ccamp J. Ahlberg Internet-Draft S. Mansfield Intended status: Standards Track Ericsson Expires: 7 September 2023 M. Ye I. Busi Huawei Technologies X. Li NEC Laboratories Europe D. Spreafico Nokia - IT 6 March 2023 A YANG Data Model for Bandwidth Availability Topology draft-ietf-ccamp-bwa-topo-yang-00 Abstract This document defines a YANG data model to describe bandwidth availability for a link in a network topology. Discussion Venues This note is to be removed before publishing as an RFC. Source for this draft and an issue tracker can be found at https://github.com/ietf-ccamp-wg/draft-ietf-ccamp-mw-topo-yang. 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 September 2023. Ahlberg, et al. Expires 7 September 2023 [Page 1] Internet-Draft BWA Topo YANG Model March 2023 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. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Terminology and Definitions . . . . . . . . . . . . . . . 3 1.2. Tree Structure . . . . . . . . . . . . . . . . . . . . . 3 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3 3. Bandwidth Availability Topology YANG Data Model . . . . . . . 3 3.1. YANG Tree . . . . . . . . . . . . . . . . . . . . . . . . 3 3.2. Bandwidth Availability Topology YANG Data Module . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 6.1. Normative References . . . . . . . . . . . . . . . . . . 8 6.2. Informative References . . . . . . . . . . . . . . . . . 9 Appendix A. Examples of the application of the Bandwidth Availability Topology Model . . . . . . . . . . . . . . . 9 A.1. A tree for a the Bandwidth Availability Topology Model . 10 A.2. A JSON example . . . . . . . . . . . . . . . . . . . . . 10 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 1. Introduction This document defines a YANG data model to describe bandwidth availability for a link. It is an important characteristic of links with variable bandwidth, where each level of bandwidth can be associated with a certain level of availability. An example of such a link is microwave radio link, where the bandwidth can be dynamically adapted to changing signal conditions, impacted by interference & fading, in order to guarantee the required quality of the link at every single moment. [RFC8330] defines a mechanism to report bandwidth-availability information through OSPF-TE, but it could also be useful for a controller to access such bandwidth- availability information as part of the topology model when Ahlberg, et al. Expires 7 September 2023 [Page 2] Internet-Draft BWA Topo YANG Model March 2023 performing a path/route computation. The model augments "YANG Data Model for Traffic Engineering (TE) Topologies" defined in [RFC8795], which is based on "A YANG Data Model for Network Topologies" defined in [RFC8345]. The bandwidth availability model is expected to be used between a Provisioning Network Controller (PNC) and a Multi Domain Service Coordinator(MDSC) [RFC8453]. Examples of use cases that can be supported are: 1. Propagation of relevant characteristics of a link, including bandwidth availability, to higher topology layers, where it e.g. could be used as a criterion when configuring and optimizing a path for a connection/service through the network end to end. 2. A link could dynamically adjust its bandwidth according to changes in the signal conditions. [RFC8330] defines a mechanism to report bandwidth-availability information through OSPF-TE, but it could also be useful for a controller to access such bandwidth-availability information as part of the topology model when performing a path/route computation. 1.1. Terminology and Definitions The following acronyms are used in this document: PNC Provisioning Network Controller MDSC Multi Domain Service Coordinator 1.2. Tree Structure A simplified graphical representation of the data model is used in chapter 3.1 of this document. The meaning of the symbols in these diagrams is defined in [RFC8340]. 2. Requirements Language 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. 3. Bandwidth Availability Topology YANG Data Model 3.1. YANG Tree Ahlberg, et al. Expires 7 September 2023 [Page 3] Internet-Draft BWA Topo YANG Model March 2023 module: ietf-bandwidth-availability-topology augment /nw:networks/nw:network/nt:link/tet:te /tet:te-link-attributes: +---u link-bw-availability-table 3.2. Bandwidth Availability Topology YANG Data Module file "ietf-bandwidth-availability-topology.yang" module ietf-bandwidth-availability-topology { yang-version "1.1"; namespace "urn:ietf:params:xml:ns:yang:ietf-bandwidth-availability-topology"; prefix "bwatopo"; import ietf-yang-types { prefix yang; reference "RFC 6991"; } import ietf-network { prefix "nw"; reference "RFC 8345: A YANG Data Model for Network Topologies"; } import ietf-network-topology { prefix "nt"; reference "RFC 8345: A YANG Data Model for Network Topologies"; } import ietf-te-topology { prefix "tet"; reference "RFC 8795: YANG Data Model for Traffic Engineering (TE) Topologies"; } organization "Internet Engineering Task Force (IETF) CCAMP WG"; contact "WG List: Editor: Jonas Ahlberg Editor: Scott Mansfield Editor: Min Ye Ahlberg, et al. Expires 7 September 2023 [Page 4] Internet-Draft BWA Topo YANG Model March 2023 Editor: Italo Busi Editor: Xi Li Editor: Daniela Spreafico "; description "This is a module for defining bandwidth availability matrix, for links in a topology. It is intended to be used in conjunction with an instance of ietf-network-topology and its augmentations. Example use cases include: - Defining bandwidth availability matrix for a microwave link - Defining bandwidth availability matrix for a LAG link comprising of two or more member links 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 (https://tools.ietf.org/html/rfcXXXX); see the RFC itself for full legal notices."; revision 2023-02-15 { description "First rough draft."; reference ""; } /* * Groupings */ grouping link-bw-availability-table { description "Grouping used for bandwidth availability."; list link-availability{ key "availability"; Ahlberg, et al. Expires 7 September 2023 [Page 5] Internet-Draft BWA Topo YANG Model March 2023 description "Table describing the bandwidths available at corresponding availability level for a link."; leaf availability { type decimal64 { fraction-digits 4; range "0..99.9999"; } description "Availability level"; } leaf link-bandwidth { type uint64; units "Kbps"; description "The link bandwidth corresponding to the availability level"; } } leaf actual-bandwidth{ type yang:gauge64; units "bits/second"; config false; description "An estimate of the link's current bandwidth in bits per second. Related to the data node speed in RFC 8343."; reference "RFC 8343: A YANG Data Model for Interface Management"; } } /* * Data nodes */ augment "/nw:networks/nw:network/nt:link/tet:te/" + "tet:te-link-attributes" { description "Augmenting link with link bandwidth availability matrix."; uses link-bw-availability-table; } } Ahlberg, et al. Expires 7 September 2023 [Page 6] Internet-Draft BWA Topo YANG Model March 2023 4. Security Considerations The YANG module specified in this document defines schemas 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 access control model [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. The YANG module specified in this document imports and augments the ietf-network and ietf-network-topology models defined in [RFC8345]. The security considerations from [RFC8345] are applicable to the module in this document. There are a several 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 or vulnerable 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 data nodes and their sensitivity/vulnerability: In the "ietf-bandwidth-availability-topology" module: * availability: A malicious client could attempt to modify the availability level which could modify the intended behavior. * link-bandwidth: A malicious client could attempt to modify the link bandwidth which could either provide more or less link bandwidth at the indicated availability level, changing the resource allocation in unintended ways. 5. IANA Considerations IANA is asked to assign a new URI from the "IETF XML Registry" [RFC3688] as follows: URI: urn:ietf:params:xml:ns:yang:ietf-bandwidth-availability-topology Registrant Contact: The IESG XML: N/A; the requested URI is an XML namespace. Ahlberg, et al. Expires 7 September 2023 [Page 7] Internet-Draft BWA Topo YANG Model March 2023 It is proposed that IANA should record YANG module names in the "YANG Module Names" registry [RFC6020] as follows: Name: ietf-bandwidth-availability-topology Maintained by IANA?: N Namespace: urn:ietf:params:xml:ns:yang:ietf-bandwidth-availability-topology Prefix: bwavtopo Reference: RFC XXXX 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, . [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, . [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, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . Ahlberg, et al. Expires 7 September 2023 [Page 8] Internet-Draft BWA Topo YANG Model March 2023 [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . [RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N., Ananthakrishnan, H., and X. Liu, "A YANG Data Model for Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March 2018, . [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . [RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and O. Gonzalez de Dios, "YANG Data Model for Traffic Engineering (TE) Topologies", RFC 8795, DOI 10.17487/RFC8795, August 2020, . 6.2. Informative References [RFC8330] Long, H., Ye, M., Mirsky, G., D'Alessandro, A., and H. Shah, "OSPF Traffic Engineering (OSPF-TE) Link Availability Extension for Links with Variable Discrete Bandwidth", RFC 8330, DOI 10.17487/RFC8330, February 2018, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8453] Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for Abstraction and Control of TE Networks (ACTN)", RFC 8453, DOI 10.17487/RFC8453, August 2018, . Appendix A. Examples of the application of the Bandwidth Availability Topology Model This appendix provides some examples and illustrations of how the Bandwidth Availability Topology Model can be used. There is one extended tree to illustrate the model and a JSON based instantiation for a small network example. Ahlberg, et al. Expires 7 September 2023 [Page 9] Internet-Draft BWA Topo YANG Model March 2023 A.1. A tree for a the Bandwidth Availability Topology Model The tree below shows the leafs for the Bandwidth Availability Model including the augmented Network Topology Model defined in [RFC8345] and Traffic Engineering (TE) Topologies model defined in [RFC8795]. module: ietf-network +--rw networks +--rw network* [network-id] +--rw network-id network-id +--rw nt:link* [link-id] +--rw nt:link-id link-id +--rw tet:te! +--rw tet:te-link-attributes +--rw bwatopo:link-availability* [availability] | +--rw bwatopo:availability decimal64 | +--rw bwatopo:link-bandwidth? uint64 +--ro bwatopo:actual-bandwidth? yang:gauge64 A.2. A JSON example { "ietf-network:networks": { "network": [ { "network-id": "Generic-network", "network-types": { "ietf-te-topology:te-topology": { "ietf-eth-te-topology:eth-tran-topology": {} } }, "node": [ { "node-id": "Generic-N1", "ietf-network-topology:termination-point": [ { "tp-id": "Generic-N1-TP1" } ] }, { "node-id": "Generic-N2", "ietf-network-topology:termination-point": [ { "tp-id": "Generic-N2-TP2" } ] } Ahlberg, et al. Expires 7 September 2023 [Page 10] Internet-Draft BWA Topo YANG Model March 2023 ], "ietf-network-topology:link": [ { "link-id": "Generic-N1-N2", "source": { "source-node": "Generic-N1", "source-tp": "Generic-N1-TP1" }, "destination": { "dest-node": "Generic-N2", "dest-tp": "Generic-N2-TP2" }, "ietf-te-topology:te": { "te-link-attributes": { "ietf-bandwidth-availability-topology:link-availability": [ { "availability": "0.999", "link-bandwidth": "20000000" } ] } } } ] } ] } } Acknowledgments This document was prepared using kramdown The authors would like to thank ... Authors' Addresses Jonas Ahlberg Ericsson Email: jonas.ahlberg@ericsson.com Scott Mansfield Ericsson Email: scott.mansfield@ericsson.com Ahlberg, et al. Expires 7 September 2023 [Page 11] Internet-Draft BWA Topo YANG Model March 2023 Min Ye Huawei Technologies Email: amy.yemin@huawei.com Italo Busi Huawei Technologies Email: italo.busi@huawei.com Xi Li NEC Laboratories Europe Email: xi.li@neclab.eu Daniela Spreafico Nokia - IT Email: daniela.spreafico@nokia.com Ahlberg, et al. Expires 7 September 2023 [Page 12]