NETCONF Working Group Q. Wu Internet-Draft Q. Ma Intended status: Standards Track Huawei Expires: July 24, 2021 P. Liu China Mobile January 20, 2021 Telemetry Data Export capability draft-tao-netconf-data-export-capabilities-03 Abstract This document proposes a YANG module for telemetry data export capabilities which augments system Capabilities model and provides additional telemetry data export attributes associated with system capabilities for transport dependent capability advertisement. 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/. 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Expires July 24, 2021 [Page 1] Internet-Draft Data Export Capability January 2021 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. Data Export capability . . . . . . . . . . . . . . . . . . . 3 2.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 4 3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 4.1. Updates to the IETF XML Registry . . . . . . . . . . . . 10 4.2. Updates to the YANG Module Names Registry . . . . . . . . 10 5. Security Considerations . . . . . . . . . . . . . . . . . . . 11 6. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 11 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 7.1. Normative References . . . . . . . . . . . . . . . . . . 12 7.2. Informative References . . . . . . . . . . . . . . . . . 13 Appendix A. Usage Example of interaction with Adaptive Subscription . . . . . . . . . . . . . . . . . . . . 14 Appendix B. Usage Example of interaction with UDP based Transport for Configured Subscription . . . . . . . 16 Appendix C. Changes between Revisions . . . . . . . . . . . . . 17 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 1. Introduction Notification capabilities 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 capabilities 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 the client and the server may still support various different transport specific parameters (e.g., transport protocol, encoding format, encryption). As described in section 3.1 of [RFC8641], a simple negotiation (i.e., inserting hints into error responses to a failed RPC request) between subscribers and publishers for subscription parameters increases the likelihood of success for subsequent RPC requests, but not guaranteed, which may cause unexpected failure or additional message exchange between client and server. This document defines a corresponding solution that is built on top of [I-D.netconf-notification-capabilities]. Supplementing that work are YANG data model augmentations for transport dependent capability advertisement. Wu, et al. Expires July 24, 2021 [Page 2] Internet-Draft Data Export Capability January 2021 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: o A set of capabilities related to the amount of notifications the server can send out o Specification of which data nodes support on-change notifications. o Capability values can be specified on server level, datastore level or on specific data nodes (and their contained sub-tree) of a specific datastore. Capability values on a smaller, more specific part of the server's data always override more generic values. o On-change capability is not specified on a server level as different datastores usually have different on-change capabilities. On a datastore level on-change capability for configuration and state data can be specified separately. These server capabilities are transport independent, session level capabilities. They can be provided either at the implementation time or reported at the run time. This document augments system Capabilities model and provides additional data export attributes associated with system capabilities: o Specification of transport protocol the client can use to establish a transport connection; o Specification of the encoding selection used (e.g., XML or JSON, Binary) for Data Modeled with YANG; o Specification of secure transport mechanisms that are needed by the client to communicate with the server; Wu, et al. Expires July 24, 2021 [Page 3] Internet-Draft Data Export Capability January 2021 o Specification of the type of data compression algorithm (e.g., lossless data compression) the client can use for file compression and decompression o Specification of the notification message encapsulation type, either one notification per message or multiple notifications per message. o Specification of the update trigger type such as adaptive interval trigger, timer event based trigger, count threshold trigger, redundant suppression. 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? identityref +--ro encoding-format? identityref +--ro security-protocol? identityref +--ro compression-mode? identityref augment /sysc:system-capabilities/inc:subscription-capabilities: +--ro data-export-capabilities +--ro message-bundling-support? boolean augment /sysc:system-capabilities/sysc:datastore-capabilities/sysc:per-node-capabilities: +--ro data-export-capabilities +--ro adaptive-interval-support boolean +--ro timer-event-support? boolean +--ro counter-threshold-support? boolean +--ro suppress-redundant? boolean 3. YANG Module file "ietf-data-export-capabilities.yang" module ietf-data-export-capabilities { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-data-export-capabilities"; prefix dec; import ietf-system-capabilities { prefix sysc; } import ietf-notification-capabilities { prefix inc; } Wu, et al. Expires July 24, 2021 [Page 4] Internet-Draft Data Export Capability January 2021 organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: Editor: Qin Wu 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.) Wu, et al. Expires July 24, 2021 [Page 10] Internet-Draft Data Export Capability January 2021 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: o /sysc:system-capabilities/dec:transport-protocol o /sysc:system-capabilities/dec:encoding-format o /sysc:system-capabilities/dec:security-protocol o /sysc:system-capabilities/dec:compression-mode o /sysc:system-capabilities/inc:subscription-capabilities/ dec:message-bundling-support 6. Contributors Wu, et al. Expires July 24, 2021 [Page 11] Internet-Draft Data Export Capability January 2021 Ran Tao Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: taoran20@huawei.com Liang Geng China Mobile 32 Xuanwumen West St, Xicheng District Beijing 10053 Email: gengliang@chinamobile.com Thomas Graf Swisscom Binzring 17 Zuerich 8045 Switzerland Email: thomas.graf@swisscom.com 7. References 7.1. 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., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "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., Ed., "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, . Wu, et al. Expires July 24, 2021 [Page 12] Internet-Draft Data Export Capability January 2021 [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, . 7.2. Informative References [I-D.ietf-netconf-https-notif] Jethanandani, M. and K. Watsen, "An HTTPS-based Transport for Configured Subscriptions", draft-ietf-netconf-https- notif-06 (work in progress), November 2020. [I-D.ietf-netconf-udp-notif] Zheng, G., Zhou, T., Graf, T., Francois, P., and P. Lucente, "UDP-based Transport for Configured Subscriptions", draft-ietf-netconf-udp-notif-01 (work in progress), November 2020. [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . Wu, et al. Expires July 24, 2021 [Page 13] Internet-Draft Data Export Capability January 2021 [RFC6020] Bjorklund, M., Ed., "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, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . Appendix A. Usage Example of interaction with Adaptive Subscription The following instance-data example describes the notification capabilities of a hypothetical "acme-router". The router implements the running, and operational datastores. Every change can be reported on-change from running, but only config=true nodes and some config=false data from operational. Interface statistics are reported only when both adaptive-interval-support and count- threshold-support are set to true. acme-router-notification-capabilities ietf-system-capabilities@2020-03-23 ietf-notification-capabilities@2020-03-23 ietf-data-export-capabilities@2020-03-23 Defines the notification capabilities of an acme-router. The router only has running, and operational datastores. Every change can be reported on-change from running, but only config=true nodes and some config=false data from operational. Statistics are not reported based on timer based trigger and counter threshold based trigger. ds:operational /if:interfaces/if:interface/if:statistics Wu, et al. Expires July 24, 2021 [Page 14] Internet-Draft Data Export Capability January 2021 5 state-changes /if:interfaces/if:interface/if:statistics/if:out-octets false false /if:interfaces/if:interface/if:statistics/if:in-errors true true The client configure adaptive subscription parameters on the server. The adaptive subscription configuration parameters require the server to scan all interface of specific type every 5 seconds if the value of interface in-errors is greater than 1000; If the interface in- errors value is less than 1000, switch to 60 seconds period value, and then scan all client every 60 seconds. Wu, et al. Expires July 24, 2021 [Page 15] Internet-Draft Data Export Capability January 2021 ds:running /if:ietf-interfaces /if:interfaces/if:interface/if:statistics in-errors in-errors > 1000 1000 5 in-errors < 1000 1000 60 Appendix B. Usage Example of interaction with UDP based Transport for Configured Subscription Wu, et al. Expires July 24, 2021 [Page 16] Internet-Draft Data Export Capability January 2021 acme-router-notification-capabilities ietf-system-capabilities@2020-03-23 ietf-notification-capabilities@2020-03-23 ietf-data-export-capabilities@2020-03-23 Defines the notification capabilities of an acme-router. The router only has running, and operational datastores. Every change can be reported on-change from running, but only config=true nodes and some config=false data from operational. Statistics are not reported based on timer based trigger and counter threshold based trigger. udp binary Appendix C. Changes between Revisions v02 - v03 o Change 'data-export-capabilities' into list type to support multiple transport protocol, encoding on the server. o Add Usage Example of interaction with UDP based Transport for Configured Subscription. o Add Thomas Graf as a contributor; o Update motivation in the introduction to clarify why this work is needed. o Support udp notif and http notif as two optional transport in the YANG data model. Wu, et al. Expires July 24, 2021 [Page 17] Internet-Draft Data Export Capability January 2021 Authors' Addresses Qin Wu Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: bill.wu@huawei.com Qiufang Ma Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China Email: maqiufang1@huawei.com Peng Liu China Mobile 32 Xuanwumen West St, Xicheng District Beijing 10053 Email: liupengyjy@chinamobile.com Wu, et al. Expires July 24, 2021 [Page 18]