[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01 02

NETCONF Working Group                                            Z. Wang
Internet-Draft                                                     Q. Wu
Intended status: Standards Track                                  Huawei
Expires: January 4, 2021                                          P. Liu
                                                                  H. Cai
                                                            China Mobile
                                                            July 3, 2020


              Bulk Subscription to YANG Event Notification
          draft-wang-netconf-bulk-subscribed-notifications-02

Abstract

   This document defines a YANG data model and associated mechanism that
   allows subscriber applications to bulk subscribe to publishers' event
   streams based on bundle group information such as bundle size and
   bundle latency.  This allows the publishers to report multiple
   notifications in a single bundling message.

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 January 4, 2021.

Copyright Notice

   Copyright (c) 2020 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



Wang, et al.             Expires January 4, 2021                [Page 1]


Internet-Draft              Bulk Subscription                  July 2020


   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Model Overview  . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Bulk Subscription YANG Module . . . . . . . . . . . . . . . .   5
   4.  Bulk Notification YANG Module . . . . . . . . . . . . . . . .   9
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
     5.1.  Updates to the IETF XML Registry  . . . . . . . . . . . .  10
     5.2.  Updates to the YANG Module Names Registry . . . . . . . .  10
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  11
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  12
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   Subscription to YANG Notifications for Datastore Updates [RFC8641]
   uses a "target" object in subscription protocol operation for
   identifying the targeted source of information against which the
   subscription is applied and supports multiple subscriptions on a
   single transport session.  Notification Message Headers and Bundles
   [I-D.ietf-netconf-notification-messages] allows multiple
   notifications bundled into one transportable message.  However the
   subscription protocol operation doesn't provide specific criteria to
   classify subscriptions and therefore lacks the capability to
   explicitly indicate which specific subscription associated with the
   notification should be bundled together, e.g., subscription A and B
   are bundled based on their relationship with a set of YANG data
   models while subscription C and D are bundled based on "transport"
   and "encoding" parameters,both bundled groups are transported in the
   same transport session.  A bundle size, bundle latency associated
   with a set of subscriptions or YANG data models enables the ability
   to perform encapsulation operation on a set of subscriptions with
   common characteristics via a single transaction.  The bundle size and
   bundle latency provides a more optimal mechanism for notification
   encapsulation which would otherwise require multiple atomic
   transactions on a per subscription (i.e., one message per
   notification) basis.  Following are some of the use-cases where such
   identifier can be used.





Wang, et al.             Expires January 4, 2021                [Page 2]


Internet-Draft              Bulk Subscription                  July 2020


   o  For a dynamic subscription, the subscriber may have already had
      priori knowledge about correlation relation between
      subscriptions(e.g., aggregated subscribed data from multiple
      sources).  With this priori knowledge,it might send a bundle
      subscription RPC request to indicate what specific notifications
      associated with the subscription must be bundled together.

   o  For a configured subscription, self-explanation data Node tag
      capability advertisment describing correlation between data nodes
      in different YANG data model from different publisher can be used
      to further establish correlation relation between subscriptions.
      The correlation relation between subscriptions can be configured
      back onto publisher, which help determine which notifications can
      be bundles and which notifications are not.

   o  With the above bundle subscription indication from subscriber to
      the publisher, multiple notifications corresponding to the request
      protocol operation for those notifications are bundled into one
      transportable message using Notification Message Headers and
      Bundles defined in [I-D.ietf-netconf-notification-messages].

   This document defines a YANG data model and associated mechanism that
   classify subscription based on various different filtering criteria
   and allow subscriber applications to bulk subscribe/unsubscribe to
   publisher's targeted object source based on bundle size and bundle
   latency.  This also allows the publishers to report multiple
   notification in a single bundling message defined in [I-D.ietf-
   netconf-notification-messages].

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.

   This document uses the following terms:

   Event:  An event is something that happens that may be of interest -
      a configuration change, a fault, a change in status, crossing a
      threshold, or an external input to the system, for example.
      Often, this results in an asynchronous message, sometimes referred
      to as a notification or event notification, being sent to
      interested parties to notify them that this event has occurred
      [RFC5277].

   Client:  Defined in [RFC8342].



Wang, et al.             Expires January 4, 2021                [Page 3]


Internet-Draft              Bulk Subscription                  July 2020


   Configuration:   Defined in [RFC8342].

   Configured subscription:  Defined in [RFC8639]

   Configuration datastore:    Defined in [RFC8342].

   Event record:   A set of information detailing an event [RFC8639].

   Event stream:   A continuous, chronologically ordered set of events
      aggregated under some context [RFC8639].

   Notification message:   Information intended for a receiver
      indicating that one or more events have occurred [RFC8639].

   Publisher:  An entity responsible for streaming notification messages
      per the terms of a subscription [RFC8639].

   Receiver:  A target to which a publisher pushes subscribed event
      records.  For dynamic subscriptions, the receiver and subscriber
      are the same entity [RFC8639].

   Subscriber:   A client able to request and negotiate a contract for
      the generation and push of event records from a publisher.  For
      dynamic subscriptions, the receiver and subscriber are the same
      entity [RFC8639].

   Subscription:  A contract with a publisher, stipulating the
      information that one or more receivers wish to have pushed from
      the publisher without the need for further solicitation [RFC8639].

2.  Model Overview

   The YANG data model for the Bulk Subscriptions to YANG Event
   Notification has been split into two modules:

   o  The ietf-bulk-subscription.yang module defines a list for
      classifying different subscriptions corresponding to target object
      into groups.  Each group is associated with a bundle size, bundle
      latency and a set of subscriptions.  A set of subscription is
      identified by a "group-id" string.  This string is used both as an
      index within the bulk subscription module.  It associate a
      specific bundle group with a group of subscriptions and a set of
      YANG data models, as shown in the subscription augmentation.  In
      addition,ietf-subscribed-notifications.yang module defined in
      [RFC8639] is augmented with "max-bundle-size","max-bundle-latency"
      and "compression-algorithm" to enhance QoS feature and provide
      additional subscription bundle classification criteria.




Wang, et al.             Expires January 4, 2021                [Page 4]


Internet-Draft              Bulk Subscription                  July 2020


   o  The ietf-bulk-notification.yang module augment the YANG structure
      of ietf-notification-messages.yang [draft-ietf-netconf-
      notification-messages], a "group-id" is added to the "message-
      header" of the ietf-notification-messages.yang to indicate the
      group to which a set of notifications belongs.  In addition,
      "compression-algorithm" parameter is augmented to "message-header"
      to inform the corresponding recievers of compression algorithm to
      be used by the publisher.

   The following tree diagrams [RFC8340] provide an overview of the data
   model for "ietf-bulk-subscription.yang" module and the "ietf-bulk-
   notification.yang" module.

  module: ietf-bulk-subscription
    +--rw bundle-groups
       +--rw bundle-group* [group-id]
          +--rw group-id    string
          +--rw subscription-id*     leafref
          +--rw yang-module*         yang:yang-identifier

    augment /sn:subscriptions/sn:subscription:
       +--rw max-bundle-size         uint32
       +--rw max-bundle-latency      uint32
       +--rw compression-algorithm  string

    +---x bundle-subscription
       +---input
          +---w group-id?        -> /bundle-groups/bundle-group/group-id
          +--rw max-bundle-size         uint32
          +---w max-bundle-latency      uint32
          +---w compression-algorithm   string
          +---w subscription-id*        subscription-id
          +---w masked-subscription-id* subscription-id

  module: ietf-bulk-notification
       augment-structure /nm:message/nm:message-header:
          +--rw group-id?    string
          +--rw compression-algorithm string

3.  Bulk Subscription YANG Module

<CODE BEGINS> file "ietf-bulk-subscription@2019-09-23.yang"
module ietf-bulk-subscription {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-bulk-subscription";
  prefix bs;

  import ietf-subscribed-notifications {



Wang, et al.             Expires January 4, 2021                [Page 5]


Internet-Draft              Bulk Subscription                  July 2020


    prefix sn;
  }
  import ietf-yang-types {
    prefix yang;
  }

  organization
    "IETF NETCONF (Network Configuration) Working Group";
  contact
    "";
  description
    "NETCONF Protocol Data Types and Protocol Operations.

     Copyright (c) 2011 IETF Trust and the persons identified as
     the document authors.  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 6241; see
     the RFC itself for full legal notices.";

  revision 2019-09-23 {
    description
      "Initial revision";
       reference "RFC XXXX: Bulk Subscription to YANG Event Notification";
  }
  identity encode-cbor {
    base sn:encoding;
    description
      "Encode data using cbor.";
  }
  identity encode-gpb {
    base sn:encoding;
    description
      "Encode data using gpb.";
  }
  container bundle-groups {
    list bundle-group {
      key "group-id";
      leaf group-id {
        type string;
        description
          "This group ID is used as an index within the bulk subscription module



Wang, et al.             Expires January 4, 2021                [Page 6]


Internet-Draft              Bulk Subscription                  July 2020


           , which indicates subscription classification criteria.";
      }
      leaf-list subscription-id {
        type leafref {
         path "/sn:subscriptions/sn:subscription/sn:id";
        }
        description
          "subscription-id";
      }
    leaf-list yang-module {
      type yang:yang-identifier;
      description
        "Name of the YANG module list supported by the publisher.";
    }
      description
        "List for group that classify different subscriptions into groups.";
    }
    leaf compression-algorithm {
      type string;
      description
        "The technology with which an originator compress bytestream
         contents.";
    }
    description
      "Container for subscription group.";
  }
  augment "/sn:subscriptions/sn:subscription" {
      leaf max-bundle-size {
      type uint32;
      default 400;
      description
      "The maximum number of data objects to be included by the publisher in a
       single message to recievers.";
     }
      leaf max-bundle-latency {
      type uint32;
      units centiseconds;
      default 400;
      description
      "The maximum latency before a specific YANG Notifications generated
       must egress a publisher.";
     }
    leaf compression-algorithm {
      type string;
      description
        "The technology with which an originator compress bytestream
         contents.";
    }



Wang, et al.             Expires January 4, 2021                [Page 7]


Internet-Draft              Bulk Subscription                  July 2020


    description
      "Augment the subscribed-notifications module with transport specific information.";
  }

  rpc bundle-subscription {
   description
    "Bundle subscription. This paremeter indicates what subscription must be bundled together.";
    input {
     leaf group-id {
      type string;
      description
      "This group ID is used as an index within the bulk subscription module";
      }
    leaf-list subscription-id {
      type uint32;
      description
       "Subscription-id paremeter indicates what subscription must be bundled together.";
      }
   leaf-list mask-subscription-id {
      type uint32;
      description
       "Mask subscription-id paremeter indicates what subscription must
        not be bundled together.";
      }
      leaf max-bundle-size {
      type uint32;
      default 400;
      description
      "The maximum number of data objects to be included by the publisher in a single
       message to recievers.";
     }
     leaf max-bundle-latency {
      type uint32;
      units centiseconds;
      default 400;
      description
      "The maximum latency before a specific YANG Notifications generated
       must egress a publisher.";
     }
    leaf compression-algorithm {
      type string;
      description
        "The technology with which an originator compress bytestream
         contents.";
    }
    }
  }
}



Wang, et al.             Expires January 4, 2021                [Page 8]


Internet-Draft              Bulk Subscription                  July 2020


<CODE ENDS>

4.  Bulk Notification YANG Module

<CODE BEGINS> file "ietf-bulk-notification@2019-09-23.yang"
module ietf-bulk-notification {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-bulk-notification";
  prefix bn;

  import ietf-yang-structure-ext {
    prefix sx;
  }
  import ietf-notification-messages {
    prefix nm;
  }

  organization
    "IETF NETCONF (Network Configuration) Working Group";
  contact
    "";
  description
    "NETCONF Protocol Data Types and Protocol Operations.

     Copyright (c) 2011 IETF Trust and the persons identified as
     the document authors.  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 6241; see
     the RFC itself for full legal notices.";

  revision 2019-09-23 {
    description
      "Initial revision";
    reference
      "RFC XXXX: Bulk Subscription to YANG Event Notification";
  }

  sx:augment-structure "/nm:message/nm:message-header" {
     leaf group-id {
      type string;
      description



Wang, et al.             Expires January 4, 2021                [Page 9]


Internet-Draft              Bulk Subscription                  July 2020


        "To identify the group to which a set of notifications belongs.";
    }
    leaf compression-algorithm {
      type string;
      description
        "The technology with which an originator compress bytestream
         contents.";
    }
    description
      "Group related informations are added to the 'message-header' of
       the ietf-notification-messages to identify the group to which a
       set of notifications belongs and compression algorithms used by
       the publisher.";
  }
}
<CODE ENDS>

5.  IANA Considerations

5.1.  Updates to the IETF XML Registry

   This document registers two URIs in the IETF XML registry [RFC3688].
   Following the format in [RFC3688], the following registrations are
   requested to be made:

   ---------------------------------------------------------------------
      URI: urn:ietf:params:xml:ns:yang:ietf-bulk-subscription
      Registrant Contact: The IESG.
      XML: N/A, the requested URI is an XML namespace.

      URI: urn:ietf:params:xml:ns:yang:ietf-bulk-notification
      Registrant Contact: The IESG.
      XML: N/A, the requested URI is an XML namespace.
   ---------------------------------------------------------------------

5.2.  Updates to the YANG Module Names Registry

   This document registers two YANG modules in the YANG Module Names
   registry [RFC7950]. . Following the format in [RFC6020], the
   following registration has been made:











Wang, et al.             Expires January 4, 2021               [Page 10]


Internet-Draft              Bulk Subscription                  July 2020


   ---------------------------------------------------------------------
      Name:         ietf-bulk-subscription
      Namespace:    urn:ietf:params:xml:ns:yang:ietf-bulk-subscription
      Prefix:       trig
      Reference:    RFC xxxx

      Name:         ietf-bulk-notification
      Namespace:    urn:ietf:params:xml:ns:yang:ietf-bulk-notification
      Prefix:       evt
      Reference:    RFC xxxx
   ---------------------------------------------------------------------

6.  Security Considerations

   The YANG module specified in this document defines a schema for data
   that is designed to be accessed via network management protocols such
   as NETCONF [RFC6241] or RESTCONF [RFC8040].  The lowest NETCONF layer
   is the secure transport layer, and the mandatory-to-implement secure
   transport is Secure Shell (SSH) [RFC6242].  The lowest RESTCONF layer
   is HTTPS, and the mandatory-to-implement secure transport is TLS
   [RFC8446].

   The NETCONF Configuration Access Control Model (NACM) [RFC8341]
   provides the means to restrict access for particular NETCONF or
   RESTCONF users to a preconfigured subset of all available NETCONF or
   RESTCONF protocol operations and content.

   There are a number of data nodes defined in this YANG module that are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive in some
   network environments.  Write operations (e.g., edit-config) to these
   data nodes without proper protection can have a negative effect on
   network operations.  These are the subtrees and data nodes and their
   sensitivity/vulnerability:

   o  /bundle-groups/bundle-group/group-id

   o  /sn:subscriptions/sn:subscription/bs:max-bundle-latency

   o  /sn:subscriptions/sn:subscription/bs:max-bundle-size

   o  /bundle-subscription/input/group-id

7.  Acknowledgements

   Thanks to Eric Voit for reviewing this draft and providing important
   input to this document.




Wang, et al.             Expires January 4, 2021               [Page 11]


Internet-Draft              Bulk Subscription                  July 2020


8.  References

8.1.  Normative References

   [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>.

   [RFC5277]  Chisholm, S. and H. Trevino, "NETCONF Event
              Notifications", RFC 5277, DOI 10.17487/RFC5277, July 2008,
              <https://www.rfc-editor.org/info/rfc5277>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [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>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [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>.



Wang, et al.             Expires January 4, 2021               [Page 12]


Internet-Draft              Bulk Subscription                  July 2020


   [RFC8407]  Bierman, A., "Guidelines for Authors and Reviewers of
              Documents Containing YANG Data Models", BCP 216, RFC 8407,
              DOI 10.17487/RFC8407, October 2018,
              <https://www.rfc-editor.org/info/rfc8407>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

   [RFC8639]  Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
              E., and A. Tripathy, "Subscription to YANG Notifications",
              RFC 8639, DOI 10.17487/RFC8639, September 2019,
              <https://www.rfc-editor.org/info/rfc8639>.

   [RFC8641]  Clemm, A. and E. Voit, "Subscription to YANG Notifications
              for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
              September 2019, <https://www.rfc-editor.org/info/rfc8641>.

8.2.  Informative References

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

Authors' Addresses

   Michael Wang
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: wangzitao@huawei.com









Wang, et al.             Expires January 4, 2021               [Page 13]


Internet-Draft              Bulk Subscription                  July 2020


   Qin Wu
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: bill.wu@huawei.com


   Peng Liu
   China Mobile
   32 Xuanwumen West St, Xicheng District
   Beijing  10053

   Email: liupengyjy@chinamobile.com


   Hui Cai
   China Mobile
   32 Xuanwumen West St, Xicheng District
   Beijing  10053

   Email: caihui@chinamobile.com




























Wang, et al.             Expires January 4, 2021               [Page 14]


Html markup produced by rfcmarkup 1.129d, available from https://tools.ietf.org/tools/rfcmarkup/