Skip to main content

Extensions to Yang Push
draft-ranade-netmod-yang-push-extension-00

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft whose latest revision state is "Expired".
Author Rohit R Ranade
Last updated 2019-02-04
RFC stream (None)
Formats
Additional resources
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date (None)
Responsible AD (None)
Send notices to (None)
draft-ranade-netmod-yang-push-extension-00
NETMOD Working Group                                           R. Ranade
Internet-Draft                                                    Huawei
Intended status: Standards Track                            Feb 01, 2019
Expires: August 5, 2019

                        Extensions to Yang Push
               draft-ranade-netmod-yang-push-extension-00

Abstract

   This document defines extensions to the yang push subscription
   mechanism, which can provide more granularity in tracking
   configuration changes in datastores.

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 August 5, 2019.

Copyright Notice

   Copyright (c) 2019 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.

Ranade                   Expires August 5, 2019                 [Page 1]
Internet-Draft           Extensions to Yang Push                Feb 2019

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Yang Push Subscription Extensions . . . . . . . . . . . . . .   3
     2.1.  Config Filter . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Origin Metadata Attribute . . . . . . . . . . . . . . . .   3
   3.  Examples of usage . . . . . . . . . . . . . . . . . . . . . .   3
   4.  YANG Module . . . . . . . . . . . . . . . . . . . . . . . . .   5
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     7.2.  URIs  . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   9

1.  Introduction

   The subscription mechanism defined in yang-push draft
   [I-D.ietf-netconf-yang-push] supports a subscription mechanism where
   datastore and its datanodes can be provided as targets.  However
   there are a few scenarios where a subscription to datanodes may not
   be sufficient.

   o  An application on the client may want to track ONLY the
      configuration changes in a particular module.  If a module
      contains "config true" mixed with "config false" nodes, setting up
      such a filter at multiple levels will be cumbersome.

   o  An application on the client may want to track the configuration
      (other than intended) which the device applied.  Yang-push
      subscription does not provide such control.

1.1.  Terminology

   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.

   The following terms are defined in [RFC8342] and are not redefined
   here:

   o  operational state datastore

   o  intended configuration datastore

Ranade                   Expires August 5, 2019                 [Page 2]
Internet-Draft           Extensions to Yang Push                Feb 2019

2.  Yang Push Subscription Extensions

   There are two new filter nodes added to the Yang push subscription
   mechanism.  They are listed below.

   o  config-filter

   o  with-origin

2.1.  Config Filter

   This is a filter for nodes with the given value for their 'config'
   property.  When this leaf is set to 'true', only 'config true' nodes
   are selected and, when set to 'false', only 'config false' nodes are
   selected.  If this leaf is not present, this filter is not applied.

2.2.  Origin Metadata Attribute

   This document defines the "with-origin" parameter, which if present,
   requests that the server includes "origin" metadata annotations as
   defined in [RFC8342] in notifications which are part of this
   subscription.  This parameter is only valid for the operational state
   datastore and any datastores with identities derived from the
   "operational" identity.  Otherwise, if an invalid datastore is
   specified then a suitable error is returned.

   Data in the operational state datastore can come from multiple
   sources.  The server should return the most accurate value for the
   "origin" metadata annotation as possible, indicating the source of
   the operational value, as specified in Section 5.3.4 of RFC8342 [1]

   When encoding the origin metadata annotation for a hierarchy of
   returned nodes, the annotation may be omitted for a child node when
   the value matches that of the parent node, as described in the "ietf-
   origin" YANG module [RFC8342].

   The "with-origin" parameter is optional to support.  It is identified
   with the feature "origin".

3.  Examples of usage

   In this example, the following fictional module is used:

Ranade                   Expires August 5, 2019                 [Page 3]
Internet-Draft           Extensions to Yang Push                Feb 2019

   module example-interface {
     yang-version 1.1;
     namespace urn:example:interface;
     prefix int;

     import ietf-inet-types {
       prefix inet;
     }

     container interface {
       leaf name{
         type string;
       }

       leaf speed{
         type string;
         config false;
       }
     }
   }

   A subscription on the "config true" nodes of the operational state
   datastore.  This subscription also requests to get the origin of the
   datanodes as part of Yang-push notifications.  This is considering
   that the NETCONF protocol was used for this subscription.

   <rpc xmlns="urn:ietf:params:xml:ns:netconf:1.0">
     <establish-subscription \
           xmlns="urn:ietf:params:xml:ns:netconf:1.0" \
           xmlns:yp="urn:ietf:params:xml:ns:netconf:1.0" \
           xmlns:ypext="urn:ietf:params:xml:ns:netconf:1.0">
       <yp:datastore>operational</yp:datastore>
       <ypext:config-filter>true</ypext:config-filter>
       <ypext:with-origin/>
     </establish-subscription>
   </rpc>

   The operator has configured an interface ("eth1"), the system has
   recognised an interface ("eth0") which was plugged in recently.  The
   below NETCONF notification is an example for a yang-push notification
   when the device applies the "eth0" configuration.

Ranade                   Expires August 5, 2019                 [Page 4]
Internet-Draft           Extensions to Yang Push                Feb 2019

   <notification \
         xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
     <eventTime>2019-01-25T08:00:11.22Z</eventTime>
     <push-change-update
           xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push" \
           xmlns:or="urn:ietf:params:xml:ns:yang:ietf-origin" >
       <id>10</id>
       <datastore-changes>
         <yang-patch>
           <patch-id>1</patch-id>
           <edit>
             <edit-id>edit1</edit-id>
             <operation>create</operation>
             <target>/example-interface:interface</target>
             <value>
               <interface xmlns="urn:example:interface" \
                     or:origin="or:system">
                 <name>eth0</name>
               </interface>
             </value>
           </edit>
       </yang-patch>
     </push-change-update>
   </notification>

4.  YANG Module

    <CODE BEGINS> file "ietf-yang-push-ext@2019-02-01.yang"
    module ietf-yang-push-ext {
      yang-version 1.1;
      namespace "urn:ietf:params:xml:ns:yang:ietf-yang-push-ext";
      prefix ypext;

      import ietf-subscribed-notifications {
        prefix sn;
      }

      import ietf-yang-push {
        prefix yp;
      }

      import ietf-datastores {
        prefix ds;
        reference "RFC 8342: Network Management Datastore Architecture.";
      }

      import ietf-origin {
        prefix or;

Ranade                   Expires August 5, 2019                 [Page 5]
Internet-Draft           Extensions to Yang Push                Feb 2019

        reference "RFC 8342: Network Management Datastore Architecture.";
      }

      organization
        "IETF NETMOD (Network Modeling) Working Group";
      contact
        "WG Web:   <http://tools.ietf.org/wg/netmod/>
         WG List:  <mailto:netmod@ietf.org>
         WG Chair: Kent Watsen
                   <mailto:kwatsen@juniper.net>

         Editor:   Rohit Ranade
                   <mailto:rohitrranade@huawei.com>";

      description
        "This module defines extensions to subscription mechanism
        to yang-push on operational state datastore.

        Copyright (c) 2019 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
        (https://trustee.ietf.org/license-info).

        The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
        NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and
        'OPTIONAL' in the module text are to be interpreted as described
        in RFC 2119 (https://tools.ietf.org/html/rfc2119).

        This version of this YANG module is part of RFC XXXX
        (https://tools.ietf.org/html/rfcXXXX); see the RFC itself for
        full legal notices.";

      revision 2019-02-01 {
        description
          "Initial revision.";
        reference "RFCXXXX";
      }

      feature origin {
        description
          "Indicates that the server supports the 'origin' annotation.";
        reference
          "RFC 8342: Network Management Datastore Architecture";

Ranade                   Expires August 5, 2019                 [Page 6]
Internet-Draft           Extensions to Yang Push                Feb 2019

      }

      grouping subscription-filter-extension{
        description
          "This grouping describes the extensions to subscription
           conditions.";
        leaf config-filter {
          type boolean;
          description
            "Filter for nodes with the given value for their 'config'
             property.  When this leaf is set to 'true', only 'config
             true' nodes are selected and, when set to 'false', only
             'config false' nodes are selected.  If this leaf is not
             present, this filter is not applied.";
        }

        leaf with-origin {
          when 'derived-from-or-self(../yp:datastore, "ds:operational")';
          if-feature origin;
          type empty;
          description
            "If this parameter is present, the server will return
             the 'origin' annotation for the nodes that has one.";
        }
      }

      augment "/sn:establish-subscription/sn:input/sn:target/ +
                  yp:datastore" {
        description
          "This augmentation adds the filter extensions for the
           subscription to RPC input.";
        uses subscription-filter-extension;
      }
    }
    <CODE ENDS>

5.  IANA Considerations

   This document registers one URI in the IETF XML Registry [RFC3688].
   The following registration has been made:

      URI: urn:ietf:params:xml:ns:yang:ietf-yang-push-oper-ext

      Registrant Contact: The IESG.

      XML: N/A, the requested URI is an XML namespace.

Ranade                   Expires August 5, 2019                 [Page 7]
Internet-Draft           Extensions to Yang Push                Feb 2019

   This document registers one YANG module in the YANG Module Names
   Registry [RFC6020].  The following registration has been made:

      name: ietf-yang-push-oper-ext

      namespace: urn:ietf:params:xml:ns:yang:ietf-yang-push-oper-ext

      prefix: ypext

      RFC: xxxx

6.  Security Considerations

   TBD.

7.  References

7.1.  Normative References

   [I-D.ietf-netconf-yang-push]
              Clemm, A., Voit, E., Prieto, A., Tripathy, A., Nilsen-
              Nygaard, E., Bierman, A., and B. Lengyel, "Subscription to
              YANG Datastores", draft-ietf-netconf-yang-push-21 (work in
              progress), January 2019.

   [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>.

   [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>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

7.2.  URIs

   [1] https://tools.ietf.org/html/rfc8342#section-5.3.4

Ranade                   Expires August 5, 2019                 [Page 8]
Internet-Draft           Extensions to Yang Push                Feb 2019

Author's Address

   Rohit R Ranade
   Huawei
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka   560066
   India

   Email: rohitrranade@huawei.com

Ranade                   Expires August 5, 2019                 [Page 9]