should wait
after last receiving data from or sending data to
the RESTCONF client's endpoint before closing its
connection to it. This is an optimization to
prevent unnecessary connections.";
}
}
}
}
}
container reconnect-strategy {
description
"The reconnection strategy guides how a RESTCONF server
reconnects to an RESTCONF client, after losing a connection
to it, even if due to a reboot. The RESTCONF server starts
with the specified endpoint and tries to connect to it
count-max times, waiting interval-secs between each
connection attempt, before trying the next endpoint in
the list (round robin).";
leaf start-with {
type enumeration {
enum first-listed {
description
"Indicates that reconnections should start with
the first endpoint listed.";
}
enum last-connected {
description
"Indicates that reconnections should start with
the endpoint last connected to. RESTCONF servers
SHOULD support this flag across reboots.";
}
}
default first-listed;
description
"Specifies which of the RESTCONF client's endpoints the
RESTCONF server should start with when trying to connect
to the RESTCONF client. If no previous connection has
ever been established, last-connected defaults to
the first endpoint listed.";
}
leaf interval-secs {
type uint8;
units seconds;
default 5;
description
"Specifies the time delay between connection attempts
to the same endpoint. Note: this value differs from
the periodic-connection's timeout-mins value.";
}
leaf count-max {
type uint8;
default 3;
description
"Specifies the number times the RESTCONF server tries to
connect to a specific endpoint before moving on to the
next endpoint in the list (round robin).";
}
}
}
}
}
grouping certificates-container {
description
"";
container certificates {
description
"Parent container for the list of certificates.";
leaf-list certificate {
type string;
min-elements 1;
description
"An unordered list of certificates the TLS server can pick
from when sending its Server Certificate message. The value
of the string is the unique identifier for a certificate
configured on the system. How valid values are discovered
is outside the scope of this module, but they are envisioned
to be the keys for a list of certificates provided
by another YANG module";
reference
"RFC 5246: The TLS Protocol, Section 7.4.2";
}
}
}
grouping address-and-port-grouping {
description
"a common grouping";
leaf address {
type inet:ip-address;
description
"The IP address of the interface to listen on.";
}
leaf port {
type inet:port-number;
description
"The local port number on this interface the RESTCONF server
listens on.";
}
}
grouping endpoints-container {
description
"Grouping for transport-specific configuration for
call-home connections.";
container endpoints {
description
"Container for the list of endpoints.";
list endpoint {
key name;
min-elements 1;
ordered-by user;
description
"User-ordered list of endpoints for this RESTCONF client.
Defining more than one enables high-availability.";
leaf name {
type string;
description
"An arbitrary name for the endpoint to connect to.";
}
leaf address {
type inet:host;
mandatory true;
description
"The hostname or IP address or hostname of the endpoint.
If a hostname is provided and DNS resolves to more than
one IP address, the RESTCONF server SHOULD try all of
the ones it can based on how its networking stack is
configured (e.g. v4, v6, dual-stack).";
}
leaf port {
type inet:port-number;
description
"The IP port for this endpoint. The RESTCONF server will
use the IANA-assigned well-known port if not specified.";
}
}
}
}
grouping keep-alives-container {
description
"";
container keep-alives {
description
"Configures the keep-alive policy, to proactively test the
aliveness of the RESTCONF client, in order to know when a
new call home connection should be established.";
reference
"RFC VVVV: NETCONF Server and RESTCONF Server Configuration
Models, Section 4";
leaf interval-secs {
type uint8;
units seconds;
description
"Sets a timeout interval in seconds after which if no data
has been received from the RESTCONF client, a message will
be sent to request a response from the RESTCONF client. A
value of '0' indicates that no keep-alive messages should
be sent.";
}
leaf count-max {
type uint8;
default 3;
description
"Sets the number of keep-alive messages that may be sent
without receiving any data from the RESTCONF client before
assuming the RESTCONF client is no longer alive. If this
threshold is reached, the transport-level connection will
be disconnected, which will trigger the reconnection
strategy). The interval timer is reset after each
transmission, thus an unresponsive RESTCONF client will
be dropped after ~count-max * interval-secs seconds.";
}
}
}
}
<CODE ENDS>
]]></artwork>
</figure>
</t>
</section>
</section>
<section title="Implementation strategy for keep-alives">
<t>One of the objectives listed above, Keep-alives for persistent
connections <xref target="keepalives"/>, indicates a need
for a "keep-alive" mechanism. This section specifies how the
keep-alive mechanism is to be implemented for both the
SSH and TLS transports.</t>
<t>Both SSH and TLS have the ability to support keep-alives securely.
Using the strategies listed below, the keep-alive messages are sent
inside the encrypted tunnel and thus immune to attack.</t>
<section title="Keep-alives for SSH">
<t>The SSH keep-alive solution that is expected to be used
is ubiquitous in practice, though never being explicitly defined
in an RFC. The strategy used is to purposely send a malformed
request message with a flag set to ensure a response. More
specifically, per section 4 of <xref target="RFC4253"/>, either
SSH peer can send a SSH_MSG_GLOBAL_REQUEST message with "want
reply" set to '1' and that, if there is an error, will get back
a SSH_MSG_REQUEST_FAILURE response. Similarly, section 5 of
<xref target="RFC4253"/> says that either SSH peer can send a
SSH_MSG_CHANNEL_REQUEST message with "want reply" set to '1'
and that, if there is an error, will get back a
SSH_MSG_CHANNEL_FAILURE response.</t>
<t>To ensure that the request will fail, current implementations
of this keep-alive strategy (e.g. OpenSSH's `sshd` server) send an
invalid "request name" or "request type", respectively. Abiding
to the extensibility guidelines specified in Section 6
of <xref target="RFC4251"/>, these implementations use the
"name@domain". For instance, when configured to send keep-alives,
OpenSSH sends the string "keepalive@openssh.com". In order to
remain compatible with existing implementations, this draft does
not require a specific "request name" or "request type" string
be used, implementations are free to pick values of their choosing.</t>
</section>
<section title="Keep-alives for TLS">
<t>The TLS keep-alive solution that is expected to be used is
defined in <xref target="RFC6520"/>.
This solution allows both peers to advertise if they can
receive heartbeat request messages from its peer.
For standard TLS connections, devices SHOULD
advertise "peer_allowed_to_send", as per <xref target="RFC6520"/>.
This advertisement is not a "MUST" in order to grandfather
existing NETCONF/RESTCONF over TLS implementations.
For NETCONF Call Home or RESTCONF Call Home, the network management
system MUST advertise "peer_allowed_to_send" per
<xref target="RFC6520"/>. This is a "MUST" so as to ensure
devices can depend on it always being there for call home
connections, which is when keep-alives are needed the most.</t>
</section>
</section>
<section title="Security Considerations">
<t>The YANG modules defined in this memo are designed to be
accessed via the NETCONF protocol <xref target="RFC6241"/>.
Authorization for access to specific portions of conceptual
data and operations within this module is provided by the
NETCONF access control model (NACM) <xref target="RFC6536"/>.</t>
<t>There are a number of data nodes defined in the
"ietf-netconf-server" YANG module which are readable and/or
writable that may be considered sensitive or vulnerable in some
network environments. Write and read operations to
these data nodes can have a negative effect on network
operations. It is thus important to control write
and read access to these data nodes. Below are the
data nodes and their sensitivity/vulnerability.</t>
<t>netconf-server/tls/client-auth/trusted-ca-certs:
<list style="symbols">
<t>This container contains certificates that the server
is to use as trust anchors for authenticating TLS-specific
client certificates. Write access to this node should be
protected.</t>
</list>
</t>
<t>netconf-server/tls/client-auth/trusted-client-certs:
<list style="symbols">
<t>This container contains certificates that the server
is to trust directly when authenticating TLS-specific
client certificates. Write access to this node should be
protected.</t>
</list>
</t>
<t>netconf-server/tls/client-auth/cert-map:
<list style="symbols">
<t>This container contains a user name that some deployments
may consider sensitive information. Read access to this
node may need to be guarded.</t>
</list>
</t>
</section>
<section title="IANA Considerations">
<t>This document registers two URIs in the IETF XML
registry <xref target="RFC2119"/>. Following the format in
<xref target="RFC3688"/>, the following registrations are
requested:</t>
<t>
<figure>
<artwork><![CDATA[
URI: urn:ietf:params:xml:ns:yang:ietf-netconf-server
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-restconf-server
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
]]></artwork>
</figure>
</t>
<t>This document registers two YANG modules in the
YANG Module Names registry <xref target="RFC6020"/>.
Following the format in <xref target="RFC6020"/>, the
the following registrations are requested:</t>
<t>
<figure>
<artwork><![CDATA[
name: ietf-netconf-server
namespace: urn:ietf:params:xml:ns:yang:ietf-netconf-server
prefix: ncserver
reference: RFC VVVV
name: ietf-restconf-server
namespace: urn:ietf:params:xml:ns:yang:ietf-restconf-server
prefix: rcserver
reference: RFC VVVV
]]></artwork>
</figure>
</t>
</section>
<section title="Other Considerations">
<t>The YANG modules define herein do not themselves support
virtual routing and forwarding (VRF). It is expected that
external modules will augment in VRF designations when needed.</t>
</section>
<section title="Acknowledgements">
<t>The authors would like to thank for following for
lively discussions on list and in the halls (ordered
by last name): Andy Bierman, Martin Bjorklund, Benoit Claise,
Mehmet Ersue, David Lamparter, Alan Luchuk, Ladislav Lhotka,
Radek Krejci, Tom Petch, Phil Shafer, and Bert Wijnen.</t>
<t>
Juergen Schoenwaelder and was partly funded by Flamingo, a
Network of Excellence project (ICT-318488) supported by the
European Commission under its Seventh Framework Programme.
</t>
</section>
</middle>
<back>
<references title="Normative References">
&rfc2119;
&rfc4251;
&rfc4253;
&rfc6020;
&rfc6187;
&rfc6241;
&rfc6242;
&rfc6520;
&rfc6536;
&rfc6991;
<reference anchor='draft-ietf-netconf-rfc5539bis'>
<front>
<title>
Using the NETCONF Protocol over Transport Layer
Security (TLS)
</title>
<author initials='M' surname='Badra'
fullname='Mohamad Badra'>
<organization>LIMOS Laboratory</organization>
</author>
<author initials='A' surname='Luchuk'
fullname='Alan Luchuk'>
<organization>SNMP Research, Inc.</organization>
</author>
<author initials='J' surname='Schönwälder'
fullname='Jürgen Schönwälder'>
<organization>Jacobs University</organization>
</author>
<date year='2014' />
</front>
<seriesInfo name='Internet-Draft'
value='draft-ietf-netconf-rfc5539bis-06' />
</reference>
<reference anchor='draft-ietf-netmod-snmp-cfg'>
<front>
<title>A YANG Data Model for SNMP Configuration</title>
<author initials='M' surname='Bjorklund'
fullname='Martin Bjorklund'>
<organization>Tail-f Systems</organization>
</author>
<author initials='J' surname='Schönwälder'
fullname='Jürgen Schönwälder'>
<organization>Jacobs University</organization>
</author>
<date month='September' day='18' year='2014' />
</front>
<seriesInfo name='Internet-Draft' value='draft-ietf-netmod-snmp-cfg-08' />
</reference>
<reference anchor='draft-ietf-netconf-call-home'>
<front>
<title>
NETCONF Call Home and RESTCONF Call Home
</title>
<author initials='K.W.' surname='Watsen'
fullname='Kent Watsen'>
<organization>Juniper Networks</organization>
</author>
<date year='2014' />
</front>
<seriesInfo name='Internet-Draft'
value='draft-ieft-netconf-call-home-02' />
</reference>
<reference anchor='draft-ietf-netconf-restconf'>
<front>
<title>RESTCONF Protocol</title>
<author initials='A.B.' surname='Bierman'
fullname='Andy Bierman'>
<organization>YumaWorks</organization>
</author>
<author initials='M' surname='Bjorklund'
fullname='Martin Bjorklund'>
<organization>Tail-f Systems</organization>
</author>
<author initials='K.W.' surname='Watsen'
fullname='Kent Watsen'>
<organization>Juniper Networks</organization>
</author>
<date year='2014' />
</front>
<seriesInfo name='Internet-Draft'
value='draft-ieft-netconf-restconf-04' />
</reference>
</references>
<references title="Informative References">
<reference anchor="RFC3688">
<front>
<title>The IETF XML Registry</title>
<author initials="M.M." surname="Mealling"
fullname="Michael Mealling">
<organization>VeriSign Inc.</organization>
</author>
<date month="January" year="2004" />
</front>
<seriesInfo name="BCP" value="81" />
<seriesInfo name="RFC" value="3688"/>
</reference>
</references>
<section title="Examples">
<section title="NETCONF Configuration using SSH Transport">
<t>
The following example illustrates the <get> response from a NETCONF server
that only supports SSH, both listening for incoming connections as well as
calling home to a single application having two endpoints.
</t>
<t>
<figure>
<artwork><![CDATA[
<netconf-server xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server">
<session-options>
<hello-timeout>600</hello-timeout>
<idle-timeout>3600</idle-timeout>
</session-options>
<listen>
<endpoint>
<name>foo bar</name>
<ssh>
<address>11.22.33.44</address>
<host-keys>
<host-key>my-rsa-key</host-key>
<host-key>my-dss-key</host-key>
</host-keys>
</ssh>
</endpoint>
</listen>
<call-home>
<application>
<name>config-mgr</name>
<ssh>
<endpoints>
<endpoint>
<name>east-data-center</name>
<address>11.22.33.44</address>
</endpoint>
<endpoint>
<name>west-data-center</name>
<address>55.66.77.88</address>
</endpoint>
</endpoints>
<host-keys>
<host-key>my-call-home-x509-key</host-key>
</host-keys>
</ssh>
</application>
</call-home>
<ssh>
<x509>
<trusted-ca-certs>
<trusted-ca-cert>
QW4gRWFzdGVyIGVnZywgZm9yIHRob3NlIHdobyBtaWdodCBsb29rICA6KQo=
</trusted-ca-cert>
</trusted-ca-certs>
<trusted-client-certs>
<trusted-client-cert>
SSBhbSB0aGUgZWdnIG1hbiwgdGhleSBhcmUgdGhlIGVnZyBtZW4uCg==
</trusted-client-cert>
<trusted-client-cert>
SSBhbSB0aGUgd2FscnVzLCBnb28gZ29vIGcnam9vYi4K
</trusted-client-cert>
</trusted-client-certs>
</x509>
</ssh>
</netconf-server>
]]></artwork>
</figure>
</t>
</section>
<section title="NETCONF Configuration using TLS Transport">
<t>
The following example illustrates the <get> response from a NETCONF server
that only supports TLS, both listening for incoming connections as well as
calling home to a single application having two endpoints. Please note also
the configurations for authenticating client certificates and mappings
authenticated certificates to NETCONF user names.
</t>
<t>
<figure>
<artwork><![CDATA[
<netconf-server xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server">
<session-options>
<hello-timeout>600</hello-timeout>
<idle-timeout>3600</idle-timeout>
</session-options>
<listen>
<endpoint>
<name>primary-netconf-endpoint</name>
<tls>
<address>11.22.33.44</address>
<certificates>
<certificate>fw1.east.example.com</certificate>
</certificates>
</tls>
</endpoint>
</listen>
<call-home>
<application>
<name>config-mgr</name>
<tls>
<endpoints>
<endpoint>
<name>east-data-center</name>
<address>11.22.33.44</address>
</endpoint>
<endpoint>
<name>west-data-center</name>
<address>55.66.77.88</address>
</endpoint>
</endpoints>
<certificates>
<certificate>fw1.east.example.com</certificate>
</certificates>
</tls>
</application>
</call-home>
<tls>
<client-auth>
<trusted-ca-certs>
<trusted-ca-cert>
QW4gRWFzdGVyIGVnZywgZm9yIHRob3NlIHdobyBtaWdodCBsb29rICA6KQo=
</trusted-ca-cert>
</trusted-ca-certs>
<trusted-client-certs>
<trusted-client-cert>
SSBhbSB0aGUgZWdnIG1hbiwgdGhleSBhcmUgdGhlIGVnZyBtZW4uCg==
</trusted-client-cert>
<trusted-client-cert>
SSBhbSB0aGUgd2FscnVzLCBnb28gZ29vIGcnam9vYi4K
</trusted-client-cert>
</trusted-client-certs>
<cert-maps>
<cert-to-name>
<id>1</id>
<fingerprint>11:0A:05:11:00</fingerprint>
<map-type>x509c2n:san-any</map-type>
</cert-to-name>
<cert-to-name>
<id>2</id>
<fingerprint>11:0A:05:11:00</fingerprint>
<map-type>x509c2n:specified</map-type>
<name>Joe Cool</name>
</cert-to-name>
</cert-maps>
</client-auth>
</tls>
</netconf-server>
]]></artwork>
</figure>
</t>
</section>
<section title="RESTCONF Configuration using TLS Transport">
<t>
The following example illustrates the <get> response from a RESTCONF server
that only supports TLS, both listening for incoming connections as well as
calling home to a single application having two endpoints.
</t>
<t>
<figure>
<artwork><![CDATA[
<restconf-server xmlns="urn:ietf:params:xml:ns:yang:ietf-restconf-server">
<listen>
<endpoint>
<name>primary-restconf-endpoint</name>
<tls>
<address>11.22.33.44</address>
<certificates>
<certificate>fw1.east.example.com</certificate>
</certificates>
</tls>
</endpoint>
</listen>
<call-home>
<application>
<name>config-mgr</name>
<tls>
<endpoints>
<endpoint>
<name>east-data-center</name>
<address>11.22.33.44</address>
</endpoint>
<endpoint>
<name>west-data-center</name>
<address>55.66.77.88</address>
</endpoint>
</endpoints>
<certificates>
<certificate>fw1.east.example.com</certificate>
</certificates>
</tls>
</application>
</call-home>
</restconf-server>
]]></artwork>
</figure>
</t>
</section>
</section>
<section title="Change Log">
<section title="00 to 01">
<t>
<list style="symbols">
<t>Restructured document so it flows better</t>
<t>Added trusted-ca-certs and trusted-client-certs
objects into the ietf-system-tls-auth module</t>
</list>
</t>
</section>
<section title="01 to 02">
<t>
<list style="symbols">
<t>removed the "one-to-many" construct</t>
<t>removed "address" as a key field</t>
<t>removed "network-manager" terminology</t>
<t>moved open issues to github issues</t>
<t>brought TLS client auth back into model</t>
</list>
</t>
</section>
<section title="02 to 03">
<t>
<list style="symbols">
<t>fixed tree diagrams and surrounding text</t>
</list>
</t>
</section>
<section title="03 to 04">
<t>
<list style="symbols">
<t>reduced the number of grouping statements</t>
<t>removed psk-maps and associated feature statements</t>
<t>added ability for listen/call-home instances to specify
which host-keys/certificates (of all listed) to use</t>
<t>clarified that last-connected should span reboots</t>
<t>added missing "objectives" for selecting which keys to use,
authenticating client-certificates, and mapping authenticated
client-certificates to usernames</t>
<t>clarified indirect client certificate authentication</t>
<t>added keep-alive configuration for listen connections</t>
<t>added global-level NETCONF session parameters</t>
</list>
</t>
</section>
<section title="04 to 05">
<t>
<list style="symbols">
<t>Removed all refs to the old ietf-system-tls-auth module</t>
<t>Removed YANG 1.1 style if-feature statements (loss some expressiveness)</t>
<t>Removed the read-only (config false) lists of SSH host-keys and TLS certs</t>
<t>Added an if-feature around session-options container</t>
<t>Added ability to configure trust-anchors for SSH X.509 client certs</t>
<t>Now imports by revision, per best practice</t>
<t>Added support for RESTCONF server</t>
<t>Added RFC Editor instructions</t>
</list>
</t>
</section>
</section>
<section title="Open Issues">
<t>Please see: https://github.com/netconf-wg/server-model/issues.</t>
</section>
</back>
</rfc>
| PAFTECH AB 2003-2026 | 2026-04-22 04:56:34 |