| NETCONF | A. Gonzalez Prieto |
| Internet-Draft | VMware |
| Intended status: Standards Track | A. Clemm |
| Expires: April 5, 2018 | Huawei |
| E. Voit | |
| E. Nilsen-Nygaard | |
| A. Tripathy | |
| Cisco Systems | |
| October 2, 2017 |
NETCONF Support for Event Notifications
draft-ietf-netconf-netconf-event-notifications-05
This document defines how to transport network subscriptions and event messages on top of the Network Configuration protocol (NETCONF). This includes the full set of RPCs, subscription state changes, and subscribed content needing asynchronous delivery.
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This Internet-Draft will expire on April 5, 2018.
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This document defines mechanisms that provide a subscription and asynchronous message notification delivery service for the NETCONF protocol [RFC6241] based on [subscribe]. This is an optional capability built on top of the base NETCONF definition.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.
The following terms are defined in [RFC6241]: client, server, operation, RPC.
The following terms are defined in [subscribe]: event, event notification, stream, publisher, receiver, subscriber, subscription, configured subscription.
Note that a publisher in [subscribe] corresponds to a server in [RFC6241]. Similarly, a subscriber corresponds to a client. A receiver is also a client. In the remainder of this document, we will use the terminology in [RFC6241].
In this section, we describe and exemplify how [subscribe] is to be supported over NETCONF.
In the context of [subscribe] an event stream exposes a continuous set of events available for subscription. A NETCONF client can retrieve the list of available event streams from a NETCONF server using the "get" operation against the top-level container "/streams" defined in [subscribe]. The reply includes the list of streams supported on the NETCONF server.
The following example illustrates the retrieval of the list of available event streams using the <get> operation.
<rpc message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<get>
<filter type="subtree">
<streams
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0"/>
</filter>
</get>
</rpc>
Figure 1: Get streams request
The NETCONF server returns a list of event streams available. In this example, the list contains the NETCONF, SNMP, and SYSLOG streams.
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<data>
<streams
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<stream>
<stream>NETCONF</stream>
<description>The NETCONF mandatory event stream</description>
</stream>
<stream>
<stream>SNMP</stream>
<description>The SNMP event stream</description>
</stream>
<stream>
<stream>SYSLOG</stream>
<description>The SYSLOG event stream</description>
<replay-support/>
<replay-log-creation-time>
2015-03-09T19:14:55.233Z</replay-log-creation-time>
</stream>
</streams>
</data>
</rpc-reply>
Figure 2: Get streams response
For [yang-push], a similar get is needed to retrieve available datastore names.
A NETCONF server implementation supporting [subscribe] must support dynamic subscriptions and the "NETCONF" notification event stream. The NETCONF event stream contains all NETCONF XML event information supported by the server.
A NETCONF server implementation supporting [yang-push] must support the "running" datastore.
The dynamic subscription RFC and interactions operation is defined in [subscribe].
An example of interactions over NETCONF transport for one sample subscription is below:
<netconf:rpc netconf:message-id="102"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<establish-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<stream>NETCONF</stream>
<event-filter-type>xpath-event-filter</event-filter-type>
<event-filter-contents xmlns:ex="http://example.com/event/1.0"
select="/ex:event[ex:eventClass='fault' and
(ex:severity='minor' or ex:severity='major'
or ex:severity='critical')]" />
</establish-subscription>
</netconf:rpc>
Figure 3: establish-subscription over NETCONF
If the NETCONF server can satisfy the request, the server sends a positive <subscription-result> element, and the subscription-id of the accepted subscription.
<rpc-reply message-id="102"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
ok
</subscription-result>
<identifier
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
52
</identifier>
</rpc-reply>
Figure 4: Successful establish-subscription
If the NETCONF server cannot satisfy the request, or the client has no authorization to establish the subscription, the server will send a negative <subscription-result> element. For instance:
<rpc-reply message-id="103"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
stream-unavailable
</subscription-result>
</rpc-reply>
Figure 5: Unsuccessful establish subscription
If the client request includes parameters the NETCONF server cannot serve, the negative <subscription-result> may include hints at subscription parameters which would have been accepted. For instance, consider the following subscription from [yang-push], which augments the establish-subscription with some additional parameters, including "period". If the client requests a period which the NETCONF server cannot serve, the back-and-forth exchange may be:
<netconf:rpc message-id="101"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<establish-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<datastore>running</datastore>
<event-filter-type>
subtree</event-filter-type>
<event-filter-contents
xmlns:ex="http://example.com/sample-data/1.0">
select="/ex:foo" />
<dampening-period>10</dampening-period>
<encoding>encode-xml</encoding>
</establish-subscription>
</netconf:rpc>
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
error-insufficient-resources
</subscription-result>
<period-hint
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
2000
</period-hint>
</rpc-reply>
Figure 6: Subscription establishment negotiation
+------------+ +-----------+
| Client | | Server |
+------------+ +-----------+
| |
| Capability Exchange |
|<---------------------------->|
| |
| |
| Establish Subscription |
|----------------------------->|
| RPC Reply: OK, id = 22 |
|<-----------------------------|
| |
| Notification (id 22) |
|<-----------------------------|
| |
| |
| Establish Subscription |
|----------------------------->|
| RPC Reply: OK, id = 23 |
|<-----------------------------|
| |
| |
| Notification (id 22) |
|<-----------------------------|
| Notification (id 23) |
|<-----------------------------|
| |
| |
Figure 7: Multiple subscription establishments over a single NETCONF session
This operation is defined in [subscribe].
The following demonstrates modifying a subscription. Consider a subscription from [yang-push], which augments the establish-subscription with some additional parameters, including "period". A subscription may be established and modified as follows.
<netconf:rpc message-id="101"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<establish-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<datastore xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push">
running</datastore>
<event-filter-type>subtree-event-filter</event-filter-type>
<event-filter-contents
xmlns:ex="http://example.com/sample-data/1.0">
select="/ex:foo" />
<period xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
1000
</period>
</establish-subscription>
</netconf:rpc>
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
ok
</subscription-result>
<identifier
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
1922
</identifier>
</rpc-reply>
<netconf:rpc message-id="102"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<modify-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<identifier>1922</identifier>
<period>100</period>
</modify-subscription>
</netconf:rpc>
Figure 8: Subscription modification
If the NETCONF server can satisfy the request, the server sends a positive <subscription-result> element. This response is like that to an establish-subscription request, but without the subscription identifier.
<rpc-reply message-id="102"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
ok
</subscription-result>
</rpc-reply>
Figure 9: Successful modify subscription
If the NETCONF server cannot satisfy the request, the server sends a negative <subscription-result> element. Its contents and semantics are identical to those in an establish-subscription request. For instance:
<rpc-reply message-id="102"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
period-unsupported
</subscription-result>
<period-hint>500</period-hint>
</rpc-reply>
Figure 10: Unsuccessful modify subscription
+------------+ +-----------+
| Client | | Server |
+------------+ +-----------+
| |
| Capability Exchange |
|<---------------------------->|
| |
| Establish Subscription |
|----------------------------->|
| RPC Reply: OK, id = 22 |
|<-----------------------------|
| |
| Notification (id 22) |
|<-----------------------------|
| |
| Modify Subscription (id 22) |
|----------------------------->|
| RPC Reply: OK |
|<-----------------------------|
| |
| Notification (id 22) |
|<-----------------------------|
| |
Figure 11: Message flow for successful subscription modification
This operation is defined in [subscribe] for events, and enhanced in [yang-push] for datastores.
The following demonstrates deleting a subscription.
<netconf:rpc message-id="101"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<delete-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<identifier>1922</identifier>
</delete-subscription>
</netconf:rpc>
Figure 12: Delete subscription
If the NETCONF server can satisfy the request, the server sends a positive <subscription-result> element. For example:
<rpc-reply message-id="103"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
ok
</subscription-result>
</rpc-reply>
Figure 13: Successful delete subscription
If the NETCONF server cannot satisfy the request, the server sends an <subscription-result> element indicating the deletion was not performed. For example:
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
no-such-subscription
</subscription-result>
</rpc-reply>
Figure 14: Unsuccessful delete subscription
Configured subscriptions are established, modified, and deleted using configuration operations against the top-level subtree of [subscribe] or [yang-push] via configuration interface. This document covers configured subscriptions where the chosen protocol to send the notifications to the receivers is NETCONF.
Configured subscriptions are supported by NETCONF servers using NETCONF Call Home [RFC8071].
Any configuration interface can be used to set a configured subscription that uses NETCONF to push notifications to receivers. Without loss of generality, the examples in this section, use a NETCONF interface to configure the subscriptions
For subscription establishment, a NETCONF client may send:
<rpc message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<running/>
</target>
<subscription-config
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<subscription>
<identifier>
1922
</identifier>
<stream>
foo
</stream>
<receiver>
<address>
1.2.3.4
</address>
<port>
1234
</port>
<protocol>
netconf
</protocol>
</receiver>
</subscription>
</subscription-config>
</edit-config>
</rpc>
Figure 15: Establish configured subscription
if the request is accepted, the server would reply:
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ok/>
</rpc-reply>
Figure 16: Response to a successful configuration subscription establishment
if the request is not accepted because the server cannot serve it, no configuration is changed. Int this case the server may reply:
<rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<subscription-result
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
error-insufficient-resources
</subscription-result>
</rpc-reply>
Figure 17: Response to a failed configured subscription establishment
For every configured receiver, once NETCONF transport session between the server and the receiver is recognized as active, the server will issue a "subscription-started" notification. After that, the server will send notifications to the receiver as per the subscription notification. Note that the server assumes that the receiver is ready to accept notifications on the NETCONF session. This may require coordination between the client that configures the subscription and the clients for which the notifications are intended. This coordination is out of the scope of this document.
The session is only intended for pushing notifications. Client requests on that session SHOULD be ignored by the server.
The contents sent by the server on the Call Home session, once established, are identical to those in a dynamic subscription.
Once the subscription configuration is active, if NETCONF transport is needed but does not exist to one or more target IP address plus port, the server initiates a transport session via [RFC8071] to those receiver(s) in the subscription using the address and port specified.
+----------+ +-----------+ +---------+ +---------+
| Client | | Server | | Rcver A | | Rcver B |
+----------+ +-----------+ +---------+ +---------+
| | | |
| Capability Exchange | | |
|<-------------------------->| | |
| | | |
| | | |
| Edit-config | | |
|--------------------------->| | |
| RPC Reply: OK | | |
|<---------------------------| | |
| | Call Home | |
| |<-------------->| |
| |<--------------------------->|
| | | |
| | Subscription | |
| | Started | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
| | Notification | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
Figure 18: Message flow for configured subscription establishment
Configured subscriptions can be modified using configuration operations against the top-level subtree subscription-config.
For example, the subscription established in the previous section could be modified as follows, choosing a different receiver:
<rpc message-id="102"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<running/>
</target>
<subscription-config
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<subscription>
<identifier>
1922
</identifier>
<stream>
foo
</stream>
<receiver>
<address>
1.2.3.5
</address>
<port>
1234
</port>
</receiver>
</subscription>
</subscription-config>
</edit-config>
</rpc>
Figure 19: Modify configured subscription
if the request is accepted, the server would reply:
<rpc-reply message-id="102"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ok/>
</rpc-reply>
Figure 20: A successful configured subscription modification
+----------+ +-----------+ +---------+ +---------+
| Client | | Server | | Rcver A | | Rcver B |
+----------+ +-----------+ +---------+ +---------+
| | | |
| Capability Exchange | | |
|<-------------------------->| | |
| | | |
| | | |
| Edit-config | | |
|--------------------------->| | |
| RPC Reply: OK | | |
|<---------------------------| | |
| | Call Home | |
| |<-------------->| |
| |<--------------------------->|
| | | |
| | Subscription | |
| | Started | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
| | Notification | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
| Edit-config | | |
|--------------------------->| | |
| RPC Reply: OK | | |
|<---------------------------| | |
| | Subscription | |
| | Modified | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
| | Notification | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
Figure 21: Message flow for subscription modification (configured subscription)
Subscriptions can be deleted using configuration operations against the top-level subtree subscription-config. For example:
<rpc message-id="103"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<running/>
</target>
<subscription-config
xmlns:xc="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<subscription xc:operation="delete">
<identifier>
1922
</identifier>
</subscription>
</subscription-config>
</edit-config>
</rpc>
<rpc-reply message-id="103"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<ok/>
</rpc-reply>
Figure 22: Deleting a configured subscription
+----------+ +-----------+ +---------+ +---------+
| Client | | Server | | Rcver A | | Rcver B |
+----------+ +-----------+ +---------+ +---------+
| | | |
| Capability Exchange | | |
|<-------------------------->| | |
| | | |
| | | |
| Edit-config | | |
|--------------------------->| | |
| RPC Reply: OK | | |
|<---------------------------| | |
| | Call Home | |
| |<-------------->| |
| |<--------------------------->|
| | | |
| | Subscription | |
| | Started | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
| | | |
| | Notification | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
| Edit-config | | |
|--------------------------->| | |
| RPC Reply: OK | | |
|<---------------------------| | |
| | Subscription | |
| | Terminated | |
| | (id 22) | |
| |--------------->| |
| |---------------------------->|
| | | |
Figure 23: Message flow for subscription deletion (configured subscription)
Once a dynamic or configured subscription has been created, the NETCONF server sends (asynchronously) event notifications from the subscribed stream to receiver(s) over NETCONF. We refer to these as data plane notifications. The data model for Event Notifications is defined in [subscribe].
The following is an example of an event notification from [RFC6020]:
notification link-failure {
description "A link failure has been detected";
leaf if-name {
type leafref {
path "/interface/name";
}
}
leaf if-admin-status {
type admin-status;
}
leaf if-oper-status {
type oper-status;
}
}
Figure 24: Definition of an event notification
This notification might result in the following, prior to it being placed into NETCONF. Note that the mandatory eventTime and Subscription id have been added.
<notification
xmlns=" urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<eventTime>2007-09-01T10:00:00Z</eventTime>
<link-failure xmlns="http://acme.example.com/system">
<if-name>so-1/2/3.0</if-name>
<if-admin-status>up</if-admin-status>
<if-oper-status>down</if-oper-status>
</link-failure>
</notification>
Figure 25: Event notification
In addition to data plane notifications, a publisher may send subscription state notifications (defined in [subscribe]) to indicate to receivers that an event related to the subscription management has occurred. Subscription state notifications cannot be filtered out. Next we exemplify them:
A subscription-started would look like:
<notification
xmlns=" urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<eventTime>2007-09-01T10:00:00Z</eventTime>
<subscription-started
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0"/>
<identifier>39</identifier>
<stream>NETCONF</stream>
</subscription-started/>
</notification>
Figure 26: subscription-started subscription state notification
The subscription-modified is identical, with just the word "started" being replaced by "modified".
A subscription-completed would look like:
<notification
xmlns=" urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<eventTime>2007-09-01T10:00:00Z</eventTime>
<subscription-completed
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<identifier>39</identifier>
</subscription-completed>
</notification>
Figure 27: subscription-completed notification in XML
The equivalent using JSON encoding would be:
<notification
xmlns=" urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<eventTime>2007-09-01T10:00:00Z</eventTime>
<notification-contents-json>
{
"sn:subscription-completed": {
"identifier" : 39
}
</notification-contents-json>
</notification>
Figure 28: subscription-completed notification in JSON
The subscription-resumed and replay-complete are virtually identical, with "subscription-completed" simply being replaced by "subscription-resumed" and "replay-complete" in both encodings.
A subscription-terminated would look like:
<notification
xmlns=" urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<eventTime>2007-09-01T10:00:00Z</eventTime>
<subscription-terminated
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
<identifier>39</identifier>
<error-id>error-insufficient-resources</error-id>
</subscription-terminated>
</notification>
Figure 29: subscription-modified subscription state notification
The above, and the subscription-suspended are virtually identical, with "subscription-terminated" simply being replaced by "subscription-suspended".
+------------+ +-----------+
| Client | | Server |
+------------+ +-----------+
| |
| Capability Exchange |
|<---------------------------->|
| |
| Establish Subscription |
|<---------------------------->|
| |
| Notification |
|<-----------------------------|
| |
| |
| Subscription Suspended |
|<-----------------------------|
| |
| |
| |
| Subscription Resumed |
|<-----------------------------|
| |
| Notification |
|<-----------------------------|
| |
Figure 30: subscription-suspended and resumed notifications
+----------+ +-----------+ +---------+ +---------+
| Client | | Server | | Rcver A | | Rcver B |
+----------+ +-----------+ +---------+ +---------+
| | | |
| Capability Exchange | | |
|<-------------------------->| | |
| | | |
| Edit-config | | |
|--------------------------->| | |
| RPC Reply: OK | | |
|<---------------------------| | |
| | Subscription | |
| | Started | |
| |--------------->| |
| |---------------------------->|
| | | |
| | Notification | |
| |--------------->| |
| |---------------------------->|
| | | |
| | Subscription | |
| | Suspended | |
| |--------------->| |
| | | |
| | Notification | |
| |---------------------------->|
| | | |
| | Subscription | |
| | Resumed | |
| |--------------->| |
| | | |
| | Notification | |
| |--------------->| |
| |---------------------------->|
| | | |
Figure 31: Suspended and resumed notifications for a single configured receiver
The :interleave capability is originally defined in [RFC5277]. It is incorporated in this document with essentially the same semantics. That is, the NETCONF server MUST receive, process, and respond to NETCONF requests on a session with active notification subscriptions.
The :interleave capability is identified by the following string: urn:ietf:params:netconf:capability:interleave:1.0
Note that subscription operations MUST be received, processed, and responded on a session with active notification subscriptions That mandatory requirement together with the :interleave capability permits a client performing all operations against a server using a single connection, allowing for better scalability with respect to the number of NETCONF sessions required to manage an entity.
The <notification> elements are never sent before the transport layer and the NETCONF layer, including capabilities exchange, have been established and the manager has been identified and authenticated.
A secure transport must be used and the server must ensure that the user has sufficient authorization to perform the function they are requesting against the specific subset of content involved.
The contents of notifications, as well as the names of event streams, may contain sensitive information and care should be taken to ensure that they are viewed only by authorized users. The NETCONF server MUST NOT include any content in a notification that the user is not authorized to view.
If a malicious or buggy NETCONF client sends a number of <establish-subscription>requests, then these subscriptions accumulate and may use up system resources. In such a situation, subscriptions MAY be terminated by terminating the suspect underlying NETCONF sessions. The server MAY also suspend or terminate a subset of the active subscriptions on the NETCONF session .
Configured subscriptions from one or more publishers could be used to overwhelm a receiver, which perhaps doesn't even support subscriptions. Clients that do not want pushed data need only terminate or refuse any transport sessions from the publisher.
The NETCONF Authorization Control Model [RFC6536] SHOULD be used to control and restrict authorization of subscription configuration. This control models permits specifying per-user permissions to receive specific event notification types. The permissions are specified as a set of access control rules.
We wish to acknowledge the helpful contributions, comments, and suggestions that were received from: Andy Bierman, Yan Gang, Sharon Chisholm, Hector Trevino, Peipei Guo, Susan Hares, Tim Jenkins, Balazs Lengyel, Kent Watsen, and Guangying Zheng.
| [RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
| [RFC5277] | Chisholm, S. and H. Trevino, "NETCONF Event Notifications", RFC 5277, DOI 10.17487/RFC5277, July 2008. |
| [RFC6020] | Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010. |
| [RFC6241] | Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011. |
| [RFC6536] | Bierman, A. and M. Bjorklund, "Network Configuration Protocol (NETCONF) Access Control Model", RFC 6536, DOI 10.17487/RFC6536, March 2012. |
| [RFC8071] | Watsen, K., "NETCONF Call Home and RESTCONF Call Home", RFC 8071, DOI 10.17487/RFC8071, February 2017. |
| [subscribe] | Voit, Eric., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard, E. and A. Tripathy, "Custom Subscription to Event Notifications", September 2017. |
| [yang-push] | Clemm, A., Gonzalez Prieto, A., Voit, Eric., Tripathy, A., Nilsen-Nygaard, E., Bierman, A. and B. Lengyel, "Subscribing to YANG datastore push updates", September 2017. |
(To be removed by RFC editor prior to publication)
(To be removed by RFC editor prior to publication)