--- 1/draft-ietf-opsawg-model-automation-framework-01.txt 2020-03-17 01:13:15.403473254 -0700 +++ 2/draft-ietf-opsawg-model-automation-framework-02.txt 2020-03-17 01:13:15.475475086 -0700 @@ -1,25 +1,25 @@ -Networking Working Group Q. Wu, Ed. +OPSAWG Q. Wu, Ed. Internet-Draft Huawei Intended status: Informational M. Boucadair, Ed. -Expires: August 29, 2020 Orange +Expires: September 18, 2020 Orange D. Lopez Telefonica I+D C. Xie China Telecom L. Geng China Mobile - February 26, 2020 + March 17, 2020 A Framework for Automating Service and Network Management with YANG - draft-ietf-opsawg-model-automation-framework-01 + draft-ietf-opsawg-model-automation-framework-02 Abstract Data models for service and network management provides a programmatic approach for representing (virtual) services or networks and deriving (1) configuration information that will be communicated to network and service components that are used to build and deliver the service and (2) state information that will be monitored and tracked. Indeed, data models can be used during various phases of the service and network management life cycle, such as service @@ -47,21 +47,21 @@ 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 29, 2020. + This Internet-Draft will expire on September 18, 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 @@ -88,38 +88,38 @@ 4.1.4. Service Diagnosis . . . . . . . . . . . . . . . . . . 13 4.1.5. Service Decommission . . . . . . . . . . . . . . . . 13 4.2. Service Fullfillment Management Procedure . . . . . . . . 13 4.2.1. Intended Configuration Provision . . . . . . . . . . 13 4.2.2. Configuration Validation . . . . . . . . . . . . . . 14 4.2.3. Performance Monitoring/Model-driven Telemetry . . . . 14 4.2.4. Fault Diagnostic . . . . . . . . . . . . . . . . . . 15 4.3. Multi-layer/Multi-domain Service Mapping . . . . . . . . 15 4.4. Service Decomposing . . . . . . . . . . . . . . . . . . . 15 - 5. YANG Data Model Integration Examples . . . . . . . . . . . . 15 - 5.1. L3VPN Service Delivery . . . . . . . . . . . . . . . . . 15 + 5. YANG Data Model Integration Examples . . . . . . . . . . . . 16 + 5.1. L3VPN Service Delivery . . . . . . . . . . . . . . . . . 16 5.2. VN Lifecycle Management . . . . . . . . . . . . . . . . . 17 - 5.3. Event-based Telemetry in the Device Self management . . . 18 + 5.3. Event-based Telemetry in the Device Self Management . . . 18 6. Security Considerations . . . . . . . . . . . . . . . . . . . 19 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 19 - 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 19 + 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 20 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 10.1. Normative References . . . . . . . . . . . . . . . . . . 20 10.2. Informative References . . . . . . . . . . . . . . . . . 21 - Appendix A. Layered YANG Modules Example Overview . . . . . . . 29 - A.1. Service Models: Definition and Samples . . . . . . . . . 29 - A.2. Network Models: Definitions and Samples . . . . . . . . . 30 - A.3. Device Models: Definitions and Samples . . . . . . . . . 32 - A.3.1. Model Composition . . . . . . . . . . . . . . . . . . 33 - A.3.2. Device Models: Definitions and Samples . . . . . . . 34 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 37 + Appendix A. Layered YANG Modules Examples Overview . . . . . . . 27 + A.1. Service Models: Definition and Samples . . . . . . . . . 27 + A.2. Network Models: Samples . . . . . . . . . . . . . . . . . 28 + A.3. Device Models: Samples . . . . . . . . . . . . . . . . . 30 + A.3.1. Model Composition . . . . . . . . . . . . . . . . . . 31 + A.3.2. Device Models: Samples . . . . . . . . . . . . . . . 32 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 35 1. Introduction The service management system usually comprises service activation/ provision and service operation. Current service delivery procedures, from the processing of customer's requirements and order to service delivery and operation, typically assume the manipulation of data sequentially into multiple OSS/BSS applications that may be managed by different departments within the service provider's organization (e.g., billing factory, design factory, network @@ -148,23 +148,23 @@ can be provided: o Techniques for the dynamic discovery of topology, devices, and capabilities, along with relevant information and data models that are meant to precisely document such topology, devices, and their capabilities. o Techniques for exposing network services [RFC8309] and their characteristics. - o Techniques used by service-requirement-derived dynamic resource - allocation and policy enforcement schemes, so that networks can be - programmed accordingly. + o Techniques used by service-derived dynamic resource allocation and + policy enforcement schemes, so that networks can be programmed + accordingly. o Dynamic feedback mechanisms that are meant to assess how efficiently a given policy (or a set thereof) is enforced from a service fulfillment and assurance perspective. Models are key for each of these technical items. Service and network management automation is an important step to improve the agility of network operations. Models are also important to ease integrating multi-vendor solutions. @@ -186,21 +186,21 @@ YANG modeling technologies and investigates how different layer YANG data models interact with each other (e.g., service mapping, model composing) in the context of service delivery and fulfillment (Section 4). This framework is drawn from a network provider perspective irrespective of the origin of a data module; it can accommodate even modules that are developed outside the IETF. The document identifies a list of use cases to exemplify the proposed - approach (Section 5), but it does not claim to be exhaustive. + approach (Section 5), but it does not claim nor aim to be exhaustive. 2. Terminology The following terms are defined in [RFC8309][RFC8199] and are not redefined here: o Network Operator o Customer @@ -228,21 +228,21 @@ [RFC8519]). 3. Architectural Concepts & Goals 3.1. Data Models: Layering and Representation As described in [RFC8199], layering of modules allows for better reusability of lower-layer modules by higher-level modules while limiting duplication of features across layers. - The data modules can be classified into Service, Network, and Device + The data models can be classified into Service, Network, and Device Models. Different Service Models may rely on the same set of Network and/or Device Models. Service Models traditionally follow top down approach and are mostly customer-facing YANG modules providing a common model construct for higher level network services (e.g., L3VPN), which can be mapped to network technology-specific modules at lower layers (e.g., tunnel, routing, QoS, security). For example, the service level can be used to characterise the network service(s) to be ensured between service nodes (ingress/egress) such as the communication scope (pipe, hose, @@ -299,22 +299,22 @@ * Statistics on aggregate traffic to adjust capacity * Failures * Planned maintenance operations * Triggered by thresholds Figure 2: Sample Attributes Captured in a Service Model Network Models are mainly network resource-facing modules and describe various aspects of a network infrastructure, including devices and their subsystems, and relevant protocols operating at the - link and network layers across multiple devices (e.g., Network - topology and traffic-engineering Tunnel modules). + link and network layers across multiple devices (e.g., network + topology and traffic-engineering tunnel modules). Device (and function) Models usually follow a bottom-up approach and are mostly technology-specific modules used to realize a service (e.g., BGP, NAT). Each level maintains a view of the supported YANG modules provided by low-levels (see for example, Appendix A). Figure 3 illustrates the overall layering model. @@ -347,29 +347,29 @@ | | | | | +-----------------------+ | | | Device | Device Model | | |+--------------------+ | | | || Device Modeling | | Interface add, BGP Peer, | | |+--------------------+ | Tunnel id, QoS/TE | | +-----------------------+ | +-----------------------------------------------------------------+ - Figure 3: Layering and representation + Figure 3: Layering and Representation 3.2. Automation of Service Delivery Procedures Service Models can be used by an operator to expose its services to its customers. Exposing such models allows to automate the - activation and the delivery of service orders. One or more - monolithic Service Models can be used in the context of a composite - service activation request (e.g., delivery of a caching + activation of service orders and thus the service delivery. One or + more monolithic Service Models can be used in the context of a + composite service activation request (e.g., delivery of a caching infrastructure over a VPN). Such modules are used to feed a decision-making intelligence to adequately accommodate customer's needs. Such modules may also be used jointly with services that require dynamic invocation. An example is provided by the service modules defined by the DOTS WG to dynamically trigger requests to handle DDoS attacks [I-D.ietf-dots-signal-channel][I-D.ietf-dots-data-channel]. Network Models can be derived from Service Models and used to @@ -427,21 +427,21 @@ e.g., policies that contain conditions can trigger the generation and pushing of new telemetry data. Performance measurement telemetry can be used to provide service assurance at Service and/or Network levels. Performance measurement telemetry model can tie with Service or Network Models to monitor network performance or Service Level Agreement. 4. Functional Bocks and Interactions - The architectural considerations described in Section 3 lead to the + The architectural considerations described in Section 3 led to the architecture described in this section and illustrated in Figure 4. +------------------+ Service level | | ----------- V | E2E E2E E2E E2E Service -- Service --------> Service --->Service ---+ Exposure Creation ^ Optimization | Diagnosis | /Modification | | | | |Diff | V @@ -588,27 +588,28 @@ o IP layer (IPv4, IPv6) o QoS features such as classification, profiles, etc. o Routing protocols: support of configuration of all protocols listed in the document, as well as routing policies associated with those protocols. o Multicast Support - o NAT or address sharing + o Address sharing o Security function - This specific configuration models can be used to configure PE and CE - devices within the site, e.g., a BGP policy model can be used to - establish VPN membership between sites and VPN Service Topology. + This specific configuration models can be used to configure Provider + Edge (PE) and Customer Edge (CE) devices within the site, e.g., a BGP + policy model can be used to establish VPN membership between sites + and VPN Service Topology. 4.2.2. Configuration Validation Configuration validation is used to validate intended configuration and ensure the configuration take effect. For example, a customer creates an interface "et-0/0/0" but the interface does not physically exist at this point, then configuration data appears in the status but does not appear in datastore. 4.2.3. Performance Monitoring/Model-driven Telemetry @@ -623,22 +624,22 @@ the current status of the network. The management system should subscribe to updates of a YANG datastore in all the network devices for performance monitoring purpose and build full topological visibility to the network by aggregating and filtering these operational state from different sources. 4.2.4. Fault Diagnostic When configuration is in effect in the device, some device may be - misconfigured(e.g.,device links are not consistent on both sides of - the network connection), network resources be misallocated and + mis-configured(e.g.,device links are not consistent on both sides of + the network connection), network resources be mis-allocated and services may be negatively affected without knowing what is going on in the network. Technology-dependent nodes and RPC commands are defined in technology-specific YANG data models which can use and extend the base model described in Section 4.1.4can be used to deal with these challenges. These RPC commands received in the technology dependent node can be used to trigger technology specific OAM message exchange for fault @@ -779,21 +781,21 @@ between source and destination endpoints (service creation operation in Section 4.1.2). 4. The telemetry model which augments the TEAS VN model and corresponding TE Tunnel model can be used to subscribe to performance measurement data and notify all the parameter changes and network performance change related to VN topology or Tunnel [I-D.ietf-teas-actn-pm-telemetry-autonomics] and provide service assurance (service optimization operation in Section 4.1.3). -5.3. Event-based Telemetry in the Device Self management +5.3. Event-based Telemetry in the Device Self Management +----------------+ | | | Controller | +----------------+ | | ECA | Model| ^ | |Notif @@ -811,22 +813,22 @@ In reference to Figure 7, the following steps are performed to monitor state changes of managed objects or resource in the device and provide device self management within the network management automation architecture defined in this document: 1. To control which state a network device should be in or is allowed to be in at any given time, a set of conditions and actions are defined and correlated with network events (e.g., allow the NETCONF server send updates only when the value exceeds a certain threshold for the first time but not again until the - threshold is cleared.), which constitute an event-driven policy - or network control logic in the controller. + threshold is cleared), which constitute an event-driven policy or + network control logic in the controller. 2. The controller pushes ECA policy to the network device and delegate network control logic to the network device. 3. The network device generates ECA script from ECA model and execute ECA script or network control logic based on Event. Event based notification or telemetry can be triggered if a certain condition is satisfied (model driven telemetry operation in Section 4.2.3). @@ -895,43 +898,20 @@ 10. References 10.1. Normative References [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . 10.2. Informative References - [I-D.arkko-arch-virtualization] - Arkko, J., Tantsura, J., Halpern, J., and B. Varga, - "Considerations on Network Virtualization and Slicing", - draft-arkko-arch-virtualization-01 (work in progress), - March 2018. - - [I-D.asechoud-netmod-diffserv-model] - Choudhary, A., Shah, S., Jethanandani, M., Liu, B., and N. - Strahle, "YANG Model for Diffserv", draft-asechoud-netmod- - diffserv-model-03 (work in progress), June 2015. - - [I-D.clacla-netmod-model-catalog] - Clarke, J. and B. Claise, "YANG module for - yangcatalog.org", draft-clacla-netmod-model-catalog-03 - (work in progress), April 2018. - - [I-D.homma-slice-provision-models] - Homma, S., Nishihara, H., Miyasaka, T., Galis, A., OV, V., - Lopez, D., Contreras, L., Ordonez-Lucena, J., Martinez- - Julia, P., Qiang, L., Rokui, R., Ciavaglia, L., and X. - Foy, "Network Slice Provision Models", draft-homma-slice- - provision-models-02 (work in progress), November 2019. - [I-D.ietf-bess-evpn-yang] Brissette, P., Shah, H., Hussain, I., Tiruveedhula, K., and J. Rabadan, "Yang Data Model for EVPN", draft-ietf- bess-evpn-yang-07 (work in progress), March 2019. [I-D.ietf-bess-l2vpn-yang] Shah, H., Brissette, P., Chen, I., Hussain, I., Wen, B., and K. Tiruveedhula, "YANG Data Model for MPLS-based L2VPN", draft-ietf-bess-l2vpn-yang-10 (work in progress), July 2019. @@ -941,202 +921,127 @@ Liu, X., Haas, J., Esale, S., and B. Wen, "Yang Data Model for BGP/MPLS L3 VPNs", draft-ietf-bess-l3vpn-yang-04 (work in progress), October 2018. [I-D.ietf-bfd-yang] Rahman, R., Zheng, L., Jethanandani, M., Pallagatti, S., and G. Mirsky, "YANG Data Model for Bidirectional Forwarding Detection (BFD)", draft-ietf-bfd-yang-17 (work in progress), August 2018. - [I-D.ietf-ccamp-alarm-module] - Vallin, S. and M. Bjorklund, "YANG Alarm Module", draft- - ietf-ccamp-alarm-module-09 (work in progress), April 2019. - - [I-D.ietf-ccamp-flexigrid-media-channel-yang] - Madrid, U., Perdices, D., Lopezalvarez, V., Dios, O., - King, D., Lee, Y., and G. Galimberti, "YANG data model for - Flexi-Grid media-channels", draft-ietf-ccamp-flexigrid- - media-channel-yang-02 (work in progress), March 2019. - - [I-D.ietf-ccamp-flexigrid-yang] - Madrid, U., Perdices, D., Lopezalvarez, V., King, D., Lee, - Y., and H. Zheng, "YANG data model for Flexi-Grid Optical - Networks", draft-ietf-ccamp-flexigrid-yang-05 (work in - progress), January 2020. - - [I-D.ietf-ccamp-l1csm-yang] - Lee, Y., Lee, K., Zheng, H., Dhody, D., Dios, O., and D. - Ceccarelli, "A YANG Data Model for L1 Connectivity Service - Model (L1CSM)", draft-ietf-ccamp-l1csm-yang-10 (work in - progress), September 2019. - - [I-D.ietf-ccamp-mw-yang] - Ahlberg, J., Ye, M., Li, X., Spreafico, D., and M. - Vaupotic, "A YANG Data Model for Microwave Radio Link", - draft-ietf-ccamp-mw-yang-13 (work in progress), November - 2018. - - [I-D.ietf-ccamp-otn-topo-yang] - Zheng, H., Busi, I., Liu, X., Belotti, S., and O. Dios, "A - YANG Data Model for Optical Transport Network Topology", - draft-ietf-ccamp-otn-topo-yang-09 (work in progress), - November 2019. - - [I-D.ietf-ccamp-otn-tunnel-model] - Zheng, H., Busi, I., Belotti, S., Lopezalvarez, V., and Y. - Xu, "OTN Tunnel YANG Model", draft-ietf-ccamp-otn-tunnel- - model-09 (work in progress), November 2019. - - [I-D.ietf-ccamp-wson-tunnel-model] - Lee, Y., Zheng, H., Guo, A., Lopezalvarez, V., King, D., - Yoon, B., and R. Vilata, "A Yang Data Model for WSON - Tunnel", draft-ietf-ccamp-wson-tunnel-model-04 (work in - progress), September 2019. - [I-D.ietf-dots-data-channel] Boucadair, M. and T. Reddy.K, "Distributed Denial-of- Service Open Threat Signaling (DOTS) Data Channel Specification", draft-ietf-dots-data-channel-31 (work in progress), July 2019. [I-D.ietf-dots-signal-channel] Reddy.K, T., Boucadair, M., Patil, P., Mortensen, A., and N. Teague, "Distributed Denial-of-Service Open Threat Signaling (DOTS) Signal Channel Specification", draft- ietf-dots-signal-channel-41 (work in progress), January 2020. + [I-D.ietf-i2rs-yang-l2-network-topology] + Dong, J., Wei, X., WU, Q., Boucadair, M., and A. Liu, "A + YANG Data Model for Layer-2 Network Topologies", draft- + ietf-i2rs-yang-l2-network-topology-13 (work in progress), + March 2020. + [I-D.ietf-idr-bgp-model] Jethanandani, M., Patel, K., Hares, S., and J. Haas, "BGP YANG Model for Service Provider Networks", draft-ietf-idr- - bgp-model-07 (work in progress), October 2019. + bgp-model-08 (work in progress), February 2020. [I-D.ietf-ippm-stamp-yang] Mirsky, G., Xiao, M., and W. Luo, "Simple Two-way Active Measurement Protocol (STAMP) Data Model", draft-ietf-ippm- stamp-yang-05 (work in progress), October 2019. [I-D.ietf-ippm-twamp-yang] Civil, R., Morton, A., Rahman, R., Jethanandani, M., and K. Pentikousis, "Two-Way Active Measurement Protocol (TWAMP) Data Model", draft-ietf-ippm-twamp-yang-13 (work in progress), July 2018. [I-D.ietf-mpls-base-yang] Saad, T., Raza, K., Gandhi, R., Liu, X., and V. Beeram, "A YANG Data Model for MPLS Base", draft-ietf-mpls-base- - yang-12 (work in progress), February 2020. + yang-14 (work in progress), March 2020. [I-D.ietf-pim-igmp-mld-snooping-yang] Zhao, H., Liu, X., Liu, Y., Sivakumar, M., and A. Peter, "A Yang Data Model for IGMP and MLD Snooping", draft-ietf- pim-igmp-mld-snooping-yang-09 (work in progress), January 2020. - [I-D.ietf-pim-igmp-mld-yang] - Liu, X., Guo, F., Sivakumar, M., McAllister, P., and A. - Peter, "A YANG Data Model for Internet Group Management - Protocol (IGMP) and Multicast Listener Discovery (MLD)", - draft-ietf-pim-igmp-mld-yang-15 (work in progress), June - 2019. - [I-D.ietf-pim-yang] Liu, X., McAllister, P., Peter, A., Sivakumar, M., Liu, Y., and f. hu, "A YANG Data Model for Protocol Independent Multicast (PIM)", draft-ietf-pim-yang-17 (work in progress), May 2018. [I-D.ietf-rtgwg-device-model] Lindem, A., Berger, L., Bogdanovic, D., and C. Hopps, "Network Device YANG Logical Organization", draft-ietf- rtgwg-device-model-02 (work in progress), March 2017. [I-D.ietf-rtgwg-policy-model] Qu, Y., Tantsura, J., Lindem, A., and X. Liu, "A YANG Data Model for Routing Policy Management", draft-ietf-rtgwg- - policy-model-08 (work in progress), January 2020. - - [I-D.ietf-softwire-iftunnel] - Boucadair, M., Farrer, I., and R. Asati, "Tunnel Interface - Types YANG Module", draft-ietf-softwire-iftunnel-07 (work - in progress), June 2019. + policy-model-09 (work in progress), March 2020. - [I-D.ietf-softwire-yang] - Farrer, I. and M. Boucadair, "YANG Modules for IPv4-in- - IPv6 Address plus Port (A+P) Softwires", draft-ietf- - softwire-yang-16 (work in progress), January 2019. + [I-D.ietf-rtgwg-qos-model] + Choudhary, A., Jethanandani, M., Strahle, N., Aries, E., + and I. Chen, "YANG Model for QoS", draft-ietf-rtgwg-qos- + model-00 (work in progress), October 2019. [I-D.ietf-spring-sr-yang] Litkowski, S., Qu, Y., Lindem, A., Sarkar, P., and J. Tantsura, "YANG Data Model for Segment Routing", draft- ietf-spring-sr-yang-15 (work in progress), January 2020. [I-D.ietf-supa-generic-policy-data-model] Halpern, J. and J. Strassner, "Generic Policy Data Model for Simplified Use of Policy Abstractions (SUPA)", draft- ietf-supa-generic-policy-data-model-04 (work in progress), June 2017. [I-D.ietf-teas-actn-pm-telemetry-autonomics] Lee, Y., Dhody, D., Karunanithi, S., Vilata, R., King, D., and D. Ceccarelli, "YANG models for VN/TE Performance Monitoring Telemetry and Scaling Intent Autonomics", - draft-ietf-teas-actn-pm-telemetry-autonomics-01 (work in - progress), October 2019. + draft-ietf-teas-actn-pm-telemetry-autonomics-02 (work in + progress), March 2020. [I-D.ietf-teas-actn-vn-yang] Lee, Y., Dhody, D., Ceccarelli, D., Bryskin, I., and B. Yoon, "A Yang Data Model for VN Operation", draft-ietf- - teas-actn-vn-yang-07 (work in progress), October 2019. - - [I-D.ietf-teas-sf-aware-topo-model] - Bryskin, I., Liu, X., Lee, Y., Guichard, J., Contreras, - L., Ceccarelli, D., and J. Tantsura, "SF Aware TE Topology - YANG Model", draft-ietf-teas-sf-aware-topo-model-04 (work - in progress), November 2019. - - [I-D.ietf-teas-te-service-mapping-yang] - Lee, Y., Dhody, D., Fioccola, G., WU, Q., Ceccarelli, D., - and J. Tantsura, "Traffic Engineering (TE) and Service - Mapping Yang Model", draft-ietf-teas-te-service-mapping- - yang-02 (work in progress), September 2019. - - [I-D.ietf-teas-yang-l3-te-topo] - Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and - O. Dios, "YANG Data Model for Layer 3 TE Topologies", - draft-ietf-teas-yang-l3-te-topo-05 (work in progress), - July 2019. + teas-actn-vn-yang-08 (work in progress), March 2020. [I-D.ietf-teas-yang-path-computation] Busi, I., Belotti, S., Lopezalvarez, V., Sharma, A., and Y. Shi, "Yang model for requesting Path Computation", draft-ietf-teas-yang-path-computation-08 (work in progress), December 2019. [I-D.ietf-teas-yang-rsvp-te] Beeram, V., Saad, T., Gandhi, R., Liu, X., Bryskin, I., and H. Shah, "A YANG Data Model for RSVP-TE Protocol", - draft-ietf-teas-yang-rsvp-te-07 (work in progress), July - 2019. - - [I-D.ietf-teas-yang-sr-te-topo] - Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and - S. Litkowski, "YANG Data Model for SR and SR TE - Topologies", draft-ietf-teas-yang-sr-te-topo-06 (work in - progress), November 2019. + draft-ietf-teas-yang-rsvp-te-08 (work in progress), March + 2020. [I-D.ietf-teas-yang-te] Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin, "A YANG Data Model for Traffic Engineering Tunnels and - Interfaces", draft-ietf-teas-yang-te-22 (work in - progress), November 2019. + Interfaces", draft-ietf-teas-yang-te-23 (work in + progress), March 2020. [I-D.ietf-teas-yang-te-topo] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and O. Dios, "YANG Data Model for Traffic Engineering (TE) Topologies", draft-ietf-teas-yang-te-topo-22 (work in progress), June 2019. [I-D.ietf-trill-yang-oam] Kumar, D., Senevirathne, T., Finn, N., Salam, S., Xia, L., and H. Weiguo, "YANG Data Model for TRILL Operations, @@ -1285,53 +1190,62 @@ RFC 8532, DOI 10.17487/RFC8532, April 2019, . [RFC8533] Kumar, D., Wang, M., Wu, Q., Ed., Rahman, R., and S. Raghavan, "A YANG Data Model for Retrieval Methods for the Management of Operations, Administration, and Maintenance (OAM) Protocols That Use Connectionless Communications", RFC 8533, DOI 10.17487/RFC8533, April 2019, . -Appendix A. Layered YANG Modules Example Overview + [RFC8675] Boucadair, M., Farrer, I., and R. Asati, "A YANG Data + Model for Tunnel Interface Types", RFC 8675, + DOI 10.17487/RFC8675, November 2019, + . - It is not the intent of this document to provide an inventory of + [RFC8676] Farrer, I., Ed. and M. Boucadair, Ed., "YANG Modules for + IPv4-in-IPv6 Address plus Port (A+P) Softwires", RFC 8676, + DOI 10.17487/RFC8676, November 2019, + . + +Appendix A. Layered YANG Modules Examples Overview + + It is not the intent of this appendix to provide an inventory of tools and mechanisms used in specific network and service management domains; such inventory can be found in documents such as [RFC7276]. A.1. Service Models: Definition and Samples As described in [RFC8309], the service is "some form of connectivity between customer sites and the Internet and/or between customer sites across the network operator's network and across the Internet". More concretely, an IP connectivity service can be defined as the IP transfer capability characterized by a (Source Nets, Destination Nets, Guarantees, Scope) tuple where "Source Nets" is a group of unicast IP addresses, "Destination Nets" is a group of IP unicast and/or multicast addresses, and "Guarantees" reflects the guarantees (expressed in terms of Quality Of Service (QoS), performance, and availability, for example) to properly forward traffic to the said "Destination" [RFC7297]. For example: - o L3SM model [RFC8299] defines the L3VPN service ordered by a + o The L3SM model [RFC8299] defines the L3VPN service ordered by a customer from a network operator. - o L2SM model [RFC8466] defines the L2VPN service ordered by a + o The L2SM model [RFC8466] defines the L2VPN service ordered by a customer from a network operator. - o VN model [I-D.ietf-teas-actn-vn-yang]provides a YANG data model - generally applicable to any mode of Virtual Network (VN) - operation. + o The Virtual Network (VN) model [I-D.ietf-teas-actn-vn-yang] + provides a YANG data model applicable to any mode of VN operation. -A.2. Network Models: Definitions and Samples +A.2. Network Models: Samples Figure 8 depicts a set of Network models such as topology models or tunnel models: | | Topo YANG modules | Tunnel YANG modules | ------------------------------------------------| +------------+ | | |Network Top | | +------+ +-----------+ | | Model | | |Other | | TE Tunnel | | @@ -1350,116 +1264,115 @@ +--------+ | Figure 8: Sample Resource Facing Network Models Topology YANG module Examples: o Network Topology Models: [RFC8345] defines a base model for network topology and inventories. Network topology data include link resource, node resource, and terminate-point resources. - o TE Topology Models: [I.D-ietf-teas-yang-te-topo] defines a data + o TE Topology Models: [I-D.ietf-teas-yang-te-topo] defines a data model for representing and manipulating TE topologies. This module is extended from network topology model defined in [RFC8345] with TE topologies specifics. This model contains technology-agnostic TE Topology building blocks that can be augmented and used by other technology-specific TE Topology models. o L3 Topology Models [RFC8346] defines a data model for representing and manipulating - L3 Topologies. This model is extended from the network topology - model defined in [RFC8345] with L3 topologies specifics. + Layer 3 topologies. This model is extended from the network + topology model defined in [RFC8345] with L3 topologies specifics. o L2 Topology Models - [I.D-ietf-i2rs-yang-l2-topology] defines a data model for - representing and manipulating L2 Topologies. This model is + [I-D.ietf-i2rs-yang-l2-network-topology] defines a data model for + representing and manipulating L2 topologies. This model is extended from the network topology model defined in [RFC8345] with - L2 topologies specifics. + Layer 2 topologies specifics. Tunnel YANG module Examples: - o Tunnel identities [I-D.ietf-softwire-iftunnel] to ease - manipulating extensions to specific tunnels. + o Tunnel identities to ease manipulating extensions to specific + tunnels [RFC8675]. - o TE Tunnel Model + o TE Tunnel Model: - [I.D-ietf-teas-yang-te] defines a YANG module for the - configuration and management of TE interfaces, tunnels and LSPs. + [I-D.ietf-teas-yang-te] defines a YANG module for the + configuration and management of TE interfaces, tunnels, and LSPs. - o SR TE Tunnel Model + o SR TE Tunnel Model: - [I.D-ietf-teas-yang-te] augments the TE generic and MPLS-TE + [I-D.ietf-teas-yang-te] augments the TE generic and MPLS-TE model(s) and defines a YANG module for Segment Routing (SR) TE specific data. - o MPLS TE Model + o MPLS TE Model: - [I.D-ietf-teas-yang-te] augments the TE generic and MPLS-TE + [I-D.ietf-teas-yang-te] augments the TE generic and MPLS-TE model(s) and defines a YANG module for MPLS TE configurations, state, RPC and notifications. - o RSVP-TE MPLS Model + o RSVP-TE MPLS Model: - [I.D-ietf-teas-yang-rsvp-te] augments the RSVP-TE generic module + [I-D.ietf-teas-yang-rsvp-te] augments the RSVP-TE generic module with parameters to configure and manage signaling of MPLS RSVP-TE LSPs. Other Network Models: - o Path Computation API Model + o Path Computation API Model: - [I.D-ietf-teas-path-computation] YANG module for a stateless RPC - which complements the stateful solution defined in [I.D-ietf-teas- - yang-te]. + [I-D.ietf-teas-yang-path-computation] YANG module for a stateless + RPC which complements the stateful solution defined in + [I-D.ietf-teas-yang-te]. o OAM Models (including Fault Management (FM) and Performance - Monitoring) + Monitoring): [RFC8532] defines a base YANG module for the management of OAM protocols that use Connectionless Communications. [RFC8533] defines a retrieval method YANG module for connectionless OAM protocols. [RFC8531] defines a base YANG module for connection oriented OAM protocols. These three models are intended to - provide consistent reporting, configuration and representation for - connection-less OAM and Connection oriented OAM separately. + provide consistent reporting, configuration, and representation + for connection-less OAM and Connection oriented OAM separately. Alarm monitoring is a fundamental part of monitoring the network. Raw alarms from devices do not always tell the status of the - network services or necessarily point to the root cause. [I.D- - ietf-ccamp-alarm-module] defines a YANG module for alarm - management. + network services or necessarily point to the root cause. RFC8632 + defines a YANG module for alarm management. - o Generic Policy Model + o Generic Policy Model: The Simplified Use of Policy Abstractions (SUPA) policy-based management framework [RFC8328] defines base YANG modules [I-D.ietf-supa-generic-policy-data-model]to encode policy. These - models point to device-, technology-, and service-specific YANG - modules developed elsewhere. Policy rules within an operator's - environment can be used to express high-level, possibly network- - wide, policies to a network management function (within a - controller, an orchestrator, or a network element). The network - management function can then control the configuration and/or - monitoring of network elements and services. This document - describes the SUPA basic framework, its elements, and interfaces. + models point to other device-, technology-, and service-specific + YANG modules. Policy rules within an operator's environment can + be used to express high-level, possibly network-wide, policies to + a network management function (within a controller, an + orchestrator, or a network element). The network management + function can then control the configuration and/or monitoring of + network elements and services. This document describes the SUPA + basic framework, its elements, and interfaces. -A.3. Device Models: Definitions and Samples +A.3. Device Models: Samples Network Element models (Figure 9) are used to describe how a service can be implemented by activating and tweaking a set of functions (enabled in one or multiple devices, or hosted in cloud - infrastructures) that are involved in the service delivery. The - following figure uses IETF defined models as an example. + infrastructures) that are involved in the service delivery. Figure 9 + uses IETF-defined models as an example. +----------------+ --|Device Model | | +----------------+ | +------------------+ +---------------+ | |Logical Network | | | --| Element Mode | | Architecture | | +------------------+ | | | +----------------------+ +-------+-------+ --|Network Instance Mode | @@ -1492,21 +1405,21 @@ | +-------+ --|OSPF-SR| +-------+ Figure 9: Network Element Modules Overview A.3.1. Model Composition o Device Model - [I.D-ietf-rtgwg-device-model] presents an approach for organizing + [I-D.ietf-rtgwg-device-model] presents an approach for organizing YANG modules in a comprehensive logical structure that may be used to configure and operate network devices. The structure is itself represented as an example YANG module, with all of the related component models logically organized in a way that is operationally intuitive, but this model is not expected to be implemented. o Logical Network Element Model [RFC8530] defines a logical network element module which can be @@ -1529,127 +1442,126 @@ of the YANG data modeling language. As a result, the same YANG module can be combined with various sets of other modules and thus form a data model that is tailored to meet the requirements of a specific use case. [RFC8528] defines a mechanism, denoted schema mount, that allows for mounting one data model consisting of any number of YANG modules at a specified location of another (parent) schema. That capability does not cover design time. -A.3.2. Device Models: Definitions and Samples +A.3.2. Device Models: Samples - BGP: [I-D.ietf-idr-bgp-yang-model] defines a YANG module for + The following provides an overview of some device models that can be + used within a network. This list is not comprehensive. + + BGP: [I-D.ietf-idr-bgp-model] defines a YANG module for configuring and managing BGP, including protocol, policy, - and operational aspects based on data center, carrier and + and operational aspects based on data center, carrier, and content provider operational requirements. MPLS: [I-D.ietf-mpls-base-yang] defines a base model for MPLS which serves as a base framework for configuring and managing an MPLS switching subsystem. It is expected that - other MPLS technology YANG modules (e.g. MPLS LSP Static, + other MPLS technology YANG modules (e.g., MPLS LSP Static, LDP or RSVP-TE models) will augment the MPLS base YANG module. - QoS: [I-D.asechoud-netmod-diffserv-model] describes a YANG - module of Differentiated Services for configuration and - operations. + QoS: [I-D.ietf-rtgwg-qos-model] describes a YANG module of + Differentiated Services for configuration and operations. ACL: Access Control List (ACL) is one of the basic elements used to configure device forwarding behavior. It is used in many networking technologies such as Policy Based Routing, Firewalls, etc. [RFC8519] describes a data model - of Access Control List (ACL) basic building blocks. + of ACL basic building blocks. NAT: For the sake of network automation and the need for programming Network Address Translation (NAT) function in particular, a data model for configuring and managing the NAT is essential. [RFC8512] defines a YANG module for the NAT function covering a variety of NAT flavors such as Network Address Translation from IPv4 to IPv4 (NAT44), Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers (NAT64), customer-side translator (CLAT), Stateless IP/ICMP Translation (SIIT), Explicit Address Mappings (EAM) for SIIT, IPv6-to-IPv6 Network Prefix Translation (NPTv6), and Destination NAT. [RFC8513] - specifies a YANG module for the DS-Lite AFTR. + specifies a DS-Lite YANG module. - Stateless Address Sharing: [I-D.ietf-softwire-yang] specifies a YANG - module for A+P address sharing, including Lightweight - 4over6, Mapping of Address and Port with Encapsulation - (MAP-E), and Mapping of Address and Port using Translation - (MAP-T) softwire mechanisms. + Stateless Address Sharing: [RFC8676] specifies a YANG module for A+P + address sharing, including Lightweight 4over6, Mapping of + Address and Port with Encapsulation (MAP-E), and Mapping + of Address and Port using Translation (MAP-T) softwire + mechanisms. Multicast: [I-D.ietf-pim-yang] defines a YANG module that can be used to configure and manage Protocol Independent Multicast - (PIM) devices. [I-D.ietf-pim-igmp-mld-yang] defines a - YANG module that can be used to configure and manage - Internet Group Management Protocol (IGMP) and Multicast - Listener Discovery (MLD) devices. [I-D.ietf-pim-igmp-mld- - snooping-yang] defines a YANG module that can be used to + (PIM) devices. + + RFC8652 defines a YANG module that can be used to configure and manage Internet Group Management Protocol - (IGMP) and Multicast Listener Discovery (MLD) Snooping - devices. + (IGMP) and Multicast Listener Discovery (MLD) devices. + + [I-D.ietf-pim-igmp-mld-snooping-yang] defines a YANG + module that can be used to configure and manage Internet + Group Management Protocol (IGMP) and Multicast Listener + Discovery (MLD) Snooping devices. EVPN: [I-D.ietf-bess-evpn-yang] defines a YANG module for Ethernet VPN services. The model is agnostic of the - underlay. It apply to MPLS as well as to VxLAN - encapsulation. The model is also agnostic of the services - including E-LAN, E-LINE and E-TREE services. This - document mainly focuses on EVPN and Ethernet-Segment - instance framework. + underlay. It applies to MPLS as well as to VxLAN + encapsulation. The module is also agnostic to the + services, including E-LAN, E-LINE, and E-TREE services. L3VPN: [I-D.ietf-bess-l3vpn-yang] defines a YANG module that can be used to configure and manage BGP L3VPNs [RFC4364]. It contains VRF specific parameters as well as BGP specific parameters applicable for L3VPNs. L2VPN: [I-D.ietf-bess-l2vpn-yang] defines a YANG module for MPLS based Layer 2 VPN services (L2VPN) [RFC4664] and includes switching between the local attachment circuits. The L2VPN model covers point-to-point VPWS and Multipoint VPLS services. These services use signaling of Pseudowires across MPLS networks using LDP [RFC8077][RFC4762] or BGP [RFC4761]. Routing Policy: [I-D.ietf-rtgwg-policy-model] defines a YANG module - for configuring and managing routing policies in a vendor- - neutral way and based on actual operational practice. The - model provides a generic policy framework which can be - augmented with protocol-specific policy configuration. + for configuring and managing routing policies based on + operational practice. The module provides a generic + policy framework which can be augmented with protocol- + specific policy configuration. - BFD: [I-D.ietf-bfd-yang]defines a YANG module that can be used - to configure and manage Bidirectional Forwarding Detection - (BFD) [RFC5880]. BFD is a network protocol which is used - for liveness detection of arbitrary paths between systems. + BFD: Bidirectional Forwarding Detection (BFD) [RFC5880] is a + network protocol which is used for liveness detection of + arbitrary paths between systems. [I-D.ietf-bfd-yang] + defines a YANG module that can be used to configure and + manage BFD. SR/SRv6: [I-D.ietf-spring-sr-yang] a YANG module for segment - routing configuration and operation. [I-D.raza-spring- - srv6-yang] defines a YANG module for Segment Routing IPv6 - (SRv6) base. The model serves as a base framework for - configuring and managing an SRv6 subsystem and expected to - be augmented by other SRv6 technology models accordingly. + routing configuration and operation. Core Routing: [RFC8349] defines the core routing data model, which is intended as a basis for future data model development covering more-sophisticated routing systems. It is expected that other Routing technology YANG modules (e.g., VRRP, RIP, ISIS, OSPF models) will augment the Core Routing base YANG module. PM: - [I.D-ietf-ippm-twamp-yang] defines a data model for client + [I-D.ietf-ippm-twamp-yang] defines a data model for client and server implementations of the Two-Way Active Measurement Protocol (TWAMP). - [I.D-ietf-ippm-stamp-yang] defines the data model for + [I-D.ietf-ippm-stamp-yang] defines the data model for implementations of Session-Sender and Session-Reflector for Simple Two-way Active Measurement Protocol (STAMP) mode using YANG. [RFC8194] defines a data model for Large-Scale Measurement Platforms (LMAPs). Authors' Addresses Qin Wu (editor)