]> Orange

mohamed.boucadair@orange.com

Juniper

rroberts@juniper.net

Telefonica

oscar.gonzalezdedios@telefonica.com

Nokia

samier.barguil_giraldo@nokia.com

Huawei Technologies

lana.wubo@huawei.com

Operations and Management OPSAWG Slice Service L3VPN L2VPN The document specifies a common Attachment Circuits (ACs) YANG module, which is designed with the intent to be reusable by other models. For example, this common model can be reused by service models to expose ACs as a service, service models that require binding a service to a set of ACs, network and device models to provision ACs, etc. Discussion Venues Discussion of this document takes place on the Operations and Management Area Working Group Working Group mailing list (opsawg@ietf.org), which is archived at . Source for this draft and an issue tracker can be found at .

Introduction Connectivity services are provided by networks to customers via dedicated terminating points (e.g., service functions, customer edges (CEs), peer ASBRs, data centers gateways, Internet Exchange Points). A connectivity service is basically about ensuring data transfer received from (or destined to) a given terminating point to (or from) other terminating points that belong to the same customer/service, an interconnection node, or an ancillary node. A set of objectives for the connectivity service may eventually be negotiated and agreed upon between a customer a network provider. For that data transfer to take place within the provider network, it is assumed that adequate setup is provisioned over the links that connect customer terminating points and a provider network so that data can be successfully exchanged over these links. The required setup is referred to in this document as Attachment Circuits (ACs), while the underlying link is referred to as "bearers". This document adheres to the definition of an Attachment Circuit as provided in Section 1.2 of , especially:

• Routers can be attached to each other, or to end systems, in a variety of different ways: PPP connections, ATM Virtual Circuits (VCs), Frame Relay VCs, ethernet interfaces, Virtual Local Area Networks (VLANs) on ethernet interfaces, GRE tunnels, Layer 2 Tunneling Protocol (L2TP) tunnels, IPsec tunnels, etc. We will use the term "attachment circuit" to refer generally to some such means of attaching to a router. An attachment circuit may be the sort of connection that is usually thought of as a "data link", or it may be a tunnel of some sort; what matters is that it be possible for two devices to be network layer peers over the attachment circuit.

When a customer requests a new value-added service, the service can be bound to existing attachment circuits or trigger the instantiation of new attachment circuits. Whether these AC are specific to a given service or be used to deliver a variety of services is deployment specific. An example of ACs is depicted in . A Customer Terminating Point (CTP) may be a physical node or a logical entity. A CTP is seen by the network as a peer Service Attachment Point (SAP) . CTPs may be dedicated to one single service or host multiple services (e.g., service functions ). A single AC (as seen by a network provider) may be bound to one or multiple peer SAPs (e.g., CTP#1 and CTP#2). For example, and as discussed in , multiple CTPs (CEs) can be attached to a PE over the same attachment circuit. This is typically implemented if the layer 2 infrastructure between the CTP and the network provides a multipoint service. The same CTP may terminate multiple ACs. These ACes may be over the same or distinct bearers.

Examples of ACs

This document specifies a common module ("ietf-ac-common") for ACS. The model is designed with the intent to be reusable by other models and therefore ensure consistent AC structures among modules that manipulate ACs. For example, the common model can be reused by service models to expose AC as a service (e.g., ), service models that require binding a service to a set of ACs (e.g., )), network models to provision ACs (e.g., ), device models, etc. The YANG data models in this document conform to the Network Management Datastore Architecture (NMDA) defined in .

Conventions and Definitions 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 when, and only when, they appear in all capitals, as shown here. The meanings of the symbols in the YANG tree diagrams are defined in . This document uses the following terms:

Bearer:

A physical or logical link that connects a customer node (or site) to a provider network. A bearer can be a wireless or wired link. One or multiple technologies can be used to build a bearer. The bearer type can be specified by a customer.

The operator allocates a unique bearer reference to identify a bearer within its network (e.g., customer line identifier). Such a reference can be retrieved by a customer and used in subsequent service placement requests to unambiguously identify where a service is to be bound.

The concept of bearer can be generalized to refer to the required underlying connection for the provisioning of an attachment circuit. One or multiple attachment circuits may be hosted over the same bearer (e.g., multiple VLANs on the same bearer that is provided by a physical link).

Network controller:

Denotes a functional entity responsible for the management of the service provider network.

Service orchestrator:

Refers to a functional entity that interacts with the customer of a network service. The service orchestrator is typically responsible for the attachment circuits, the Provider Edge (PE) selection, and requesting the activation of the requested service to a network controller.

Service provider network:

A network that is able to provide network services (e.g., Layer 3 VPN, Layer 2 VPN, and Network Slice Services).

Service provider:

A service provider that offers network services (e.g., Layer 3 VPN, Layer 2 VPN, and Network Slice Services).

Description of the AC Common YANG Module The full tree of the "ietf-ac-common" module is shown in .

Identities The module defines a set of identities, including the following:

'address-allocation-type':

Used to specify the IP address allocation type in an AC.

'local-defined-next-hop':

Used to specify next hop actions. For example, this identity can be used to indicate an action to discard traffic for a given destination or treat traffic towards addresses within the specified next-hop prefix as though they are connected to a local link.

'l2-tunnel-type':

Uses to control the Layer 2 tunnel selection for an AC. The current version supports indicating pseudowire, Virtual Private LAN Service (VPLS), and Virtual eXtensible Local Area Network (VXLAN).

'precedence-type':

Used to redundancy type when requesting ACs. For example, this identity can be used to tag a primary AC and a secondary AC.

Reusable Groupings The module also defines a set of reusable groupings, including the following:

'op-instructions' ():

Defines a set of parameters to specify scheduling instructions and report related events for an AC.

Operational Instructions Grouping

Layer 2 encapsulations ():

Groupings for the following encapsulation schemes are supported: dot1Q, QinQ, and priority-tagged.

Layer 2 tunnel services ():

These grouping are used to define layer 2 tunnel services that may be needed for the activation of an AC. Examples of supported Layer 2 servers are the pseudowire (Section 6.1 of ), a Virtual Private LAN Service (VPLS), or a Virtual eXtensible Local Area Networks (VXLANs) .

Layer 2 Connection Groupings

Layer 3 address allocation ():

Defines both IPv4 and IPv6 groupings to specify IP address allocation over an AC.

IP connections ()::

Defines IPv4 and IPv6 grouping for managing layer 3 connectivity over an AC. Both basic and more elaborated IP connection groupings are supported.

Layer 3 Connection Groupings

Routing parameters ():

In addition to static routing, the module supports the following routing protocols: BGP , OSPF or , IS-IS , and RIP . For all supported routing protocols, 'address-family' indicates whether IPv4, IPv6, or both address families are to be activated. For example, this parameter is used to determine whether RIPv2 , RIP Next Generation (RIPng), or both are to be enabled . More details about supported routing groupings are provided hereafter:

• Authentication: These groupings include the required information to manage the authentication of OSPF, IS-IS, BGP, and RIP. Similar to , this version of the common AC model assumes that parameters specific to the TCP-AO are preconfigured as part of the key chain that is referenced in the model. No assumption is made about how such a key chain is preconfigured. However, the structure of the key chain should cover data nodes beyond those in , mainly SendID and RecvID (Section 3.1 of ).
• BGP peer groups: Includes a set of parameters to identify a BGP peer group. Such a group can be defined by providing a local AS Number (ASN), a customer's ASN, and the address families to be activated for this group. BGP peer groups can be identified by a name.
• Basic parameters: These groupings include the minimal set of routing configuration that is required for the activation of OSPF, IS-IS, BGP, and RIP.
• Static routing: Parameters to configure an entry of a list of IP static routing entries.

Layer 3 Connection Groupings

Common Attachment Circuit YANG Module This module uses types defined in , , and . WG List: Editor: Mohamed Boucadair Author: Richard Roberts Author: Oscar Gonzalez de Dios Author: Samier Barguil Author: Bo Wu "; description "This YANG module defines a YANG model common to attachment circuits. 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 xxx; see the RFC itself for full legal notices."; revision 2022-11-30 { description "Initial revision."; reference "RFC xxxx: A Common YANG Data Model for Attachment Circuits"; } /****************************Identities************************/ // IP address allocation types identity address-allocation-type { description "Base identity for address allocation type in the AC."; } identity provider-dhcp { base address-allocation-type; description "The provider's network provides a DHCP service to the customer."; } identity provider-dhcp-relay { base address-allocation-type; description "The provider's network provides a DHCP relay service to the customer."; } identity provider-dhcp-slaac { if-feature "vpn-common:ipv6"; base address-allocation-type; description "The provider's network provides a DHCP service to the customer as well as IPv6 Stateless Address Autoconfiguration (SLAAC)."; reference "RFC 4862: IPv6 Stateless Address Autoconfiguration"; } identity static-address { base address-allocation-type; description "The provider's network provides static IP addressing to the customer."; } identity slaac { if-feature "vpn-common:ipv6"; base address-allocation-type; description "The provider's network uses IPv6 SLAAC to provide addressing to the customer."; reference "RFC 4862: IPv6 Stateless Address Autoconfiguration"; } identity dynamic-infra { base address-allocation-type; description "The IP address is dynamically allocated by the hosting infrastrcture."; } // next-hop actions identity local-defined-next-hop { description "Base identity of local defined next hops."; } identity discard { base local-defined-next-hop; description "Indicates an action to discard traffic for the corresponding destination. For example, this can be used to black-hole traffic."; } identity local-link { base local-defined-next-hop; description "Treat traffic towards addresses within the specified next-hop prefix as though they are connected to a local link."; } // Layer 2 tunnel types identity l2-tunnel-type { description "Base identity for Layer 2 tunnel selection for an AC."; } identity pseudowire { base l2-tunnel-type; description "Pseudowire tunnel termination for the AC."; } identity vpls { base l2-tunnel-type; description "Virtual Private LAN Service (VPLS) tunnel termination for the AC."; } identity vxlan { base l2-tunnel-type; description "Virtual eXtensible Local Area Network (VXLAN) tunnel termination for the AC."; } // Tagging precedence identity precedence-type { description "Redundancy type. The service can be created with primary and secondary tagging."; } identity primary { base precedence-type; description "Identifies the main attachment circuit."; } identity secondary { base precedence-type; description "Identifies the secondary attachment circuit."; } /****************************Typedefs************************/ typedef predefined-next-hop { type identityref { base local-defined-next-hop; } description "Predefined next-hop designation for locally generated routes."; } typedef area-address { type string { pattern '[0-9A-Fa-f]{2}(\.[0-9A-Fa-f]{4}){0,6}'; } description "This type defines the area address format."; } /************************Reusable groupings********************/ /**** Operational instructions ****/ grouping op-instructions { description "Scheduling instructions."; leaf requested-start { type yang:date-and-time; description "Indicates the requested date and time when the service is expected to be active."; } leaf requested-stop { type yang:date-and-time; description "Indicates the requested date and time when the service is expected to be disabled."; } leaf actual-start { type yang:date-and-time; config false; description "Indciates the actual date and time when the service actually was enabled."; } leaf actual-stop { type yang:date-and-time; config false; description "Indciates the actual date and time when the service actually was disabled."; } } /**** Layer 2 encapsulations ****/ // Dot1q grouping dot1q { description "Defines a grouping for tagged interfaces."; leaf tag-type { type identityref { base vpn-common:tag-type; } description "Tag type."; } leaf cvlan-id { type uint16 { range "1..4094"; } description "VLAN identifier."; } } // priority-tagged grouping priority-tagged { description "Priority tagged."; leaf tag-type { type identityref { base vpn-common:tag-type; } description "Tag type."; } } // QinQ grouping qinq { description "Includes QinQ parameters."; leaf tag-type { type identityref { base vpn-common:tag-type; } description "Tag type."; } leaf svlan-id { type uint16; mandatory true; description "Service VLAN (S-VLAN) identifier."; } leaf cvlan-id { type uint16; mandatory true; description "Customer VLAN (C-VLAN) identifier."; } } /**** Layer 2 tunnel services ****/ // pseudowire (PW) grouping pseudowire { description "Includes pseudowire termination parameters."; leaf vcid { type uint32; description "Indicates a PW or virtual circuit (VC) identifier."; } leaf far-end { type union { type uint32; type inet:ip-address; } description "Neighbor reference."; reference "RFC 8077: Pseudowire Setup and Maintenance Using the Label Distribution Protocol (LDP), Section 6.1"; } } // VPLS grouping vpls { description "VPLS termination parameters."; leaf vcid { type uint32; description "VC identifier."; } leaf-list far-end { type union { type uint32; type inet:ip-address; } description "Neighbor reference."; } } // VXLAN grouping vxlan { description "VXLAN termination parameters."; leaf vni-id { type uint32; mandatory true; description "VXLAN Network Identifier (VNI)."; } leaf peer-mode { type identityref { base vpn-common:vxlan-peer-mode; } description "Specifies the VXLAN access mode. By default, the peer mode is set to 'static-mode'."; } leaf-list peer-ip-address { type inet:ip-address; description "List of a peer's IP addresses."; } } // Layer 2 Tunnel service grouping l2-tunnel-service { description "Defines a Layer 2 tunnel termination."; leaf type { type identityref { base l2-tunnel-type; } description "Selects the tunnel termination type for an AC."; } container pseudowire { when "derived-from-or-self(../type, 'pseudowire')" { description "Only applies when the Layer 2 service type is 'pseudowire'."; } description "Includes pseudowire termination parameters."; uses pseudowire; } container vpls { when "derived-from-or-self(../type, 'vpls')" { description "Only applies when the Layer 2 service type is 'vpls'."; } description "VPLS termination parameters."; uses vpls; } container vxlan { when "derived-from-or-self(../type, 'vxlan')" { description "Only applies when the Layer 2 service type is 'vxlan'."; } description "VXLAN termination parameters."; uses vxlan; } } /**** Layer 3 connection *****/ // IPv4 allocation type grouping ipv4-allocation-type { description "IPv4-specific parameters."; leaf prefix-length { type uint8 { range "0..32"; } description "Subnet prefix length expressed in bits. It is applied to both local and customer addresses."; } leaf address-allocation-type { type identityref { base address-allocation-type; } must "not(derived-from-or-self(current(), 'slaac') or " + "derived-from-or-self(current(), " + "'provider-dhcp-slaac'))" { error-message "SLAAC is only applicable to IPv6."; } description "Defines how IPv4 addresses are allocated to the peer site."; } } // IPv6 allocation type grouping ipv6-allocation-type { description "IPv6-specific parameters."; leaf prefix-length { type uint8 { range "0..128"; } description "Subnet prefix length expressed in bits. It is applied to both local and customer addresses."; } leaf address-allocation-type { type identityref { base address-allocation-type; } description "Defines how IPv6 addresses are allocated to the peer site."; } } // Basic parameters for IPv4 connection grouping ipv4-connection-basic { description "Basic set fof IPv4-specific parameters for the connection."; uses ipv4-allocation-type; choice allocation-type { description "Choice of the IPv4 address allocation."; case dynamic { description "When the addresses are allocated by DHCP or other dynamic means local to the infrastructure."; choice provider-dhcp { description "Parameters related to DHCP-allocated addresses. IP addresses are allocated by DHCP, that is provided by the operator."; leaf dhcp-service-type { type enumeration { enum server { description "Local DHCP server."; } enum relay { description "Local DHCP relay. DHCP requests are relayed to a provider's server."; } } description "Indicates the type of DHCP service to be enabled on an AC."; } } choice dhcp-relay { description "The DHCP relay is provided by the operator."; container customer-dhcp-servers { description "Container for a list of the customer's DHCP servers."; leaf-list server-ip-address { type inet:ipv4-address; description "IPv4 addresses of the customer's DHCP server."; } } } } } } // Basic parameters for IPv6 connection grouping ipv6-connection-basic { description "Basic set fof IPv6-specific parameters for the connection."; uses ipv6-allocation-type; choice allocation-type { description "Choice of the IPv6 address allocation."; case dynamic { description "When the addresses are allocated by DHCP or other dynamic means local to the infrastructure."; choice provider-dhcp { description "Parameters related to DHCP-allocated addresses. IP addresses are allocated by DHCP, that is provided by the operator."; leaf dhcp-service-type { type enumeration { enum server { description "Local DHCP server."; } enum relay { description "Local DHCP relay. DHCP requests are relayed to a provider's server."; } } description "Indicates the type of DHCP service to be enabled on the AC."; } } choice dhcp-relay { description "The DHCP relay is provided by the operator."; container customer-dhcp-servers { description "Container for a list of the customer's DHCP servers."; leaf-list server-ip-address { type inet:ipv6-address; description "IPv6 addresses of the customer's DHCP server."; } } } } } } // Full parameters for the IPv4 connection grouping ipv4-connection { description "IPv4-specific parameters."; leaf local-address { type inet:ipv4-address; description "The IP address used at the provider's interface."; } leaf virtual-address { type inet:ipv4-address; description "This addresss may be used for redundancy purposes."; } uses ipv4-allocation-type; choice allocation-type { description "Choice of the IPv4 address allocation."; case dynamic { description "When the addresses are allocated by DHCP or other dynamic means local to the infrastructure."; choice address-assign { default "number"; description "A choice for how IPv4 addresses are assigned."; case number { leaf number-of-dynamic-address { type uint16; description "Specifies the number of IP addresses to be assigned to the customer on the AC."; } } case explicit { container customer-addresses { description "Container for customer addresses to be allocated using DHCP."; list address-pool { key "pool-id"; description "Describes IP addresses to be dyncamically allocated. When only 'start-address' is present, it represents a single address. When both 'start-address' and 'end-address' are specified, it implies a range inclusive of both addresses."; leaf pool-id { type string; description "A pool identifier for the address range from 'start-address' to 'end-address'."; } leaf start-address { type inet:ipv4-address; mandatory true; description "Indicates the first address in the pool."; } leaf end-address { type inet:ipv4-address; description "Indicates the last address in the pool."; } } } } } choice provider-dhcp { description "Parameters related to DHCP-allocated addresses. IP addresses are allocated by DHCP, which is provided by the operator."; leaf dhcp-service-type { type enumeration { enum server { description "Local DHCP server."; } enum relay { description "Local DHCP relay. DHCP requests are relayed to a provider's server."; } } description "Indicates the type of DHCP service to be enabled on this AC."; } } choice dhcp-relay { description "The DHCP relay is provided by the operator."; container customer-dhcp-servers { description "Container for a list of the customer's DHCP servers."; leaf-list server-ip-address { type inet:ipv4-address; description "IPv4 addresses of the customer's DHCP server."; } } } } case static-addresses { description "Lists the IPv4 addresses that are used."; list address { key "address-id"; ordered-by user; description "Lists the IPv4 addresses that are used. The first address of the list is the primary address of the connection."; leaf address-id { type string; description "An identifier of the static IPv4 address."; } leaf customer-address { type inet:ipv4-address; description "An IPv4 address of the customer side."; } } } } } // Full parameters for the IPv6 connection grouping ipv6-connection { description "IPv6-specific parameters."; leaf local-address { type inet:ipv6-address; description "IPv6 address of the provider side."; } leaf virtual-address { type inet:ipv6-address; description "This addresss may be used for redundancy purposes."; } uses ipv6-allocation-type; choice allocation-type { description "Choice of the IPv6 address allocation."; case dynamic { description "When the addresses are allocated by DHCP or other dynamic means local to the infrastructure."; choice address-assign { default "number"; description "A choice for how IPv6 addresses are assigned."; case number { leaf number-of-dynamic-address { type uint16; description "Specifies the number of IP addresses to be assigned to the customer on this access."; } } case explicit { container customer-addresses { description "Container for customer addresses to be allocated using DHCP."; list address-pool { key "pool-id"; description "Describes IP addresses to be dyncamically allocated. When only 'start-address' is present, it represents a single address. When both 'start-address' and 'end-address' are specified, it implies a range inclusive of both addresses."; leaf pool-id { type string; description "A pool identifier for the address range from 'start-address' to 'end-address'."; } leaf start-address { type inet:ipv6-address; mandatory true; description "Indicates the first address in the pool."; } leaf end-address { type inet:ipv6-address; description "Indicates the last address in the pool."; } } } } } choice provider-dhcp { description "Parameters related to DHCP-allocated addresses. IP addresses are allocated by DHCP, which is provided by the operator."; leaf dhcp-service-type { type enumeration { enum server { description "Local DHCP server."; } enum relay { description "Local DHCP relay. DHCP requests are relayed to a provider's server."; } } description "Indicates the type of DHCP service to be enabled on this access."; } } choice dhcp-relay { description "The DHCP relay is provided by the operator."; container customer-dhcp-servers { description "Container for a list of the customer's DHCP servers."; leaf-list server-ip-address { type inet:ipv6-address; description "IPv6 addresses of the customer's DHCP server."; } } } } case static-addresses { description "Lists the IPv6 addresses that are used."; list address { key "address-id"; ordered-by user; description "Lists the IPv6 addresses that are used. The first address of the list is the primary IP address of the connection."; leaf address-id { type string; description "An identifier of the static IPv6 address."; } leaf customer-address { type inet:ipv6-address; description "An IPv6 address of the customer side."; } } } } } /**** Routing ****/ // Routing authentication grouping bgp-authentication { description "Grouping for BGP authentication parameters."; container authentication { description "Container for BGP authentication parameters."; leaf enable { type boolean; default "false"; description "Enables or disables authentication."; } container keying-material { when "../enable = 'true'"; description "Container for describing how a BGP routing session is to be secured on an AC."; choice option { description "Choice of authentication options."; case ao { description "Uses the TCP Authentication Option (TCP-AO)."; reference "RFC 5925: The TCP Authentication Option"; leaf enable-ao { type boolean; description "Enables the TCP-AO."; } leaf ao-keychain { type key-chain:key-chain-ref; description "Reference to the TCP-AO key chain."; reference "RFC 8177: YANG Data Model for Key Chains"; } } case md5 { description "Uses MD5 to secure the session."; reference "RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs), Section 13.2"; leaf md5-keychain { type key-chain:key-chain-ref; description "Reference to the MD5 key chain."; reference "RFC 8177: YANG Data Model for Key Chains"; } } case explicit { leaf key-id { type uint32; description "Key identifier."; } leaf key { type string; description "BGP authentication key. This model only supports the subset of keys that are representable as ASCII strings."; } leaf crypto-algorithm { type identityref { base key-chain:crypto-algorithm; } description "Indicates the cryptographic algorithm associated with the key."; } } } } } } grouping ospf-authentication { description "Authentication configuration."; container authentication { description "Container for OSPF authentication parameters."; leaf enable { type boolean; default "false"; description "Enables or disables authentication."; } container keying-material { when "../enable = 'true'"; description "Container for describing how an OSPF session is to be secured for this AC."; choice option { description "Options for OSPF authentication."; case auth-key-chain { leaf key-chain { type key-chain:key-chain-ref; description "Name of the key chain."; } } case auth-key-explicit { leaf key-id { type uint32; description "Key identifier."; } leaf key { type string; description "OSPF authentication key. This model only supports the subset of keys that are representable as ASCII strings."; } leaf crypto-algorithm { type identityref { base key-chain:crypto-algorithm; } description "Indicates the cryptographic algorithm associated with the key."; } } } } } } grouping isis-authentication { description "IS-IS authentication configuration."; container authentication { description "Container for IS-IS authentication parameters."; leaf enable { type boolean; default "false"; description "Enables or disables authentication."; } container keying-material { when "../enable = 'true'"; description "Container for describing how an IS-IS session is secured over an AC."; choice option { description "Options for IS-IS authentication."; case auth-key-chain { leaf key-chain { type key-chain:key-chain-ref; description "Name of the key chain."; } } case auth-key-explicit { leaf key-id { type uint32; description "Key identifier."; } leaf key { type string; description "IS-IS authentication key. This model only supports the subset of keys that are representable as ASCII strings."; } leaf crypto-algorithm { type identityref { base key-chain:crypto-algorithm; } description "Indicates the cryptographic algorithm associated with the key."; } } } } } } grouping rip-authentication { description "RIP authentication configuration."; container authentication { description "Container for RIP authentication parameters."; leaf enable { type boolean; default "false"; description "Enables or disables authentication."; } container keying-material { when "../enable = 'true'"; description "Container for describing how a RIP session is to be secured on this AC."; choice option { description "Specifies the authentication scheme."; case auth-key-chain { leaf key-chain { type key-chain:key-chain-ref; description "Name of the key chain."; } } case auth-key-explicit { leaf key { type string; description "RIP authentication key. This model only supports the subset of keys that are representable as ASCII strings."; } leaf crypto-algorithm { type identityref { base key-chain:crypto-algorithm; } description "Indicates the cryptographic algorithm associated with the key."; } } } } } } // Basic routing parameters grouping bgp-peer-group-without-name { description "Identifies a BGP peer-group configured on the local system."; leaf local-as { type inet:as-number; config false; description "Indicates a local AS Number (ASN). This ASN is exposed to a customer so that it knows which ASN to use to set up a BGP session."; } leaf peer-as { type inet:as-number; description "Indicates the customer's ASN when the customer requests BGP routing."; } leaf address-family { type identityref { base vpn-common:address-family; } description "This node contains the address families to be activated. 'dual-stack' means that both IPv4 and IPv6 will be activated."; } } grouping bgp-peer-group-with-name { description "Identifies a BGP peer-group configured on the local system - identified by a peer-group name"; leaf name { type string; description "Name of the BGP peer-group"; } uses bgp-peer-group-without-name; } grouping ospf-basic { description "Configuration specific to OSPF."; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates whether IPv4, IPv6, or both are to be activated."; } leaf area-id { type yang:dotted-quad; mandatory true; description "Area ID."; reference "RFC 4577: OSPF as the Provider/Customer Edge Protocol for BGP/MPLS IP Virtual Private Networks (VPNs), Section 4.2.3 RFC 6565: OSPFv3 as a Provider Edge to Customer Edge (PE-CE) Routing Protocol, Section 4.2"; } leaf metric { type uint16; default "1"; description "Metric of the AC. It is used in the routing state calculation and path selection."; } } grouping isis-basic { description "Basic configuration specific to IS-IS."; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates whether IPv4, IPv6, or both are to be activated."; } leaf area-address { type area-address; mandatory true; description "Area address."; } } // Static routing grouping ipv4-static-rtg-entry { description "Paramters to configure a specific IPv4 static routing entry."; leaf lan { type inet:ipv4-prefix; description "LAN prefixes."; } leaf lan-tag { type string; description "Internal tag to be used in service policies."; } leaf next-hop { type union { type inet:ip-address; type predefined-next-hop; } description "The next hop that is to be used for the static route. This may be specified as an IP address or a predefined next-hop type (e.g., 'discard' or 'local-link')."; } leaf metric { type uint32; description "Indicates the metric associated with the static route."; } } grouping ipv4-static-rtg { description "Configuration specific to IPv4 static routing."; list ipv4-lan-prefixes { if-feature "vpn-common:ipv4"; key "lan next-hop"; description "List of LAN prefixes for the site."; uses ipv4-static-rtg-entry; uses vpn-common:service-status; } } grouping ipv6-static-rtg-entry { description "Paramters to configure a specific IPv6 static routing entry."; leaf lan { type inet:ipv6-prefix; description "LAN prefixes."; } leaf lan-tag { type string; description "Internal tag to be used in service (e.g., VPN) policies."; } leaf next-hop { type union { type inet:ip-address; type predefined-next-hop; } description "The next hop that is to be used for the static route. This may be specified as an IP address or a predefined next-hop type (e.g., 'discard' or 'local-link')."; } leaf metric { type uint32; description "Indicates the metric associated with the static route."; } } grouping ipv6-static-rtg { description "Configuration specific to IPv6 static routing."; list ipv6-lan-prefixes { if-feature "vpn-common:ipv6"; key "lan next-hop"; description "List of LAN prefixes for the site."; uses ipv6-static-rtg-entry; uses vpn-common:service-status; } } // OAM: maintain or remove? grouping bfd { description "Container for BFD."; leaf holdtime { type uint32; units "milliseconds"; description "Expected BFD holdtime. The customer may impose some fixed values for the holdtime period if the provider allows the customer to use this function. If the provider doesn't allow the customer to use this function, fixed values will not be set."; reference "RFC 5880: Bidirectional Forwarding Detection (BFD), Section 6.8.18"; } } } ]]>

Security Considerations The YANG module specified in this document defines schema for data that is designed to be accessed via network management protocols such as NETCONF or RESTCONF . The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) . The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS . The Network Configuration Access Control Model (NACM) 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 "ietf-ac-common" module defines a set of identities, types, and groupings. These nodes are intended to be reused by other YANG modules. The module by itself does not expose any data nodes that are writable, data nodes that contain read-only state, or RPCs. YANG modules that use the groupings that are defined in this document should identify the corresponding security considerations. For example, reusing some of these groupings will expose privacy-related information (e.g., 'ipv6-lan-prefixes' or 'ipv4-lan-prefixes'). Disclosing such information may be considered a violation of the customer-provider trust relationship. Several groupings ('bgp-authentication', 'ospf-authentication', 'isis-authentication', and 'rip-authentication') rely upon for authentication purposes. As such, modules that will reuse these grouping will inherit the security considerations discussed in Section 5 of . Also, these groupings support supplying explicit keys as strings in ASCII format. The use of keys in hexadecimal string format would afford greater key entropy with the same number of key- string octets. However, such a format is not included in this version of the common AC model, because it is not supported by the underlying device modules (e.g., ).

IANA Considerations IANA is requested to register the following URI in the "ns" subregistry within the "IETF XML Registry" : IANA is requested to register the following YANG module in the "YANG Module Names" subregistry within the "YANG Parameters" registry.

References Normative References ISO Datastores are a fundamental concept binding the data models written in the YANG data modeling language to network management protocols such as the Network Configuration Protocol (NETCONF) and RESTCONF. This document defines an architectural framework for datastores based on the experience gained with the initial simpler model, addressing requirements that were not well supported in the initial model. This document updates RFC 7950. In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. Layer 2 services (such as Frame Relay, Asynchronous Transfer Mode, and Ethernet) can be emulated over an MPLS backbone by encapsulating the Layer 2 Protocol Data Units (PDUs) and then transmitting them over pseudowires (PWs). It is also possible to use pseudowires to provide low-rate Time-Division Multiplexed and Synchronous Optical NETworking circuit emulation over an MPLS-enabled network. This document specifies a protocol for establishing and maintaining the pseudowires, using extensions to the Label Distribution Protocol (LDP). Procedures for encapsulating Layer 2 PDUs are specified in other documents. This document is a rewrite of RFC 4447 for publication as an Internet Standard. This document describes Virtual eXtensible Local Area Network (VXLAN), which is used to address the need for overlay networks within virtualized data centers accommodating multiple tenants. The scheme and the related protocols can be used in networks for cloud service providers and enterprise data centers. This memo documents the deployed VXLAN protocol for the benefit of the Internet community. This document discusses the Border Gateway Protocol (BGP), which is an inter-Autonomous System routing protocol. The primary function of a BGP speaking system is to exchange network reachability information with other BGP systems. This network reachability information includes information on the list of Autonomous Systems (ASes) that reachability information traverses. This information is sufficient for constructing a graph of AS connectivity for this reachability from which routing loops may be pruned, and, at the AS level, some policy decisions may be enforced. BGP-4 provides a set of mechanisms for supporting Classless Inter-Domain Routing (CIDR). These mechanisms include support for advertising a set of destinations as an IP prefix, and eliminating the concept of network "class" within BGP. BGP-4 also introduces mechanisms that allow aggregation of routes, including aggregation of AS paths. This document obsoletes RFC 1771. [STANDARDS-TRACK] Many Service Providers offer Virtual Private Network (VPN) services to their customers, using a technique in which customer edge routers (CE routers) are routing peers of provider edge routers (PE routers). The Border Gateway Protocol (BGP) is used to distribute the customer's routes across the provider's IP backbone network, and Multiprotocol Label Switching (MPLS) is used to tunnel customer packets across the provider's backbone. This is known as a "BGP/MPLS IP VPN". The base specification for BGP/MPLS IP VPNs presumes that the routing protocol on the interface between a PE router and a CE router is BGP. This document extends that specification by allowing the routing protocol on the PE/CE interface to be the Open Shortest Path First (OSPF) protocol. This document updates RFC 4364. [STANDARDS-TRACK] Many Service Providers (SPs) offer Virtual Private Network (VPN) services to their customers using a technique in which Customer Edge (CE) routers are routing peers of Provider Edge (PE) routers. The Border Gateway Protocol (BGP) is used to distribute the customer's routes across the provider's IP backbone network, and Multiprotocol Label Switching (MPLS) is used to tunnel customer packets across the provider's backbone. Support currently exists for both IPv4 and IPv6 VPNs; however, only Open Shortest Path First version 2 (OSPFv2) as PE-CE protocol is specified. This document extends those specifications to support OSPF version 3 (OSPFv3) as a PE-CE routing protocol. The OSPFv3 PE-CE functionality is identical to that of OSPFv2 except for the differences described in this document. [STANDARDS-TRACK] This memo specifies an integrated routing protocol, based on the OSI Intra-Domain IS-IS Routing Protocol, which may be used as an interior gateway protocol (IGP) to support TCP/IP as well as OSI. This allows a single routing protocol to be used to support pure IP environments, pure OSI environments, and dual environments. This specification was developed by the IS-IS working group of the Internet Engineering Task Force. [STANDARDS-TRACK] This document specifies a method for exchanging IPv6 routing information using the IS-IS routing protocol. The described method utilizes two new TLVs: a reachability TLV and an interface address TLV to distribute the necessary IPv6 information throughout a routing domain. Using this method, one can route IPv6 along with IPv4 and OSI using a single intra-domain routing protocol. [STANDARDS-TRACK] This document specifies an extension of the Routing Information Protocol (RIP) to expand the amount of useful information carried in RIP messages and to add a measure of security. [STANDARDS-TRACK] This document specifies a routing protocol for an IPv6 internet. It is based on protocols and algorithms currently in wide use in the IPv4 Internet [STANDARDS-TRACK] This document describes the key chain YANG data model. Key chains are commonly used for routing protocol authentication and other applications requiring symmetric keys. A key chain is a list containing one or more elements containing a Key ID, key string, send/accept lifetimes, and the associated authentication or encryption algorithm. By properly overlapping the send and accept lifetimes of multiple key chain elements, key strings and algorithms may be gracefully updated. By representing them in a YANG data model, key distribution can be automated. This document specifies the TCP Authentication Option (TCP-AO), which obsoletes the TCP MD5 Signature option of RFC 2385 (TCP MD5). TCP-AO specifies the use of stronger Message Authentication Codes (MACs), protects against replays even for long-lived TCP connections, and provides more details on the association of security with TCP connections than TCP MD5. TCP-AO is compatible with either a static Master Key Tuple (MKT) configuration or an external, out-of-band MKT management mechanism; in either case, TCP-AO also protects connections when using the same MKT across repeated instances of a connection, using traffic keys derived from the MKT, and coordinates MKT changes between endpoints. The result is intended to support current infrastructure uses of TCP MD5, such as to protect long-lived connections (as used, e.g., in BGP and LDP), and to support a larger set of MACs with minimal other system and operational changes. TCP-AO uses a different option identifier than TCP MD5, even though TCP-AO and TCP MD5 are never permitted to be used simultaneously. TCP-AO supports IPv6, and is fully compatible with the proposed requirements for the replacement of TCP MD5. [STANDARDS-TRACK] This document introduces a collection of common data types to be used with the YANG data modeling language. This document obsoletes RFC 6021. This document defines a common YANG module that is meant to be reused by various VPN-related modules such as Layer 3 VPN and Layer 2 VPN network models. The Network Configuration Protocol (NETCONF) defined in this document provides mechanisms to install, manipulate, and delete the configuration of network devices. It uses an Extensible Markup Language (XML)-based data encoding for the configuration data as well as the protocol messages. The NETCONF protocol operations are realized as remote procedure calls (RPCs). This document obsoletes RFC 4741. [STANDARDS-TRACK] This document describes an HTTP-based protocol that provides a programmatic interface for accessing data defined in YANG, using the datastore concepts defined in the Network Configuration Protocol (NETCONF). This document describes a method for invoking and running the Network Configuration Protocol (NETCONF) within a Secure Shell (SSH) session as an SSH subsystem. This document obsoletes RFC 4742. [STANDARDS-TRACK] This document specifies version 1.3 of the Transport Layer Security (TLS) protocol. TLS allows client/server applications to communicate over the Internet in a way that is designed to prevent eavesdropping, tampering, and message forgery. This document updates RFCs 5705 and 6066, and obsoletes RFCs 5077, 5246, and 6961. This document also specifies new requirements for TLS 1.2 implementations. The standardization of network configuration interfaces for use with the Network Configuration Protocol (NETCONF) or the RESTCONF protocol requires a structured and secure operating environment that promotes human usability and multi-vendor interoperability. There is a need for standard mechanisms to restrict NETCONF or RESTCONF protocol access for particular users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. This document defines such an access control model. This document obsoletes RFC 6536. This document describes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas. YANG is a data modeling language used to model configuration and state data manipulated by the Network Configuration Protocol (NETCONF), NETCONF remote procedure calls, and NETCONF notifications. [STANDARDS-TRACK] Informative References This document describes a method by which a Service Provider may use an IP backbone to provide IP Virtual Private Networks (VPNs) for its customers. This method uses a "peer model", in which the customers' edge routers (CE routers) send their routes to the Service Provider's edge routers (PE routers); there is no "overlay" visible to the customer's routing algorithm, and CE routers at different sites do not peer with each other. Data packets are tunneled through the backbone, so that the core routers do not need to know the VPN routes. [STANDARDS-TRACK] Orange Telefonica Nokia Huawei Nokia This document defines a YANG data model for representing an abstract view of the provider network topology that contains the points from which its services can be attached (e.g., basic connectivity, VPN, network slices). Also, the model can be used to retrieve the points where the services are actually being delivered to customers (including peer networks). This document augments the 'ietf-network' data model by adding the concept of Service Attachment Points (SAPs). The SAPs are the network reference points to which network services, such as Layer 3 Virtual Private Network (L3VPN) or Layer 2 Virtual Private Network (L2VPN), can be attached. One or multiple services can be bound to the same SAP. Both User-Network Interface (UNI) and Network-to- Network Interface (NNI) are supported in the SAP data model. This document describes an architecture for the specification, creation, and ongoing maintenance of Service Function Chains (SFCs) in a network. It includes architectural concepts, principles, and components used in the construction of composite services through deployment of SFCs, with a focus on those to be standardized in the IETF. This document does not propose solutions, protocols, or extensions to existing protocols. Orange Juniper Telefonica Nokia Huawei Technologies This document specifies a YANG service data model for Attachment Circuits (ACs). This model can be used for the provisioning of ACs prior or during service provisioning (e.g., Network Slice Service). The document specifies also a module that updates other service and network modules with the required information to bind specific services to ACs that are created using the AC service model. Also, the document specifies the common AC module, which is designed with the intent to be reusable. Whether a service model reuses structures defined in the AC models or simply include an AC reference is a design choice of these service models. Relying upon the AC service model to manage ACs over which a service is delivered has the merit to decorrelate the management of a service vs. upgrade the AC components to reflect recent AC technologies or features. Each AC is identified with a unique identifier within a domain. The mapping between this AC and a network node (typically, a Provider Edge (PE)) that terminates an AC is hidden to the application/ customer that makes use of the AC service model. Such an information is internal to the network controller. Thus, the details about the (network node-specific) attachment interfaces are not exposed in this service model. Huawei Technologies Huawei Technologies Ciena Cisco Systems, Inc China Mobile Cisco Systems, Inc This document defines a YANG model for the IETF Network Slice service. The model can be used by an IETF Network Slice customer to manage IETF Network Slices. Orange Juniper Telefonica Nokia Huawei Technologies This document specifies a network model for attachment circuits. The model can be used for the provisioning of attachment circuits prior or during service provisioning (e.g., Network Slice Service). A companion service model is specified in [I-D.boro-opsawg-teas-attachment-circuit]. The module augments the Service Attachment Point (SAP) model with the detailed information for the provisioning of attachment circuits in Provider Edges (PEs). This document captures the current syntax used in YANG module tree diagrams. The purpose of this document is to provide a single location for this definition. This syntax may be updated from time to time based on the evolution of the YANG language. As a complement to the Layer 3 Virtual Private Network Service Model (L3SM), which is used for communication between customers and service providers, this document defines an L3VPN Network Model (L3NM) that can be used for the provisioning of Layer 3 Virtual Private Network (L3VPN) services within a service provider network. The model provides a network-centric view of L3VPN services. The L3NM is meant to be used by a network controller to derive the configuration information that will be sent to relevant network devices. The model can also facilitate communication between a service orchestrator and a network controller/orchestrator. This document describes a data model for the management of the Routing Information Protocol (RIP). Both RIP version 2 and RIPng are covered. The data model includes definitions for configuration, operational state, and Remote Procedure Calls (RPCs). The YANG data model in this document conforms to the Network Management Datastore Architecture (NMDA).

Tree Structure The full tree of the "ietf-ac-common" module is shown in .

AC Common Full Tree Structure

Acknowledgments TBC.

Contributors Nokia

victor.lopez@nokia.com

Ribbon Communications

Ivan.Bykov@rbbn.com

Huawei

bill.wu@huawei.com