Network Working Group T. Graf Internet-Draft Swisscom Intended status: Standards Track B. Claise Expires: 7 January 2024 Huawei A. Huang Feng INSA-Lyon 6 July 2023 Support of Network Observation Timestamping in YANG Notifications draft-netconf-tgraf-yang-push-observation-time-00 Abstract This document extends the YANG Notification header with the YANG objects observation timestamping, both for the "push-update" and "push-change-update" notifications. 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 7 January 2024. Copyright Notice Copyright (c) 2023 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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Graf, et al. Expires 7 January 2024 [Page 1] Internet-Draft YANG Notifications Observation Time July 2023 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminologies . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Extend the Streaming Update Notifications . . . . . . . . . . 3 4. The "ietf-yang-push-netobs-timestamping" YANG Module . . . . 4 4.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 4 4.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 6.1. URI . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 6.2. YANG module name . . . . . . . . . . . . . . . . . . . . 11 7. Operational Considerations . . . . . . . . . . . . . . . . . 11 7.1. On Change Sync On Start . . . . . . . . . . . . . . . . . 11 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 9.1. Normative References . . . . . . . . . . . . . . . . . . 12 9.2. Informative References . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 1. Introduction To correlate network data among different Network Telemetry planes as described in Section 3.1 of [RFC9232] or among different YANG push subscription types defined in Section 3.1 of [RFC8641], network observation timestamping describes when the state change was observed or from when to when the data was accounted. This is essential for understanding the timely relationship among these different planes and YANG push subscription types. With [I-D.tgraf-netconf-notif-sequencing] the delay between the YANG Notification export and the arrival at the downstream system storing the data can be measured. With network observation timestamping described in this document, the delay between the network observation and the data export of the YANG push publisher process can be measured as well, extending the delay measurement scope from the time the network observation and storing the data. By extending the YANG Notification header with the YANG objects observation-time for periodical and state-changed-observation-time for on-change subscriptions these use cases can be addressed accordingly. 2. Terminologies The following terms are defined in [RFC8639] and are not redefined here: Graf, et al. Expires 7 January 2024 [Page 2] Internet-Draft YANG Notifications Observation Time July 2023 Publisher Receiver Subscription In addition, this document defines the following terms: Observation-time: Describes the measurement observation time for the "push-update" notification in a "periodical" subscription. State-changed-observation-time: Describes the time when the network state change was observed. 3. Extend the Streaming Update Notifications Besides the Subscription ID as described in Section 3.7 of [RFC8641], the following network observation time metadata objects are part of "push-update" and "push-change-update" notifications. observation-time: Describes the measurement observation time for the "push-update" notification in a "periodical" subscription. By comparing the "observation-time" of two "push-update" notifications, the collector can deduce the actual cadence of the measurements, and compare it with the configured one. state-changed-observation-time: Describes in the "push-change- update" notification in a "on-change" subscription the time when the network state change was observed after the subscription was initially established. In case of an "on-change sync on start" subscription it describes the time when the network state change was observed before the subscription was established. Figure 1 provides an example of a JSON encoded, [RFC8259], "push- change-update" notification message over HTTPS-based [I-D.ietf-netconf-https-notif] or UDP-based [I-D.ietf-netconf-udp-notif] transport for the same subscription. Graf, et al. Expires 7 January 2024 [Page 3] Internet-Draft YANG Notifications Observation Time July 2023 { "ietf-notification:notification": { "eventTime": "2023-02-04T16:30:11.22Z", "sysName": "example-router", "sequenceNumber": 187653, "ietf-yang-push:push-update": { "id": 1011, "observation-time": "2023-02-04T16:30:09.44Z", "datastore-xpath-filter": "ietf-interfaces:interfaces", "datastore-contents": { "ietf-interfaces:interface": { "name": { "eth0": { "oper-status": "up" } } } } } } } Figure 1: JSON Push Example for a subscription-modified notification message 4. The "ietf-yang-push-netobs-timestamping" YANG Module This YANG module augments the "ietf-yang-push" module with the observation-time in the "push-update" and "push-change-update" streaming update notifications. 4.1. Data Model Overview 4.1.1. Tree View The following is the YANG tree diagram [RFC8340] for the ietf-yang- push-netobs-timestamping YANG module module: ietf-yang-push-netobs-timestamping augment /yp:push-update: +--ro observation-time? yang:date-and-time augment /yp:push-change-update: +--ro state-changed-observation-time? yang:date-and-time Graf, et al. Expires 7 January 2024 [Page 4] Internet-Draft YANG Notifications Observation Time July 2023 4.1.2. Full Tree View The following is the YANG tree diagram [RFC8340] for the ietf-yang- push-netobs-timestamping augmentation within the ietf-subscribed- notifications, including the RPCs and notifications. module: ietf-yang-push augment /sn:establish-subscription/sn:input: +---w (update-trigger)? +--:(periodic) | +---w periodic! | +---w period centiseconds | +---w anchor-time? yang:date-and-time +--:(on-change) {on-change}? +---w on-change! +---w dampening-period? centiseconds +---w sync-on-start? boolean +---w excluded-change* change-type augment /sn:establish-subscription/sn:input/sn:target: +--:(datastore) +-- datastore identityref +-- (selection-filter)? +--:(by-reference) | +-- selection-filter-ref | selection-filter-ref +--:(within-subscription) +-- (filter-spec)? +--:(datastore-subtree-filter) | +-- datastore-subtree-filter? | {sn:subtree}? +--:(datastore-xpath-filter) +-- datastore-xpath-filter? yang:xpath1.0 {sn:xpath}? augment /sn:modify-subscription/sn:input: +---w (update-trigger)? +--:(periodic) | +---w periodic! | +---w period centiseconds | +---w anchor-time? yang:date-and-time +--:(on-change) {on-change}? +---w on-change! +---w dampening-period? centiseconds augment /sn:modify-subscription/sn:input/sn:target: +--:(datastore) +-- datastore identityref +-- (selection-filter)? +--:(by-reference) Graf, et al. Expires 7 January 2024 [Page 5] Internet-Draft YANG Notifications Observation Time July 2023 | +-- selection-filter-ref | selection-filter-ref +--:(within-subscription) +-- (filter-spec)? +--:(datastore-subtree-filter) | +-- datastore-subtree-filter? | {sn:subtree}? +--:(datastore-xpath-filter) +-- datastore-xpath-filter? yang:xpath1.0 {sn:xpath}? augment /sn:subscription-started: +--ro (update-trigger)? +--:(periodic) | +--ro periodic! | +--ro period centiseconds | +--ro anchor-time? yang:date-and-time +--:(on-change) {on-change}? +--ro on-change! +--ro dampening-period? centiseconds +--ro sync-on-start? boolean +--ro excluded-change* change-type augment /sn:subscription-started/sn:target: +--:(datastore) +-- datastore identityref +-- (selection-filter)? +--:(by-reference) | +-- selection-filter-ref | selection-filter-ref +--:(within-subscription) +-- (filter-spec)? +--:(datastore-subtree-filter) | +-- datastore-subtree-filter? | {sn:subtree}? +--:(datastore-xpath-filter) +-- datastore-xpath-filter? yang:xpath1.0 {sn:xpath}? augment /sn:subscription-modified: +--ro (update-trigger)? +--:(periodic) | +--ro periodic! | +--ro period centiseconds | +--ro anchor-time? yang:date-and-time +--:(on-change) {on-change}? +--ro on-change! +--ro dampening-period? centiseconds +--ro sync-on-start? boolean +--ro excluded-change* change-type augment /sn:subscription-modified/sn:target: Graf, et al. Expires 7 January 2024 [Page 6] Internet-Draft YANG Notifications Observation Time July 2023 +--:(datastore) +-- datastore identityref +-- (selection-filter)? +--:(by-reference) | +-- selection-filter-ref | selection-filter-ref +--:(within-subscription) +-- (filter-spec)? +--:(datastore-subtree-filter) | +-- datastore-subtree-filter? | {sn:subtree}? +--:(datastore-xpath-filter) +-- datastore-xpath-filter? yang:xpath1.0 {sn:xpath}? augment /sn:filters: +--rw selection-filter* [filter-id] +--rw filter-id string +--rw (filter-spec)? +--:(datastore-subtree-filter) | +--rw datastore-subtree-filter? | {sn:subtree}? +--:(datastore-xpath-filter) +--rw datastore-xpath-filter? yang:xpath1.0 {sn:xpath}? augment /sn:subscriptions/sn:subscription: +--rw (update-trigger)? +--:(periodic) | +--rw periodic! | +--rw period centiseconds | +--rw anchor-time? yang:date-and-time +--:(on-change) {on-change}? +--rw on-change! +--rw dampening-period? centiseconds +--rw sync-on-start? boolean +--rw excluded-change* change-type augment /sn:subscriptions/sn:subscription/sn:target: +--:(datastore) +--rw datastore identityref +--rw (selection-filter)? +--:(by-reference) | +--rw selection-filter-ref | selection-filter-ref +--:(within-subscription) +--rw (filter-spec)? +--:(datastore-subtree-filter) | +--rw datastore-subtree-filter? | {sn:subtree}? +--:(datastore-xpath-filter) Graf, et al. Expires 7 January 2024 [Page 7] Internet-Draft YANG Notifications Observation Time July 2023 +--rw datastore-xpath-filter? yang:xpath1.0 {sn:xpath}? rpcs: +---x resync-subscription {on-change}? +---w input +---w id sn:subscription-id notifications: +---n push-update | +--ro id? sn:subscription-id | +--ro datastore-contents? | +--ro incomplete-update? empty | +--ro ypnt:observation-time? yang:date-and-time +---n push-change-update {on-change}? +--ro id? | sn:subscription-id +--ro datastore-changes | +--ro yang-patch | +--ro patch-id string | +--ro comment? string | +--ro edit* [edit-id] | +--ro edit-id string | +--ro operation enumeration | +--ro target target-resource-offset | +--ro point? target-resource-offset | +--ro where? enumeration | +--ro value? +--ro incomplete-update? empty +--ro ypnt:state-changed-observation-time? yang:date-and-time 4.2. YANG Module The YANG module has one leave augmenting the model of Subscription to YANG Notifications [RFC8639]. file "ietf-yang-push-netobs-timestamping@2023-03-06.yang" module ietf-yang-push-netobs-timestamping { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-yang-push-netobs-timestamping"; prefix ypnt; import ietf-yang-types { prefix yang; reference "RFC 6991: Common YANG Data Types"; Graf, et al. Expires 7 January 2024 [Page 8] Internet-Draft YANG Notifications Observation Time July 2023 } import ietf-yang-push { prefix yp; reference "RFC 8641: Subscription to YANG Notifications for Datastore Updates"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: Authors: Thomas Graf Benoit Claise Alex Huang Feng "; description "Defines YANG push event notification header with the observation time in push-update and push-change-update notifications. Copyright (c) 2023 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 Revised 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). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; revision 2023-03-06 { description "First revision"; reference "RFC XXXX: Support of YANG Notifications Observation Time"; } feature yang-push-change-update-obs-timestamp { description "This feature indicates the YANG-push Notifications support the observation timestamps in the push-change-update notifications."; } feature yang-push-update-obs-timestamp { Graf, et al. Expires 7 January 2024 [Page 9] Internet-Draft YANG Notifications Observation Time July 2023 description "This feature indicates the YANG-push Notifications support the observation timestamps in the push-update notifications."; } grouping yang-push-update-obs-timestamp { description "This grouping adds the start timestamp and the end timestamp of the observed metrics."; leaf observation-time { type yang:date-and-time; description "This is the time when metrics started counting."; } } grouping yang-push-change-update-obs-timestamp { description "This grouping adds the timestamp of the recorded event."; leaf state-changed-observation-time { type yang:date-and-time; description "This is the time when event happened."; } } // Event notifications augment "/yp:push-update" { description "This augmentation adds the start timestamp of the counted metrics in the push-update notification."; uses ypnt:yang-push-update-obs-timestamp; } augment "/yp:push-change-update" { description "This augmentation adds the timestamp of the event in the push-change-update notification."; uses ypnt:yang-push-change-update-obs-timestamp; } } 5. Security Considerations The security considerations for the YANG notifications subscription mechanism are described in [RFC8641]. This document adds no additional security considerations. Graf, et al. Expires 7 January 2024 [Page 10] Internet-Draft YANG Notifications Observation Time July 2023 6. IANA Considerations This document describes the URI used for the IETF XML Registry and registers a new YANG module name. 6.1. URI IANA is requested to add this document as a reference in the following URI in the IETF XML Registry [RFC3688]. URI: urn:ietf:params:xml:ns:yang:ietf-yang-push-netobs-timestamping Registrant Contact: The IESG. XML: N/A; the requested URI is an XML namespace. Reference: RFC5277; RFC-to-be 6.2. YANG module name This document registers the following YANG module in the YANG Module Names Registry [RFC6020], within the "YANG Parameters" registry: name: ietf-yang-push-netobs-timestamping namespace: urn:ietf:params:xml:ns:yang:ietf-yang-push-netobs- timestamping prefix: ypnt Reference: RFC-to-be 7. Operational Considerations 7.1. On Change Sync On Start For "on-change sync on start" subscriptions, if the timestamp for the network state change was observed before the subscription was established and is not recorded in the YANG datastore, then no timestamp should be populated to state-changed-observation-time. 8. Acknowledgements The authors would like to thank Rob Wilton, Nick Corran, Pierre Francois Ahmed Elhassany and Jean Quilbeuf for their review and valuable comments. 9. References Graf, et al. Expires 7 January 2024 [Page 11] Internet-Draft YANG Notifications Observation Time July 2023 9.1. Normative References [I-D.tgraf-netconf-notif-sequencing] Graf, T., Quilbeuf, J., and A. Huang Feng, "Support of Hostname and Sequencing in YANG Notifications", Work in Progress, Internet-Draft, draft-tgraf-netconf-notif- sequencing-00, February 2023, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [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, . [RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641, September 2019, . 9.2. Informative References [I-D.ietf-netconf-https-notif] Jethanandani, M. and K. Watsen, "An HTTPS-based Transport for YANG Notifications", Work in Progress, Internet-Draft, draft-ietf-netconf-https-notif-13, 4 November 2022, . [I-D.ietf-netconf-udp-notif] Zheng, G., Zhou, T., Graf, T., Francois, P., Feng, A. H., and P. Lucente, "UDP-based Transport for Configured Subscriptions", Work in Progress, Internet-Draft, draft- ietf-netconf-udp-notif-09, 10 March 2023, . Graf, et al. Expires 7 January 2024 [Page 12] Internet-Draft YANG Notifications Observation Time July 2023 [RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data Interchange Format", STD 90, RFC 8259, DOI 10.17487/RFC8259, December 2017, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC9232] Song, H., Qin, F., Martinez-Julia, P., Ciavaglia, L., and A. Wang, "Network Telemetry Framework", RFC 9232, DOI 10.17487/RFC9232, May 2022, . Authors' Addresses Thomas Graf Swisscom Binzring 17 CH-8045 Zurich Switzerland Email: thomas.graf@swisscom.com Benoit Claise Huawei Email: benoit.claise@huawei.com Alex Huang Feng INSA-Lyon Lyon France Email: alex.huang-feng@insa-lyon.fr Graf, et al. Expires 7 January 2024 [Page 13]