MPLS Working Group T. Saad Internet-Draft V. Beeram Intended status: Standards Track Juniper Networks Expires: May 6, 2021 November 2, 2020 YANG Data Model for Network Slice Per-Hop Definition draft-bestbar-teas-yang-ns-phd-00 Abstract This document defines a YANG data model for the management of Network Slice Per-Hop Definitions (Slice-PHDs) on network slicing capable nodes in IP/MPLS networks. 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. 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 May 6, 2021. 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 Saad & Beeram Expires May 6, 2021 [Page 1] Internet-Draft NS PHD YANG Data Model November 2020 publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Tree Structure . . . . . . . . . . . . . . . . . . . . . 3 2. Network Slice Per-Hop Definition Model . . . . . . . . . . . 3 2.1. Model Usage . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Model Structure . . . . . . . . . . . . . . . . . . . . . 3 2.3. Network Slice Per-Hop-Behaviors . . . . . . . . . . . . . 4 2.4. Network Slices . . . . . . . . . . . . . . . . . . . . . 4 2.4.1. Slice Resource Reservation . . . . . . . . . . . . . 5 2.4.2. Slice Selectors . . . . . . . . . . . . . . . . . . . 5 2.4.3. Slice Per-Hop-Behavior . . . . . . . . . . . . . . . 6 2.4.4. Slice Membership . . . . . . . . . . . . . . . . . . 6 2.5. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 7 3. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 25 4. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 25 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25 6. Security Considerations . . . . . . . . . . . . . . . . . . . 26 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 27 7.1. Normative References . . . . . . . . . . . . . . . . . . 27 7.2. Informative References . . . . . . . . . . . . . . . . . 28 Appendix A. Complete Model Tree Structure . . . . . . . . . . . 28 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31 1. Introduction Network slicing in IP/MPLS networks can be realized by partitioning the shared network resources in just the control plane or in just the data plane or in both the control and data planes [I-D.bestbar-teas-ns-packet]. The latter two approaches require the forwarding engine on each network slicing capable node to identify the traffic belonging to a specific slice and to apply the corresponding Slice Per-Hop Behavior (Slice-PHB) that determines the forwarding treatment of the packets belonging to the network slice. The identification of the slice that the packet belongs to and the corresponding forwarding treatment that needs to be applied to the packet is dictated by the Network Slice Per-Hop Definition (Slice- PHD) that is provisioned on each network slicing capable node. Saad & Beeram Expires May 6, 2021 [Page 2] Internet-Draft NS PHD YANG Data Model November 2020 This document defines a YANG data model for the provisioning and management of Slice-PHDs on network slicing capable nodes in IP/MPLS networks. 1.1. Terminology The terminology for describing YANG data models is found in [RFC7950]. The reader is expected to be familiar with the terminology specified in [I-D.nsdt-teas-ietf-network-slice-definition], [I-D.nsdt-teas-ns-framework] and [I-D.bestbar-teas-ns-packet]. The term "Network Slice" used in this document must be interpreted as "IETF Network Slice" [I-D.nsdt-teas-ietf-network-slice-definition]. 1.2. Tree Structure A simplified graphical representation of the data model is presented in Appendix A of this document. The tree format defined in [RFC8340] is used for the YANG data model tree representation. 2. Network Slice Per-Hop Definition Model 2.1. Model Usage The instantiation of a network slice may require a network slice controller that accepts a service layer slice customer intent as input and translates it to a network-wide consistent per-hop slice definition that is distributed to network slicing capable nodes. The specification of the service layer slice customer intent is outside the scope of this document. The data model defined in this document covers the per-hop slice definition that is consumed by the network slicing capable nodes. 2.2. Model Structure The high-level model structure defined by this document is as shown below: Saad & Beeram Expires May 6, 2021 [Page 3] Internet-Draft NS PHD YANG Data Model November 2020 module: ietf-network-slice-phd +--rw network-slicing! +--rw network-slice-phbs | +--rw network-slice-phb* [id] | ............ +--rw network-slices +--rw network-slice* [name] | ............ +--rw slice-resource-reservation | ............ +--rw slice-selectors | +--rw slice-selector* [id] | ............ +--rw slice-phb? ns-phb-ref | ............ +--rw slice-membership ............ In addition to the set of Slice-PHDs (network-slices), the model also includes a placeholder for the set of Slice-PHBs (network-slice-phbs) that are referenced by the Slice-PHDs. 2.3. Network Slice Per-Hop-Behaviors The Slice-PHBs (network-slice-phbs) container carries a list of Slice-PHB (network-slice-phb) entries. Each of these entries can be referenced by one or more Slice-PHD. A Slice-PHB entry can either carry a reference to a generic PHB profile available on the node or carry a custom PHB profile. The custom PHB profile includes sufficient attributes to construct a slice specific Qos profile and any classes within it. +--rw network-slice-phbs | +--rw network-slice-phb* [id] | +--rw id uint16 | +--rw (profile-type)? | +--:(profile) | | +--rw profile? string | +--:(custom-profile) | ............ 2.4. Network Slices The Slice-PHDs are held in a container called 'network-slices'. Each network-slice entry is identified by a name and holds the set of per- hop attributes needed to instantiate the network slice. The four key elements of each network-slice entry are discussed in the following sub-sections. Saad & Beeram Expires May 6, 2021 [Page 4] Internet-Draft NS PHD YANG Data Model November 2020 2.4.1. Slice Resource Reservation The 'slice-resource-reservation' container carries data nodes that are used to support Slice-aware Bandwidth Engineering. The data nodes in this container facilitate preference-based preemption of Slice-aware TE paths, sharing of resources amongst a group of slices and backup slice path bandwidth protection. +--rw slice-resource-reservation | +--rw preference? uint16 | +--rw (max-bw-type)? | | +--:(bw-value) | | | +--rw maximum-bandwidth? uint64 | | +--:(bw-percentage) | | +--rw maximum-bandwidth-percent? | | rt-types:percentage | +--rw shared-resource-groups* uint32 | +--rw protection | +--rw backup-slice-id? uint32 | +--rw (backup-bw-type)? | +--:(backup-bw-value) | | +--rw backup-bandwidth? uint64 | +--:(backup-bw-percentage) | +--rw backup-bandwidth-percent? | rt-types:percentage 2.4.2. Slice Selectors The 'slice-selectors' container carries a set of data plane field selectors which are used to identify the packets belonging to the given network slice. Each slice selector is uniquely identified by a 16-bit ID. The slice selector with the lowest ID is the default slice selector used by all the topological elements that are members of the given network slice. The other entries may be used when there is a need to override the default slice selector on some select topological elements. Saad & Beeram Expires May 6, 2021 [Page 5] Internet-Draft NS PHD YANG Data Model November 2020 +--rw slice-selectors | +--rw slice-selector* [id] | +--rw id uint16 | +--rw mpls | | +--rw (ss-mpls-type)? | | +--:(label-value) | | | +--rw label? | | | | rt-types:mpls-label | | | +--rw label-position? identityref | | | +--rw label-position-offset? uint8 | | +--:(label-ranges) | | +--rw label-range* [index] | | +--rw index string | | +--rw start-label? | | | rt-types:mpls-label | | +--rw end-label? | | | rt-types:mpls-label | | +--rw label-position? | | | identityref | | +--rw label-position-offset? uint8 | +--rw ipv4 | | +--rw destination-prefix* inet:ipv4-prefix | +--rw ipv6 | | +--rw (ss-ipv6-type)? | | +--:(ipv6-destination) | | | +--rw destination-prefix* | | | inet:ipv6-prefix | | +--:(ipv6-flow-label) | | +--rw slid-flow-labels | | +--rw slid-flow-label* [slid] | | +--rw slid inet:ipv6-flow-label | | +--rw bitmask? uint32 | +--rw acl-ref* ns-acl-ref 2.4.3. Slice Per-Hop-Behavior The Slice-PHB leaf carries a reference to the appropriate PHB that needs to be applied for the given network slice. Unless specified otherwise, this is the default Slice-PHB to be used by all the topological elements that are members of the given network slice. +--rw slice-phb? ns-phb-ref 2.4.4. Slice Membership The 'slice-membership' container consists of a set of filtering policies that are used to determine which topological elements on the given node belong to the specific network slice. A filtering policy Saad & Beeram Expires May 6, 2021 [Page 6] Internet-Draft NS PHD YANG Data Model November 2020 could either reference a predefined topology or specify the rules to construct a customized topology using a set of include and exclude filters. The topological elements that satisfy the network slice membership criteria can optionally override the default Slice-PHB and/or the default slice selector. +--rw slice-membership +--rw filter-policies +--rw filter-policy* [id] +--rw id | uint16 +--rw (filter-type)? | +--:(topology-ref) | | +--rw (topo-ref-type)? | | +--:(algo-id) | | | +--rw algo-id? uint8 | | +--:(te-topo-id) | | +--rw te-topology-identifier | | +--rw provider-id? te-global-id | | +--rw client-id? te-global-id | | +--rw topology-id? | | te-topology-id | +--:(custom-topology) | +--rw include | | +--rw link-affinity* string | | +--rw link-name* string | | +--rw node-prefix* inet:ip-prefix | | +--rw as* inet:as-number | +--rw exclude | +--rw link-affinity* string | +--rw link-name* string | +--rw node-prefix* inet:ip-prefix | +--rw as* inet:as-number +--rw slice-selector? | ns-ss-ref +--rw slice-phb? ns-phb-ref 2.5. YANG Module file "ietf-network-slice-phd@2020-11-02" module ietf-network-slice-phd { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-network-slice-phd"; prefix "ns-phd"; import ietf-inet-types { prefix "inet"; Saad & Beeram Expires May 6, 2021 [Page 7] Internet-Draft NS PHD YANG Data Model November 2020 reference "RFC 6991: Common YANG Data Types"; } import ietf-routing-types { prefix "rt-types"; reference "RFC 8294: Common YANG Data Types for the Routing Area"; } import ietf-access-control-list { prefix "acl"; reference "RFC 8519: YANG Data Model for Network Access Control Lists (ACLs)"; } import ietf-te-types { prefix te-types; reference "RFC 8776: Common YANG Data Types for Traffic Engineering"; } organization "IETF Traffic Engineering Architecture and Signaling (TEAS) Working Group."; contact "WG Web: WG List: Editor: Vishnu Pavan Beeram Editor: Tarek Saad "; description "This YANG module defines a data model for managing Network Slice Per-Hop Definitions (Slice-PHDs) on a network slicing capable node. Copyright (c) 2020 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set Saad & Beeram Expires May 6, 2021 [Page 8] Internet-Draft NS PHD YANG Data Model November 2020 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 "2020-11-02" { description "Initial revision."; reference "RFC XXXX: YANG Data Model for Network Slice Per-Hop Definitions (Slice-PHDs)."; } /* * I D E N T I T I E S */ /* * Identity - MPLS Slice Selector Label Position Type */ identity ss-mpls-label-position-type { description "Base identity for the position of the MPLS label that is used for slice selection."; } identity ss-mpls-label-position-top { base ss-mpls-label-position-type; description "MPLS label that is used for slice selection is at the top of the label stack."; } identity ss-mpls-label-position-bottom { base ss-mpls-label-position-type; description "MPLS label that is used for slice selection is either at the bottom or at a specific offset from the bottom of the label stack."; } identity ss-mpls-label-position-indicator { base ss-mpls-label-position-type; description Saad & Beeram Expires May 6, 2021 [Page 9] Internet-Draft NS PHD YANG Data Model November 2020 "MPLS label that is used for slice selection is immediately preceded by a special purpose slice indicator label in the label stack."; } /* * Identity - Slice-PHB Class Direction */ identity s-phb-class-direction { description "Base identity for the direction of traffic to which the Slice PHB class profile is applied."; } identity s-phb-class-direction-in { base s-phb-class-direction; description "Slice PHB class profile is applied to incoming traffic."; } identity s-phb-class-direction-out { base s-phb-class-direction; description "Slice PHB class profile is applied to outgoing traffic."; } identity s-phb-class-direction-in-out { base s-phb-class-direction; description "Slice PHB class profile is applied to both incoming and outgoing directions of traffic."; } /* * Identity - Slice-PHB Class Priority */ identity s-phb-class-priority { description "Base identity for the priority of the child class scheduler."; } identity s-phb-class-priority-low { base s-phb-class-drop-probability; description "Priority of the child class scheduler is low."; } Saad & Beeram Expires May 6, 2021 [Page 10] Internet-Draft NS PHD YANG Data Model November 2020 identity s-phb-class-priority-strict-high { base s-phb-class-drop-probability; description "Priority of the child class scheduler is strict-high."; } /* * Identity - Slice-PHB Class Drop Probability */ identity s-phb-class-drop-probability { description "Base identity for the drop probability applied to packets exceeding the CIR of the class queue."; } identity s-phb-class-drop-probability-low { base s-phb-class-drop-probability; description "Low drop probability applied to packets exceeding the CIR of the class queue."; } identity s-phb-class-drop-probability-medium { base s-phb-class-drop-probability; description "Medium drop probability applied to packets exceeding the CIR of the class queue."; } identity s-phb-class-drop-probability-high { base s-phb-class-drop-probability; description "High drop probability applied to packets exceeding the CIR of the class queue."; } /* * T Y P E D E F S */ typedef ns-acl-ref { type leafref { path "/acl:acls/acl:acl/acl:name"; } description "This type is used to reference an ACL."; } Saad & Beeram Expires May 6, 2021 [Page 11] Internet-Draft NS PHD YANG Data Model November 2020 typedef ns-ss-ref { type leafref { path "/network-slicing/network-slices/network-slice/" + "slice-selectors/slice-selector/id"; } description "This type is used to reference a Slice Selector (SS)."; } typedef ns-phb-ref { type leafref { path "/network-slicing/network-slice-phbs/network-slice-phb/" + "id"; } description "This type is used to reference a Slice Per-Hop Behavior (Slice-PHB)."; } /* * G R O U P I N G S */ /* * Grouping - Slice Selector MPLS: Label location specific fields */ grouping ns-ss-mpls-label-location { description "Grouping for MPLS (SS) label location specific fields."; leaf label-position { type identityref { base ss-mpls-label-position-type; } description "MPLS label position - top, bottom with offset, Slice label indicator."; } leaf label-position-offset { when "derived-from-or-self(../label-position," + "'ns-phd:ss-mpls-label-position-bottom')" { description "MPLS label position offset is relevant only when the label-position is set to 'bottom'."; } type uint8; description "MPLS label position offset."; } Saad & Beeram Expires May 6, 2021 [Page 12] Internet-Draft NS PHD YANG Data Model November 2020 } /* * Grouping - Slice Selector (SS) */ grouping ns-slice-selector { description "Grouping for Slice Selectors."; container slice-selectors { description "Container for Slice Selectors."; list slice-selector { key "id"; description "List of Slice Selectors - this includes the default selector and others used for overriding the default."; leaf id { type uint16; description "A 16-bit ID to uniquely identify the Slice Selector. The Slice Selector with the lowest ID is the default selector."; } container mpls { description "Container for MPLS Slice Selector."; choice ss-mpls-type { description "Choices for MPLS Slice Selector."; case label-value { leaf label { type rt-types:mpls-label; description "MPLS Slice Selector Label is explicitly specified."; } uses ns-ss-mpls-label-location; } case label-ranges { list label-range { key "index"; unique "start-label end-label"; description "MPLS Slice Selector Label is picked from a specified set of label ranges."; leaf index { type string; description Saad & Beeram Expires May 6, 2021 [Page 13] Internet-Draft NS PHD YANG Data Model November 2020 "A string that uniquely identifies a label range."; } leaf start-label { type rt-types:mpls-label; must '. <= ../end-label' { error-message "The start-label must be less than or equal " + "to end-label"; } description "Label-range start."; } leaf end-label { type rt-types:mpls-label; must '. >= ../start-label' { error-message "The end-label must be greater than or equal " + "to start-label"; } description "Label-range end."; } uses ns-ss-mpls-label-location; } } } } container ipv4 { description "Container for IPv4 Slice Selector."; leaf-list destination-prefix { type inet:ipv4-prefix; description "IPv4 Slice Selector is picked from a specified set of IPv4 destination prefixes."; } } container ipv6 { description "Container for IPv6 Slice Selector."; choice ss-ipv6-type { description "Choices for IPv6 Slice Selector."; case ipv6-destination { leaf-list destination-prefix { type inet:ipv6-prefix; description Saad & Beeram Expires May 6, 2021 [Page 14] Internet-Draft NS PHD YANG Data Model November 2020 "IPv6 Slice Selector is picked from a specified set of IPv6 destination prefixes."; } } case ipv6-flow-label { container slid-flow-labels { description "Container for a set of Slice IDs that are encoded within the flow label."; list slid-flow-label { key "slid"; description "IPv6 Slice Selector is picked from a set of Slice IDs that are encoded within the flow label."; leaf slid { type inet:ipv6-flow-label; description "Slice ID encoded inside the IPv6 flow label."; } leaf bitmask { type uint32; description "Bitmask to extract the encoded Slice ID from the IPv6 flow label."; } } } } } } leaf-list acl-ref { type ns-acl-ref; description "Slice Selection is done based on the specified list of ACLs."; } } } } /* * Grouping - Slice Resource Reservation */ grouping ns-slice-resource-reservation { description "Grouping for Slice Resource Reservation."; container slice-resource-reservation { Saad & Beeram Expires May 6, 2021 [Page 15] Internet-Draft NS PHD YANG Data Model November 2020 description "Container for Slice Resource Reservation."; leaf preference { type uint16; description "Slice control plane preference. A higher preference indicates a more favorable slice resource reservation than a lower preference."; } choice max-bw-type { description "Choice of maximum bandwidth specification."; case bw-value { leaf maximum-bandwidth { type uint64; description "The maximum bandwidth allocated to a network slice on the network resources - specified as absolute value."; } } case bw-percentage { leaf maximum-bandwidth-percent { type rt-types:percentage; description "The maximum bandwidth allocated to a network slice on the network resources - specified as percentage of link capacity."; } } } leaf-list shared-resource-groups { type uint32; description "List of shared resource groups that a network slice shares its allocated resources with."; } container protection { description "Container for network slice protection reservation."; leaf backup-slice-id { type uint32; description "The Slice ID that identifies the network slice used for backup paths that protect primary paths in a specific network slice."; } choice backup-bw-type { description Saad & Beeram Expires May 6, 2021 [Page 16] Internet-Draft NS PHD YANG Data Model November 2020 "Choice of backup bandwidth specification."; case backup-bw-value { leaf backup-bandwidth { type uint64; description "The maximum bandwidth on a network resource that is allocated for backup traffic - specified as absolute value."; } } case backup-bw-percentage { leaf backup-bandwidth-percent { type rt-types:percentage; description "The maximum bandwidth on a network resource that is allocated for backup traffic - specified as percentage of the link capacity."; } } } } } } /* * Grouping - Slice-PHB */ grouping ns-slice-phb { description "Grouping for Slice-PHB."; leaf slice-phb { type ns-phb-ref; description "Reference to a specific Slice-PHB from the list global Slice-PHBs."; } } /* * Grouping - Slice default profile override */ grouping ns-slice-default-profile-override { description "Grouping of fields that are used to override the default profile of the network slice."; leaf slice-selector { type ns-ss-ref; description Saad & Beeram Expires May 6, 2021 [Page 17] Internet-Draft NS PHD YANG Data Model November 2020 "Reference to a specific Slice Selector."; } uses ns-slice-phb; } /* * Grouping - Slice membership filter: Topology reference */ grouping ns-slice-membership-topo-ref { description "Grouping for topology reference slice membership filter."; choice topo-ref-type { description "Choice of topology reference."; case algo-id { leaf algo-id { type uint8; description "Algorithm ID."; } } case te-topo-id { uses te-types:te-topology-identifier; } } } /* * Grouping - Slice membership filters: Custom topology */ grouping ns-slice-membership-custom-topo { description "Grouping for custom topology slice membership filters."; leaf-list link-affinity { type string; description "Match-filter is a list of link affinities."; } leaf-list link-name { type string; description "Match-filter is a list of link names."; } leaf-list node-prefix { type inet:ip-prefix; description "Match-filter is a list of node IDs."; } Saad & Beeram Expires May 6, 2021 [Page 18] Internet-Draft NS PHD YANG Data Model November 2020 leaf-list as { type inet:as-number; description "Match-filter is a list of AS numbers."; } } /* * Grouping - Slice membership filters */ grouping ns-slice-membership-filters { description "Grouping for Slice Membership filters."; choice filter-type { description "Choice of filter type."; case topology-ref { uses ns-slice-membership-topo-ref; } case custom-topology { container include { description "Include policies."; uses ns-slice-membership-custom-topo; } container exclude { description "Exclude policies."; uses ns-slice-membership-custom-topo; } } } } /* * Grouping - Slice Membership */ grouping ns-slice-membership { description "Grouping for 'Slice Membership'."; container slice-membership { description "Container for Slice Membership."; container filter-policies { description "Container for topology filtering policies."; list filter-policy { key "id"; Saad & Beeram Expires May 6, 2021 [Page 19] Internet-Draft NS PHD YANG Data Model November 2020 description "List of topology filtering policies."; leaf id { type uint16; description "A 16-bit ID that uniquely identifies the topology filtering policy."; } uses ns-slice-membership-filters; uses ns-slice-default-profile-override; } } } } /* * Grouping - Network Slice Per-Hop Behaviors (Slice-PHBs) */ grouping ns-phbs { description "Grouping for Slice-PHBs."; container network-slice-phbs { description "Container for Slice-PHBs."; list network-slice-phb { key "id"; description "List of Slice-PHBs."; leaf id { type uint16; description "A 16-bit ID that uniquely identifies the Slice-PHB."; } choice profile-type { description "Choice of PHB profile type."; case profile { description "Generic PHB profile available on the network element."; leaf profile { type string; description "Generic PHB profile identifier."; } } case custom-profile { description Saad & Beeram Expires May 6, 2021 [Page 20] Internet-Draft NS PHD YANG Data Model November 2020 "Custom PHB profile."; choice guaranteed-rate-type { description "Guaranteed rate is the committed information rate (CIR) of the Slice. The guaranteed rate also determines the amount of excess (extra) bandwidth that a group of Slices can share. Extra bandwidth is allocated among the group in proportion to the guaranteed rate of each Slice."; case rate { leaf guaranteed-rate { type uint64; description "Guaranteed rate specified as absolute value."; } } case percentage { leaf guaranteed-rate-percent { type rt-types:percentage; description "Guaranteed rate specified in percentage."; } } } choice shaping-rate-type { description "Shaping rate is the maximum bandwidth of the slice, or the peak information rate (PIR) of a Slice."; case rate { leaf shaping-rate { type uint64; description "Shaping rate specified as absolute value."; } } case percentage { leaf shaping-rate-percent { type rt-types:percentage; description "Shaping rate specified in percentage."; } } } container classes { description "Container for classes."; list class { key class-id; Saad & Beeram Expires May 6, 2021 [Page 21] Internet-Draft NS PHD YANG Data Model November 2020 description "List of classes."; leaf class-id { type string; description "A string to uniquely identify a class."; } leaf direction { type identityref { base s-phb-class-direction; } description "Class direction."; } leaf priority { type identityref { base s-phb-class-priority; } description "Priority of the class scheduler. Only one Slice class queue can be set as a strict-high priority queue. Strict-high priority allocates the scheduled bandwidth to the queue before any other queue receives bandwidth. Other queues receive the bandwidth that remains after the strict-high queue has been serviced."; } choice guaranteed-rate-type { description "Guaranteed Rate is the Committed information rate (CIR) of Slice class - specified as absolute value or percentage."; case rate { leaf guaranteed-rate { type uint64; description "Guaranteed rate specified as absolute value."; } } case percentage { leaf guaranteed-rate-percent { type rt-types:percentage; description "Guaranteed rate specified in percentage."; } } } Saad & Beeram Expires May 6, 2021 [Page 22] Internet-Draft NS PHD YANG Data Model November 2020 leaf drop-probability { type identityref { base s-phb-class-drop-probability; } description "Drop probability applied to packets exceeding the CIR of the class queue."; } choice maximum-bandwidth-type { description "Maximum bandwidth is the Peak information rate (PIR) of Slice class - specified as absolute value or percentage."; case rate { leaf maximum-bandwidth { type uint64; description "Maximum bandwidth specified as absolute value."; } } case percentage { leaf maximum-bandwidth-percent { type rt-types:percentage; description "Maximum bandwidth specified as percentage."; } } } choice delay-buffer-size-type { description "Size of the queue buffer as a percentage of the dedicated buffer space - specified as value or percentage."; case value { leaf delay-buffer-size { type uint64; description "Delay buffer size."; } } case percentage { leaf delay-buffer-size-percent { type rt-types:percentage; description "Delay buffer size specified as percentage."; } } Saad & Beeram Expires May 6, 2021 [Page 23] Internet-Draft NS PHD YANG Data Model November 2020 } } } } } } } } /* * Grouping - Network Slice Per-Hop Definitions (Slice-PHDs) */ grouping ns-entries { description "Grouping for Slice-PHDs."; container network-slices { description "Container for Slice-PHD entries (network-slices)."; list network-slice { key "name"; unique "id"; description "List of network slices."; leaf name { type string; description "A string that uniquely identifies the network slice."; } leaf id { type uint32; description "A 32-bit ID that uniquely identifies the network slice."; } uses ns-slice-resource-reservation; uses ns-slice-selector; uses ns-slice-phb; uses ns-slice-membership; } } } /* * Top-level container - Network Slicing */ container network-slicing { presence "Enable network slicing."; description Saad & Beeram Expires May 6, 2021 [Page 24] Internet-Draft NS PHD YANG Data Model November 2020 "Top-level container for network slicing specific constructs on a network slicing capable node."; uses ns-phbs; uses ns-entries; } } 3. Acknowledgements The authors would like to thank Krzysztof Szarkowicz for his input from discussions. 4. Contributors The following individuals contributed to this document: Colby Barth Juniper Networks Email: cbarth@juniper.net Srihari R. Sangli Juniper Networks Email: ssangli@juniper.net Chandra Ramachandran Juniper Networks Email: csekar@juniper.net 5. IANA Considerations This document registers the following URI in the IETF XML registry [RFC3688]. Following the format in [RFC3688], the following registration is requested to be made. URI: urn:ietf:params:xml:ns:yang:ietf-network-slice-phd Registrant Contact: The TEAS WG of the IETF. XML: N/A, the requested URI is an XML namespace. This document registers a YANG module in the YANG Module Names registry [RFC6020]. name: ietf-network-slice-phd namespace: urn:ietf:params:xml:ns:yang:ietf-network-slice-phd prefix: ns-phd reference: RFCXXXX Saad & Beeram Expires May 6, 2021 [Page 25] Internet-Draft NS PHD YANG Data Model November 2020 6. 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 Network 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. The data nodes defined in this YANG module that are writable/creatable/deletable (i.e., config true, which is the default) 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 subtrees and data nodes and their sensitivity/vulnerability: * "/network-slicing/network-slice-phbs": This subtree specifies the configurations for network slice per-hop behaviors. By manipulating these data nodes, a malicious attacker may cause unauthorized and improper behavior to be provided for the slice traffic on the network element. * "/network-slicing/network-slices": This subtree specifies the configurations for network slices on a given network element. By manipulating these data nodes, a malicious attacker may cause unauthorized and improper behavior to be provided for the slice traffic on the network element. The readable data nodes in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability: * "/network-slicing/network-slice-phbs": Unauthorized access to this subtree can disclose the network slice PHBs defined on the network element. * "/network-slicing/network-slices": Unauthorized access to this subtree can disclose the network slice definitions on the network element. Saad & Beeram Expires May 6, 2021 [Page 26] Internet-Draft NS PHD YANG Data Model November 2020 7. References 7.1. Normative References [I-D.bestbar-teas-ns-packet] Saad, T. and V. Beeram, "Realizing Network Slices in IP/ MPLS Networks", draft-bestbar-teas-ns-packet-00 (work in progress), October 2020. [I-D.nsdt-teas-ietf-network-slice-definition] Rokui, R., Homma, S., Makhijani, K., Contreras, L., and J. Tantsura, "Definition of IETF Network Slices", draft-nsdt- teas-ietf-network-slice-definition-00 (work in progress), October 2020. [I-D.nsdt-teas-ns-framework] Gray, E. and J. Drake, "Framework for Transport Network Slices", draft-nsdt-teas-ns-framework-04 (work in progress), July 2020. [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, . [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . Saad & Beeram Expires May 6, 2021 [Page 27] Internet-Draft NS PHD YANG Data Model November 2020 [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, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 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 [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . Appendix A. Complete Model Tree Structure module: ietf-network-slice-phd +--rw network-slicing! +--rw network-slice-phbs | +--rw network-slice-phb* [id] | +--rw id uint16 | +--rw (profile-type)? | +--:(profile) | | +--rw profile? string | +--:(custom-profile) | +--rw (guaranteed-rate-type)? | | +--:(rate) | | | +--rw guaranteed-rate? uint64 | | +--:(percentage) | | +--rw guaranteed-rate-percent? | | rt-types:percentage | +--rw (shaping-rate-type)? | | +--:(rate) | | | +--rw shaping-rate? uint64 | | +--:(percentage) | | +--rw shaping-rate-percent? | | rt-types:percentage | +--rw classes | +--rw class* [class-id] Saad & Beeram Expires May 6, 2021 [Page 28] Internet-Draft NS PHD YANG Data Model November 2020 | +--rw class-id | | string | +--rw direction? | | identityref | +--rw priority? | | identityref | +--rw (guaranteed-rate-type)? | | +--:(rate) | | | +--rw guaranteed-rate? | | | uint64 | | +--:(percentage) | | +--rw guaranteed-rate-percent? | | rt-types:percentage | +--rw drop-probability? | | identityref | +--rw (maximum-bandwidth-type)? | | +--:(rate) | | | +--rw maximum-bandwidth? | | | uint64 | | +--:(percentage) | | +--rw maximum-bandwidth-percent? | | rt-types:percentage | +--rw (delay-buffer-size-type)? | +--:(value) | | +--rw delay-buffer-size? | | uint64 | +--:(percentage) | +--rw delay-buffer-size-percent? | rt-types:percentage +--rw network-slices +--rw network-slice* [name] +--rw name string +--rw id? uint32 +--rw slice-resource-reservation | +--rw preference? uint16 | +--rw (max-bw-type)? | | +--:(bw-value) | | | +--rw maximum-bandwidth? uint64 | | +--:(bw-percentage) | | +--rw maximum-bandwidth-percent? | | rt-types:percentage | +--rw shared-resource-groups* uint32 | +--rw protection | +--rw backup-slice-id? uint32 | +--rw (backup-bw-type)? | +--:(backup-bw-value) | | +--rw backup-bandwidth? uint64 | +--:(backup-bw-percentage) Saad & Beeram Expires May 6, 2021 [Page 29] Internet-Draft NS PHD YANG Data Model November 2020 | +--rw backup-bandwidth-percent? | rt-types:percentage +--rw slice-selectors | +--rw slice-selector* [id] | +--rw id uint16 | +--rw mpls | | +--rw (ss-mpls-type)? | | +--:(label-value) | | | +--rw label? | | | | rt-types:mpls-label | | | +--rw label-position? identityref | | | +--rw label-position-offset? uint8 | | +--:(label-ranges) | | +--rw label-range* [index] | | +--rw index string | | +--rw start-label? | | | rt-types:mpls-label | | +--rw end-label? | | | rt-types:mpls-label | | +--rw label-position? | | | identityref | | +--rw label-position-offset? uint8 | +--rw ipv4 | | +--rw destination-prefix* inet:ipv4-prefix | +--rw ipv6 | | +--rw (ss-ipv6-type)? | | +--:(ipv6-destination) | | | +--rw destination-prefix* | | | inet:ipv6-prefix | | +--:(ipv6-flow-label) | | +--rw slid-flow-labels | | +--rw slid-flow-label* [slid] | | +--rw slid inet:ipv6-flow-label | | +--rw bitmask? uint32 | +--rw acl-ref* ns-acl-ref +--rw slice-phb? ns-phb-ref +--rw slice-membership +--rw filter-policies +--rw filter-policy* [id] +--rw id | uint16 +--rw (filter-type)? | +--:(topology-ref) | | +--rw (topo-ref-type)? | | +--:(algo-id) | | | +--rw algo-id? uint8 | | +--:(te-topo-id) | | +--rw te-topology-identifier Saad & Beeram Expires May 6, 2021 [Page 30] Internet-Draft NS PHD YANG Data Model November 2020 | | +--rw provider-id? te-global-id | | +--rw client-id? te-global-id | | +--rw topology-id? | | te-topology-id | +--:(custom-topology) | +--rw include | | +--rw link-affinity* string | | +--rw link-name* string | | +--rw node-prefix* inet:ip-prefix | | +--rw as* inet:as-number | +--rw exclude | +--rw link-affinity* string | +--rw link-name* string | +--rw node-prefix* inet:ip-prefix | +--rw as* inet:as-number +--rw slice-selector? | ns-ss-ref +--rw slice-phb? ns-phb-ref Authors' Addresses Tarek Saad Juniper Networks Email: tsaad@juniper.net Vishnu Pavan Beeram Juniper Networks Email: vbeeram@juniper.net Saad & Beeram Expires May 6, 2021 [Page 31]