NETCONF Working Group R. Tao
Internet-Draft Q. Wu
Intended status: Standards Track Huawei
Expires: September 4, 2020 L. Geng
China Mobile
March 3, 2020

Telemetry Data Export capability
draft-tao-netconf-data-export-capabilities-00

Abstract

This document proposes a YANG module for telemetry data export capability which augments system Capabilities model and provide additional telemetry data export attributes associated with system capability for transport dependent capability negotiation.

Status of This Memo

This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.

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This Internet-Draft will expire on September 4, 2020.

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 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

Notification capability model defined in [I-D.netconf-notification- capabilities] allows a client to discover a set of capabilities supported by the server (e.g., basic system capability and YANG-Push related capabilities) both at implementation-time and run- time. These "capabilities" permit the client to adjust its behavior to take advantage of the features exposed by the device.

However pre-configuration for some transport specific parameters (e.g., transport protocol, encoding format, encryption by the client is still inevitable, which may cause unexpected failure and additional message exchange between client and server.

This document proposes a YANG module for telemetry data export capability which augments System Capabilities model and provide additional data export attributes for transport dependent capability negotiation.

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.

2. Data Export capability

The YANG module ietf-notification-capabilities defined in [I- D.netconf-notification-capabilities] specify the following server capabilities related to YANG Push:

These server capabilities are transport independent and session level capabilities and can be provided either at implementation time or reported at run time.

This document augments system Capabilities model and provides additional data export attributes associated with system capabilities:

2.1. Tree Diagram

The following tree diagram [RFC8340] provides an overview of the data model.

    module: ietf-data-export-capabilities
    augment /sysc:system-capabilities:
        +--ro data-export-capabilities 
           +--ro transport-protocol             transport-protocol
           +--ro encoding-format                encoding-format
           +--ro secure-transport               secure-transport
           +--ro compression-mode               compression-mode
           +--ro max-nodes-per-sensor-group     unint32
           +--ro max-sensor-group-per-update    unint32
    augment /sysc:system-capabilities/inc:subscription-capabilities:
        +--ro message-bundling-support          boolean
        +--ro subscription-mode                 subscription-mode
    augment /sysc:system-capabilities/sysc:datastore-capabilities/ +
                sysc:per-node-capabilities:
        +--ro sampling-interval*                centiseconds
        +--ro threshold-support                 boolean

3. YANG Module

<CODE BEGINS> file "ietf-data-export-capabilities.yang"
module ietf-data-export-capabilities {
  yang-version 1.1;
  namespace urn:ietf:params:xml:ns:yang:ietf-notification-data-export-capabilities;
  prefix dec;
  import ietf-system-capabilities  { prefix sysc ; }
  import ietf-notification-capabilities { prefix inc; }
  organization
    "IETF NETCONF (Network Configuration) Working Group";
  contact
    "WG Web:   <https://tools.ietf.org/wg/netconf/>
     WG List:  <mailto:netconf@ietf.org>
     Editor:   Ran Tao
               <mailto:taoran20@huawei.com>
               Qin Wu
               <mailto:bill.wu@huawei.com";
  description
    "This module defines an extension to System Capability and YANG Push
     Notification Capabilities model and provides additional data export
    attributes for transport dependent capability negotiation.

     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
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX;
     see the RFC itself for full legal notices.";
     /* Identities */
      identity transport-protocol {
       description
        "Base identity for transport protocol type.";
      }

     identity tcp {
      base transport-protocol;
       description
        "Identity for tcp transport protocol.";
     }

     identity udp {
       base transport-protocol;
       description
        "Identity for udp transport protocol.";
     }

     identity grpc {
       base transport-protocol;
       description
        "Identity for grpc transport protocol.";
     }

      identity security-protocol {
       description
        "Base identity for security protocol type.";
      }

     identity tls {
      base security-protocol;
       description
        "Identity for tls security protocol.";
     }

     identity ssh {
       base security-protocol;
       description
        "Identity for ssh transport protocol.";
     }

      identity encoding-format {
       description
        "Base identity for encoding format type.";
      }

     identity xml {
      base encoding-format;
       description
        "Identity for xml encoding format.";
     }

     identity json {
       base encoding-format;
       description
        "Identity for json encoding format.";
     }

     identity gpb {
       base encoding-format;
       description
        "Identity for gpb encoding format.";
     }
     identity cbor {
       base encoding-format;
       description
        "Identity for cbor encoding format.";
     }
      identity compression-mode {
       description
        "Base identity for compression mode.";
      }

     identity gzip {
      base security-protocol;
       description
        "Identity for gzip compression mode.";
     }

     identity deflate {
       base security-protocol;
       description
        "Identity for deflate compression mode.";
     }

      identity subscription-mode {
       description
        "Base identity for subscription mode.";
      }

     identity periodic {
      base subscription-mode;
       description
        "Identity for periodic subscription mode.";
     }

     identity on-change {
       base subscription-mode;
       description
        "Identity for on change subscription mode.";
     }
    identity event {
       base subscription-mode;
       description
        "Identity for event based subscription mode.";
     }
    augment /sysc:system-capabilities {
     description "Add system level capability.";
        container data-export-capabilities {
      description "Capabilities related to transport dependent capability negotiation.";
        leaf transport-protocol {
              type identityref {
               base transport-protocol;
            }
           description
            "Type of transport protocol.";
         }
         leaf encoding-format {
           type identityref {
              base encoding-format;
           }
           description
             "Type of encoding format.";
         }
         leaf security-protocol {
          type identityref {
             base security-protocol;
          }
          description
           "Type of secure transport.";
         }
       leaf compression-mode{
         type identityref {
            base compression-mode;
         }
         description
          "Type of compression mode.";
      }
      leaf max-nodes-per-sensor-group {
        type uint32 {
              range "1..max";
        }
        description
          "Maximum number of selected data nodes that can be sent
           per sensor group.";
      }
      leaf max-sensor-group-per-update {
        type uint32 {
              range "1..max";
        }
        description
          "Maximum number of sensor groups that can be sent
           in an update.";
      }
    }
  }
    augment /sysc:system-capabilities/inc:subscription-capabilities {
     description "Add subscription level capability.";
         leaf message-bundling-support {
           type boolean;
            default false;
            description
             "Enables message bundling support.";
          }
         leaf subscription-mode {
              type identityref {
               base subscription-mode;
            }
           description
            "Type of subscription mode.";
         }
  }
    augment /sysc:system-capabilities/sysc:datastore-capabilities/sysc:per-node-capabilities {
     description "Add datastore and node level capability.";
        leaf-list sampling-interval {
          type uint32;
          units "centiseconds";
          description "Time-based start and stop triggers
          are used to define the Sampling intervals.  All packets 
          are selected that arrive at the Observation Point within 
          the time intervals defined by the start and stop triggers 
          (i.e., arrival time of the packet is larger than the start 
          time and smaller than the stop time).";
           reference
         "RFC 5475: Sampling and Filtering Techniques for IP Packet 
         Selection";
        }
      leaf threshold-support {
         type boolean;
         default false;
         description
         "Set to true if the subscription mode is event based
         subscription mode.  Set to false
         if event based subscription mode is not supported.";
      }
  }
}
<CODE ENDS>

4. IANA Considerations

4.1. Updates to the IETF XML Registry

This document registers a URI in the "IETF XML Registry" [RFC3688]. Following the format in [RFC3688], the following registration has been made:

   URI:
      urn:ietf:params:xml:ns:yang:ietf-data-export-capabilities
   Registrant Contact:
      The IESG.
   XML:
      N/A; the requested URI is an XML namespace.

4.2. Updates to the YANG Module Names Registry

This document registers one YANG module in the "YANG Module Names" registry [RFC6020]. Following the format in [RFC6020], the following registration has been made:

   name:
      ietf-data-export-capabilities
   namespace:
      urn:ietf:params:xml:ns:yang:ietf-data-export-capabilities
   prefix:
      dec
   reference:
      RFC XXXX (RFC Ed.: replace XXX with actual RFC number and remove
      this note.)

5. 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:

6. References

6.1. 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.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J. and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011.
[RFC7950] Bjorklund, M., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016.
[RFC8040] Bierman, A., Bjorklund, M. and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017.
[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.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018.
[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.
[RFC8407] Bierman, A., "Guidelines for Authors and Reviewers of Documents Containing YANG Data Models", BCP 216, RFC 8407, DOI 10.17487/RFC8407, October 2018.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018.

6.2. Informative References

[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010.
[RFC8340] Bjorklund, M. and L. Berger, "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018.

Authors' Addresses

Ran Tao Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China EMail: taoran20@huawei.com
Qin Wu Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China EMail: bill.wu@huawei.com
Liang Geng China Mobile 32 Xuanwumen West St, Xicheng District Beijing, 10053 EMail: gengliang@chinamobile.com