Internet-Draft | A YANG Network Model for ACs | February 2024 |
Boucadair, et al. | Expires 12 August 2024 | [Page] |
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.ietf-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 note is to be removed before publishing as an RFC.¶
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 https://mailarchive.ietf.org/arch/browse/opsawg/.¶
Source for this draft and an issue tracker can be found at https://github.com/boucadair/attachment-circuit-model.¶
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 12 August 2024.¶
Copyright (c) 2024 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.¶
Connectivity services are provided by networks to customers via dedicated terminating points, such as Service Functions [RFC7665], customer edges (CEs), peer Autonomous System Border Routers (ASBRs), data centers gateways, or Internet Exchange Points.¶
The procedure to provision a service in a service provider network may depend on the practices adopted by a service provider, including the flow put in place for the provisioning of advanced network services and how they are bound to an Attachment Circuit (AC). For example, the same attachment circuit may host multiple services (e.g., Layer 2 Virtual Private Network (VPN), Slice Service, or Layer 3 VPN). In order to avoid service interference and redundant information in various locations, a service provider may expose an interface to manage ACs network-wide. Customers can then request a standalone attachment circuit to be put in place, and then refer to that attachment circuit when requesting services to be bound to that AC. [I-D.ietf-opsawg-teas-attachment-circuit] specifies a data model for managing attachment circuits as a service.¶
Section 5 specifies a network model for attachment circuits ("ietf-ac-ntw"). The model can be used for the provisioning of ACs prior or during service provisioning.¶
The document leverages [RFC9182] and [RFC9291] by adopting an AC provisioning structure that uses data nodes that are defined in these RFCs. Some refinements were introduced to cover, not only conventional service provider networks, but also specifics of other target deployments (cloud, for example).¶
The AC network model is designed as an augmnetation to the Service Attachment Point (SAP) model [RFC9408]. An attachment circuit can be bound to a single or multiple SAPs. Likewise, the model is designed to accomdate deployments where a SAP can be bound to one or multiple ACs (e.g., a parent AC and its child ACs).¶
The AC network model uses the AC common model defined in [I-D.ietf-opsawg-teas-common-ac].¶
The YANG data model in this document conforms to the Network Management Datastore Architecture (NMDA) defined in [RFC8342].¶
Sample examples are provided in Appendix A.¶
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.¶
The reader should be familiar with the terms defined in Section 2 of [RFC9408].¶
This document uses the term "network model" as defined in Section 2.1 of [RFC8969].¶
The meanings of the symbols in the YANG tree diagrams are defined in [RFC8340].¶
In addition, this document uses the following terms:¶
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 then 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 Virtual Local Area Networks (VLANs) on the same bearer that is provided by a physical link).¶
Denotes a functional entity responsible for the management of the service provider network. One or multiple network controllers can be deployed in a service provider network.¶
Refers to a functional entity that interacts with the customer of a network service.¶
A service orchestrator is typically responsible for the attachment circuits, the Provider Edge (PE) selection, and requesting the activation of the requested services to a network controller.¶
A service orchestrator may interact with one or more network controllers.¶
A network that is able to provide network services (e.g., L2VPN, L3VPN, or Network Slice Services).¶
A service provider that offers network services (e.g., L2VPN, L3VPN, or Network Slice Services).¶
Figure 2 shows the positioning of the AC network model in the overall service delivery process. The "ietf-ac-ntw" module is a network model which augments the SAP with a comprehensive set of parameters to reflect the attachment circuits that are in place in a network. The model also maintains the mapping with the service references that are used to expose these ACs to customers. Whether the same naming conventions to reference an AC are used in the service and network layers is deployment-specific.¶
Similar to [RFC9408], the "ietf-ac-ntw" module can be used for both User-to-Network Interface (UNI) and Network-to-Network Interface (NNI). For example, all the ACs shown in Figure 3 have a 'role' set to "ietf-sap-ntw:nni". Typically, AS Border Routers (ASBRs) of each network is directly connected to an ASBR of a neighboring network via one or multiple links (bearers). ASBRs of "Network#1" behaves as a PE and treats the other adjacent ASBRs as if it were a CE.¶
The full tree diagram of the module can be generated using the "pyang" tool [PYANG]. That tree is not included here because it is too long (Section 3.3 of [RFC8340]). Instead, subtrees are provided in the following subsections for the reader's convenience.¶
The overall tree structure of the module is shown in Figure 4.¶
The full tree of the 'ac-ntw' is provided in [AC-Ntw-Tree].¶
A node can host one or more SAPs. As per [RFC9408], a SAP is an abstraction of the network reference points (the PE side of an AC, in the context of this document) where network services can be delivered and/or are delivered to customers. Each SAP terminates one or multiple ACs. Each AC in turn may be terminated by one or more peer SAPs ('peer-sap'). In order to expose such AC/SAP binding information, the SAP model [RFC9408] is augmented with required AC-related information.¶
Unlike the AC service model [I-D.ietf-opsawg-teas-attachment-circuit], an AC is uniquely identified by a name within the scope of a node, not a network. A textual description of the AC may be provided ('description').¶
Also, in order to ease the correlation between the AC exposed at the service layer and the one that is actually provisioned in the network operation, a reference to the AC exposed to the customer ('ac-svc-ref') is stored in the 'ietf-ac-ntw' module.¶
ACs that are terminated by a SAP are listed in 'ac' under '/nw:networks/nw:network/nw:node/sap:service/sap:sap'. A controller may indicate a filter based on the service type (e.g., Network Slice or L3VPN) to retrieve the list of available SAPs, and thus ACs, for that service.¶
In order to factorize common data that is provisioned for a group of ACs, a set of profiles (Section 4.3) can be defined at the network level, and then called under the node level. The information contained in a profile is thus inherited, unless the corresponding data node is refined at the AC level. In such a case, the value provided at the AC level takes precedence over the global one.¶
In contexts where the same AC is terminated by multiple peer SAPs (e.g., an AC with multiple CEs) but a subset of them have specific information, the module allows operators to:¶
Define a parent AC that may list all these CEs as peer SAPs.¶
Create individual ACs that are bound to the parent AC using 'ac-parent-ref'.¶
Indicate for each individual ACs one or a subset of the CEs as peer SAPs. All these individual ACs will inherit the properties of the parent AC.¶
Whenever a parent AC is deleted, then all child ACs of that AC MUST be deleted.¶
An AC may belong to one or multiple groups [RFC9181]. For example, the 'group-id' is used to associate redundancy or protection constraints with ACs.¶
The status of an AC can be tracked using 'status'. Both operational status and administrative status are maintained. A mismatch between the administrative status vs. the operational status can be used as a trigger to detect anomalies.¶
An AC can be characterized using Layer 2 connectivity (Section 4.4), Layer 3 connectivity (Section 4.5), routing protocols (Section 4.6), OAM (Section 4.7), security (Section 4.8), and service (Section 4.9) considerations.¶
The AC module defines a set of groupings depicted in Figure 5 for referencing purposes. These references are used within or outside the AC network module. The use of such groupings is consistent with the design in [RFC8345].¶
The groupings shown in Figure 5 contain the information necessary to reference:¶
an attachment circuit that is terminated by a specific node in a given network,¶
an attachment circuit profile of a specific network (Section 4.3), and¶
specific provisioning profiles that are bound to a specific network (Section 4.3).¶
The AC and specific provisioning profiles tree structure is shown in Figure 6.¶
The exact definition of the specific provisioning profiles profiles is local to each service provider. The model only includes an identifier for these profiles in order to ease identifying and binding local policies when building an AC. As shown in Figure 6, the following identifiers can be included:¶
An encryption profile refers to a set of policies related to the encryption schemes and setup that can be applied on the AC.¶
A Quality of Service (QoS) profile refers to a set of policies such as classification, marking, and actions (e.g., [RFC3644]).¶
A Bidirectional Forwarding Detection (BFD) profile refers to a set of BFD policies [RFC5880] that can be invoked when building an AC.¶
A forwarding profile refers to the policies that apply to the forwarding of packets conveyed over an AC. Such policies may consist of, for example, applying Access Control Lists (ACLs).¶
A routing profile refers to a set of routing policies that will be invoked (e.g., BGP policies) for an AC.¶
The 'l2-connection' container is used to manage the Layer 2 properties of an AC. The Layer 2 connection tree structure is shown in Figure 7.¶
The 'encapsulation' container specifies the Layer 2 encapsulation to use (if any) and allows the configuration of the relevant tags. Also, the model supports tag manipulation operations (e.g., tag rewrite).¶
The 'l2-tunnel-service' container is used to specify the required parameters to set a Layer tunneling service (e.g., a Virtual Private LAN Service (VPLS), a Virtual eXtensible Local Area Network (VXLAN), or a pseudowire (Section 6.1 of [RFC8077])). 'l2vpn-id' is used to identify a L2VPN service that is associated with an Integrated Routing and Bridging (IRB) interface.¶
To accommodate implementations that require internal bridging, a local bridge reference can be specified in 'local-bridge-reference'. Such a reference may be a local bridge domain.¶
A reference to the bearer is maintained using 'bearer-reference'.¶
This 'ip-connection' container is used to group Layer 3 connectivity information, particularly the IP addressing information, of an AC.¶
The Layer 3 connection tree structure is shown in Figure 8.¶
A distinct Layer 3 interface other than the interface indicated under the 'l2-connection' container may be needed to terminate the Layer 3 connectivity. The identifier of such an interface is included in 'l3-termination-point'. For example, this data node can be used to carry the identifier of a bridge domain interface.¶
This container can include IPv4, IPv6, or both if dual-stack is enabled. For both IPv4 and IPv6, the IP connection supports three IP address assignment modes for customer addresses: provider DHCP, DHCP relay, and static addressing. Note that for the IPv6 case, Stateless Address Autoconfiguration (SLAAC) [RFC4862] can be used.¶
For both IPv4 and IPv6, 'address-allocation-type' is used to indicate the IP address allocation mode to activate for an AC. The allocated address represents the PE interface address configuration. When 'address-allocation-type' is set to 'provider-dhcp', DHCP assignments can be made locally or by an external DHCP server. Such behavior is controlled by setting 'dhcp-service-type'.¶
For IPv6, if 'address-allocation-type' is set to 'slaac', the Prefix Information option of Router Advertisements that will be issued for SLAAC purposes will carry the IPv6 prefix that is determined by 'local-address' and 'prefix-length'. For example, if 'local-address' is set to '2001:db8:0:1::1' and 'prefix-length' is set to '64', the IPv6 prefix that will be used is '2001:db8:0:1::/64'.¶
In some deployment contexts (e.g., network merging), multiple IP subnets may be used in a transition period. For such deployments, multiple ACs (typically, two) with overlapping information may be maintained during a transition period. The correlation between these ACs may rely upon the same "ac-svc-ref".¶
The overall routing subtree structure is shown in Figure 9.¶
Multiple routing instances ('routing-protocol') can be defined, each uniquely identified by an 'id'. Specifically, each instance is uniquely identified to accommodate scenarios where multiple instances of the same routing protocol have to be configured on the same AC.¶
The type of a routing instance is indicated in 'type'. The values of this attribute are those defined in [RFC9181] (the 'routing-protocol-type' identity). Specific data nodes are then provided as a function of the 'type'. See more details in the following subsections.¶
One or multiple routing profiles ('routing-profiles') can be provided for a given routing instance.¶
The static routing subtree structure is shown in Figure 10.¶
The following data nodes can be defined for a given IP prefix:¶
Indicates a local tag (e.g., "myfavorite-lan") that is used to enforce local policies.¶
Indicates the next hop to be used for the static route.¶
It can be identified by an IP address, a predefined next-hop type (e.g., 'discard' or 'local-link'), etc.¶
Indicates whether BFD is enabled or disabled for this static route entry. A BFD profile may also be provided.¶
Indicates the metric associated with the static route entry. This metric is used when the route is exported into an IGP.¶
Indicates the preference associated with the static route entry.¶
This preference is used to select a preferred route among routes to the same destination prefix.¶
Used to convey the status of a static route entry. This data node can also be used to control the (de)activation of individual static route entries.¶
The BGP routing subtree structure is shown in Figure 11.¶
The following data nodes are supported for each 'peer-group':¶
Defines a name for the peer group.¶
Specifies an address or a reference to an interface to use when establishing the BGP transport session.¶
Includes a description of the peer group.¶
Lists a set of import/export policies [RFC9067] to apply for this group.¶
Indicates a local AS Number (ASN).¶
Indicates the peer's ASN.¶
Indicates the address family of the peer. It can be set to 'ipv4', 'ipv6', or 'dual-stack'.¶
This address family might be used together with the service type that uses an AC (e.g., 'vpn-type' [RFC9182]) to derive the appropriate Address Family Identifiers (AFIs) / Subsequent Address Family Identifiers (SAFIs) that will be part of the derived device configurations (e.g., unicast IPv4 MPLS L3VPN (AFI,SAFI = 1,128) as defined in Section 4.3.4 of [RFC4364]).¶
Indicates the number of allowed IP hops to reach a BGP peer.¶
If set, this parameter indicates whether ASN override is enabled, i.e., replacing the ASN of the customer specified in the AS_PATH BGP attribute with the ASN identified in the 'local- as' attribute.¶
Used in some topologies (e.g., hub-and-spoke) to allow the provider's ASN to be included in the AS_PATH BGP attribute received from a peer. Loops are prevented by setting 'allow-own-as' to a maximum number of the provider's ASN occurrences. By default, this parameter is set to '0' (that is, reject any AS_PATH attribute that includes the provider's ASN).¶
When distinct ASNs are configured at the node and AC levels, this parameter controls whether the ASN provided at the node level is prepended to the AS_PATH attribute.¶
Controls whether default routes can be advertised to the peer.¶
Meant to uniquely identify the set of routes learned from a site via a particular AC. It is used to prevent routing loops (Section 7 of [RFC4364]). The Site of Origin attribute is encoded as a Route Origin Extended Community.¶
Carries an IPv6 Address Specific BGP Extended Community that is used to indicate the Site of Origin [RFC5701]. It is used to prevent routing loops.¶
Controls whether the AC is advertised to other PEs.¶
'bgp-max-prefix': Controls the behavior when a prefix maximum is reached.¶
Indicates the maximum number of BGP prefixes allowed in a session for this group. If the limit is reached, the action indicated in 'violate-action' will be followed.¶
A warning notification is triggered when this limit is reached.¶
Indicates which action to execute when the maximum number of BGP prefixes is reached. Examples of such actions include sending a warning message, discarding extra paths from the peer, or restarting the session.¶
Indicates, in seconds, the time interval after which the BGP session will be reestablished.¶
Two timers can be captured in this container: (1) 'hold-time', which is the time interval that will be used for the Hold Timer (Section 4.2 of [RFC4271]) when establishing a BGP session and (2) 'keepalive', which is the time interval for the KeepaliveTimer between a PE and a BGP peer (Section 4.4 of [RFC4271]).¶
Both timers are expressed in seconds.¶
Specifies a set of BGP capabilities (e.g., route refresh capability [RFC2918]) to be enabled per address family.¶
Indicates whether BFD is enabled or disabled for this nighbor. A BFD profile to apply may also be provided.¶
The module adheres to the recommendations in Section 13.2 of [RFC4364], as it allows enabling the TCP Authentication Option (TCP-AO) [RFC5925] and accommodates the installed base that makes use of MD5. In addition, the module includes a provision for using IPsec.¶
This version of the 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 [RFC8177], mainly SendID and RecvID (Section 3.1 of [RFC5925]).¶
For each neighbor, the following data nodes are supported in addition to similar parameters that are provided for a peer group:¶
The OSPF routing subtree structure is shown in Figure 12.¶
The following OSPF data nodes are supported:¶
Indicates whether IPv4, IPv6, or both address families are to be activated.¶
When the IPv4 or dual-stack address family is requested, it is up to the implementation (e.g., network orchestrator) to decide whether OSPFv2 [RFC4577] or OSPFv3 [RFC6565] is used to announce IPv4 routes.¶
Indicates the OSPF Area ID.¶
Associates a metric with OSPF routes.¶
Used to create OSPF sham links between two ACs sharing the same area and having a backdoor link (Section 4.2.7 of [RFC4577] and Section 5 of [RFC6565]).¶
Sets the maximum number of Link State Advertisements (LSAs) that the OSPF instance will accept.¶
Controls the authentication schemes to be enabled for the OSPF instance. The following options are supported: IPsec for OSPFv3 authentication [RFC4552], and the Authentication Trailer for OSPFv2 [RFC5709] [RFC7474] and OSPFv3 [RFC7166].¶
Indicates the status of the OSPF routing instance.¶
The IS-IS routing subtree structure is shown in Figure 13.¶
The following IS-IS data nodes are supported:¶
Indicates whether IPv4, IPv6, or both address families are to be activated.¶
Indicates the IS-IS area address.¶
Indicates the IS-IS level: Level 1, Level 2, or both.¶
Associates a metric with IS-IS routes.¶
Indicates the IS-IS interface mode type. It can be set to 'active' (that is, send or receive IS-IS protocol control packets) or 'passive' (that is, suppress the sending of IS-IS updates through the interface).¶
'authentication':¶
Controls the authentication schemes to be enabled for the IS-IS instance. Both the specification of a key chain [RFC8177] and the direct specification of key and authentication algorithms are supported.¶
Indicates the status of the IS-IS routing instance.¶
The RIP routing subtree structure is shown in Figure 14.¶
The following RIP data nodes are supported:¶
Indicates whether IPv4, IPv6, or both address families are to be activated. This parameter is used to determine whether RIPv2 [RFC2453], RIP Next Generation (RIPng), or both are to be enabled [RFC2080].¶
Indicates the following timers (expressed in seconds):¶
Sets the default RIP metric.¶
Controls the authentication schemes to be enabled for the RIP instance.¶
Indicates the status of the RIP routing instance.¶
The VRRP subtree structure is shown in Figure 15.¶
The following VRRP data nodes are supported:¶
Indicates whether IPv4, IPv6, or both address families are to be activated. Note that VRRP version 3 [RFC5798] supports both IPv4 and IPv6.¶
Used to identify the VRRP group.¶
Carries the IP address of the peer.¶
Includes virtual IP addresses for a single VRRP group.¶
Assigns the VRRP election priority for the backup virtual router.¶
Controls whether the VRRP speaker should reply to ping requests.¶
Indicates the status of the VRRP instance.¶
Note that no authentication data node is included for VRRP, as there isn't any type of VRRP authentication at this time (see Section 9 of [RFC5798]).¶
The OAM subtree structure is shown in Figure 16.¶
The following OAM data nodes can be specified for each BFD session:¶
Specifies the BFD peer address.¶
Specifies the local IP address or interface to use for the session.¶
Refers to a BFD profile (Section 4.3).¶
Includes a network reference to uniquely identify a BFD profile.¶
Indicates which BFD flavor is used to set up the session (e.g., classic BFD [RFC5880], Seamless BFD [RFC7880]). By default, it is assumed that the BFD session will follow the behavior specified in [RFC5880].¶
The minimum interval, in microseconds, to use when transmitting BFD Control packets, less any jitter applied.¶
The minimum interval, in microseconds, between received BFD Control packets less any jitter applied by the sender.¶
The negotiated transmit interval, multiplied by this value, provides the detection time for the peer.¶
Used to indicate the expected BFD holddown time, in milliseconds.¶
Includes the required information to enable the BFD authentication modes discussed in Section 6.7 of [RFC5880]. In particular, 'meticulous' controls the activation of meticulous mode as discussed in Sections 6.7.3 and 6.7.4 of [RFC5880].¶
Indicates the status of BFD.¶
The security subtree structure is shown in Figure 17. The 'security' container specifies the authentication and the encryption to be applied to traffic for a given AC. Tthe model can be used to directly control the encryption to be applied (e.g., Layer 2 or Layer 3 encryption) or invoke a local encryption profile.¶
The service subtree structure is shown in Figure 18.¶
The description of the service data nodes is as follows:¶
Specifies the Layer 2 MTU, in bytes, for the VPN network access.¶
Specify the service bandwidth for the L2VPN service.¶
'svc-pe-to-ce-bandwidth' indicates the inbound bandwidth of the connection (i.e., download bandwidth from the service provider to the site).¶
'svc-ce-to-pe-bandwidth' indicates the outbound bandwidth of the connection (i.e., upload bandwidth from the site to the service provider).¶
'svc-pe-to-ce-bandwidth' and 'svc-ce-to-pe-bandwidth' can be represented using the Committed Information Rate (CIR), the Excess Information Rate (EIR), or the Peak Information Rate (PIR).¶
The following types, defined in [RFC9181], can be used to indicate the bandwidth type:¶
Specifies a list of QoS profiles to apply for this AC.¶
Specifies a list of ACL profiles to apply for this AC.¶
This module uses types defined in [RFC6991], [RFC8177], [RFC8294], [RFC8343], [RFC9067], [RFC9181], [I-D.ietf-opsawg-teas-common-ac], and [IEEE802.1Qcp].¶
<CODE BEGINS> file "ietf-ac-ntw@2022-11-30.yang" module ietf-ac-ntw { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-ac-ntw"; prefix ac-ntw; import ietf-vpn-common { prefix vpn-common; reference "RFC 9181: A Common YANG Data Model for Layer 2 and Layer 3 VPNs"; } import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types, Section 4"; } import ietf-key-chain { prefix key-chain; reference "RFC 8177: YANG Data Model for Key Chains"; } import ietf-routing-types { prefix rt-types; reference "RFC 8294: Common YANG Data Types for the Routing Area"; } import ietf-routing-policy { prefix rt-pol; reference "RFC 9067: A YANG Data Model for Routing Policy"; } import ietf-interfaces { prefix if; reference "RFC 8343: A YANG Data Model for Interface Management"; } import ieee802-dot1q-types { prefix dot1q-types; reference "IEEE Std 802.1Qcp: Bridges and Bridged Networks-- Amendment 30: YANG Data Model"; } import ietf-network { prefix nw; reference "RFC 8345: A YANG Data Model for Network Topologies, Section 6.1"; } import ietf-sap-ntw { prefix sap; reference "RFC 9408: A YANG Network Model for Service Attachment Points (SAPs)"; } import ietf-ac-common { prefix ac-common; reference "RFC CCCC: A Common YANG Data Model for Attachment Circuits"; } import ietf-ac-svc { prefix ac-svc; reference "RFC SSSS: YANG Service Data Models for Attachment Circuits"; } organization "IETF OPSAWG (Operations and Management Area Working Group)"; contact "WG Web: <https://datatracker.ietf.org/wg/opsawg/> WG List: <mailto:opsawg@ietf.org> Editor: Mohamed Boucadair <mailto:mohamed.boucadair@orange.com> Author: Richard Roberts <mailto:rroberts@juniper.net> Author: Oscar Gonzalez de Dios <mailto:oscar.gonzalezdedios@telefonica.com> Author: Samier Barguil <mailto:ssamier.barguil_giraldo@nokia.com> Author: Bo Wu <mailto:lana.wubo@huawei.com>"; description "This YANG module defines a YANG network model for the management of attachment circuits. Copyright (c) 2024 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; revision 2023-11-13 { description "Initial revision."; reference "RFC XXXX: A YANG Network Data Model for Attachment Circuits"; } // References /* A set of groupings to ease referencing cross-modules */ grouping attachment-circuit-reference { description "This grouping can be used to reference an attachment circuit in a specific node."; leaf ac-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]/nw:node[nw:node-id=current()/../" + "node-ref]/ac-ntw:ac/ac-ntw:name"; require-instance false; } description "A type for an absolute reference to an attachment circuit."; } uses nw:node-ref; } grouping ac-profile-reference { description "This grouping can be used to reference an attachment circuit profile."; leaf ac-profile-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]/ac-ntw:ac-profile/ac-ntw:name"; require-instance false; } description "A type for an absolute reference to an attachment circuit."; } uses nw:network-ref; } grouping encryption-profile-reference { description "This grouping can be used to reference encryption profile."; leaf encryption-profile-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]" + "/ac-ntw:specific-provisioning-profiles" + "/ac-ntw:valid-provider-identifiers" + "/ac-ntw:encryption-profile-identifier/ac-ntw:id"; require-instance false; } description "A type for an absolute reference to an encryption profile."; } uses nw:network-ref; } grouping qos-profile-reference { description "This grouping can be used to reference a QoS profile."; leaf qos-profile-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]" + "/ac-ntw:specific-provisioning-profiles" + "/ac-ntw:valid-provider-identifiers" + "/ac-ntw:qos-profile-identifier/ac-ntw:id"; require-instance false; } description "A type for an absolute reference to a QoS profile."; } uses nw:network-ref; } grouping bfd-profile-reference { description "This grouping can be used to reference a BFD profile."; leaf bfd-profile-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]" + "/ac-ntw:specific-provisioning-profiles" + "/ac-ntw:valid-provider-identifiers" + "/ac-ntw:bfd-profile-identifier/ac-ntw:id"; require-instance false; } description "A type for an absolute reference to a BFD profile."; } uses nw:network-ref; } grouping forwarding-profile-reference { description "This grouping can be used to reference a forwarding profile."; leaf forwarding-profile-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]" + "/ac-ntw:specific-provisioning-profiles" + "/ac-ntw:valid-provider-identifiers" + "/ac-ntw:forwarding-profile-identifier/ac-ntw:id"; require-instance false; } description "A type for an absolute reference to a forwarding profile."; } uses nw:network-ref; } grouping routing-profile-reference { description "This grouping can be used to reference a routing profile."; leaf routing-profile-ref { type leafref { path "/nw:networks/nw:network[nw:network-id=current()/../" + "network-ref]" + "/ac-ntw:specific-provisioning-profiles" + "/ac-ntw:valid-provider-identifiers" + "/ac-ntw:routing-profile-identifier/ac-ntw:id"; require-instance false; } description "A type for an absolute reference to a routing profile."; } uses nw:network-ref; } // L2 conenction grouping l2-connection { description "Defines Layer 2 protocols and parameters that are required to enable AC connectivity."; container encapsulation { description "Container for Layer 2 encapsulation."; leaf encap-type { type identityref { base vpn-common:encapsulation-type; } description "Tagged interface type."; } container dot1q { when "derived-from-or-self(../encap-type, " + "'vpn-common:dot1q')" { description "Only applies when the type of the tagged interface is 'dot1q'."; } description "Tagged interface."; uses ac-common:dot1q; container tag-operations { description "Sets the tag manipulation policy for this AC. It defines a set of tag manipulations that allow for the insertion, removal, or rewriting of 802.1Q VLAN tags. These operations are indicated for the CE-PE direction. By default, tag operations are symmetric. As such, the reverse tag operation is assumed on the PE-CE direction."; choice op-choice { description "Selects the tag rewriting policy for an AC."; leaf pop { type empty; description "Pop the outer tag."; } leaf push { type empty; description "Pushes one or two tags defined by the tag-1 and tag-2 leaves. It is assumed that, absent any policy, the default value of 0 will be used for the PCP setting."; } leaf translate { type empty; description "Translates the outer tag to one or two tags. PCP bits are preserved."; } } leaf tag-1 { when 'not(../pop)'; type dot1q-types:vlanid; description "A first tag to be used for push or translate operations. This tag will be used as the outermost tag as a result of the tag operation."; } leaf tag-1-type { type dot1q-types:dot1q-tag-type; default "dot1q-types:s-vlan"; description "Specifies a specific 802.1Q tag type of tag-1."; } leaf tag-2 { when '(../translate)'; type dot1q-types:vlanid; description "A second tag to be used for translation."; } leaf tag-2-type { type dot1q-types:dot1q-tag-type; default "dot1q-types:c-vlan"; description "Specifies a specific 802.1Q tag type of tag-2."; } } } container priority-tagged { when "derived-from-or-self(../encap-type, " + "'vpn-common:priority-tagged')" { description "Only applies when the type of the tagged interface is 'priority-tagged'."; } description "Priority tagged container."; uses ac-common:priority-tagged; } container qinq { when "derived-from-or-self(../encap-type, " + "'vpn-common:qinq')" { description "Only applies when the type of the tagged interface is 'QinQ'."; } description "Includes QinQ parameters."; uses ac-common:qinq; container tag-operations { description "Sets the tag manipulation policy for this AC. It defines a set of tag manipulations that allow for the insertion, removal, or rewriting of 802.1Q VLAN tags. These operations are indicated for the CE-PE direction. By default, tag operations are symmetric. As such, the reverse tag operation is assumed on the PE-CE direction."; choice op-choice { description "Selects the tag rewriting policy for a AC."; leaf pop { type uint8 { range "1|2"; } description "Pops one or two tags as a function of the indicated pop value."; } leaf push { type empty; description "Pushes one or two tags defined by the tag-1 and tag-2 leaves. It is assumed that, absent any policy, the default value of 0 will be used for PCP setting."; } leaf translate { type uint8 { range "1|2"; } description "Translates one or two outer tags. PCP bits are preserved. The following operations are supported: - translate 1 with tag-1 leaf is provided: only the outermost tag is translated to the value in tag-1. - translate 2 with both tag-1 and tag-2 leaves are provided: both outer and inner tags are translated to the values in tag-1 and tag-2, respectively. - translate 2 with tag-1 leaf is provided: the outer tag is popped while the inner tag is translated to the value in tag-1."; } } leaf tag-1 { when 'not(../pop)'; type dot1q-types:vlanid; description "A first tag to be used for push or translate operations. This tag will be used as the outermost tag as a result of the tag operation."; } leaf tag-1-type { type dot1q-types:dot1q-tag-type; default "dot1q-types:s-vlan"; description "Specifies a specific 802.1Q tag type of tag-1."; } leaf tag-2 { when 'not(../pop)'; type dot1q-types:vlanid; description "A second tag to be used for push or translate operations."; } leaf tag-2-type { type dot1q-types:dot1q-tag-type; default "dot1q-types:c-vlan"; description "Specifies a specific 802.1Q tag type of tag-2."; } } } } choice l2-service { description "The Layer 2 connectivity service can be provided by indicating a pointer to an L2VPN or by specifying a Layer 2 tunnel service."; container l2-tunnel-service { description "Defines a Layer 2 tunnel termination."; uses ac-common:l2-tunnel-service; } case l2vpn { leaf l2vpn-id { type vpn-common:vpn-id; description "Indicates the L2VPN service associated with an Integrated Routing and Bridging (IRB) interface."; } } } } grouping l2-connection-if-ref { description "Specifies Layer 2 connection paramters with interface references."; uses l2-connection; leaf l2-termination-point { type string; description "Specifies a reference to a local Layer 2 termination point, such as a Layer 2 sub-interface."; } leaf local-bridge-reference { type string; description "Specifies a local bridge reference to accommodate, e.g., implementations that require internal bridging. A reference may be a local bridge domain."; } leaf bearer-reference { if-feature "vpn-common:bearer-reference"; type string; description "This is an internal reference for the service provider to identify the bearer associated with this AC."; } container lag-interface { if-feature "vpn-common:lag-interface"; description "Container for configuration of Link Aggregation Group (LAG) interface attributes."; leaf lag-interface-id { type string; description "LAG interface identifier."; } container member-link-list { description "Container for the member link list."; list member-link { key "name"; description "Member link."; leaf name { type string; description "Member link name."; } } } } } // IPv4 connection groupings grouping ipv4-connection { description "IPv4-specific parameters."; leaf local-address { type inet:ipv4-address; description "The IP address used at the provider's interface."; } uses ac-common: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 { 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 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: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 access."; } choice service-type { description "Choice based on the DHCP service type."; case relay { description "Container for a list of the provider's DHCP servers (i.e., 'dhcp-service-type' is set to 'relay')."; leaf-list server-ip-address { type inet:ipv4-address; description "IPv4 addresses of the provider's DHCP server, for use by the local DHCP relay."; } } } } 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."; } } } } } grouping ipv6-connection { description "IPv6-specific parameters."; leaf local-address { type inet:ipv6-address; description "IPv6 address of the provider side."; } uses ac-common: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 { 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 service-type { description "Choice based on the DHCP service type."; case relay { description "Container for a list of the provider's DHCP servers (i.e., 'dhcp-service-type' is set to 'relay')."; leaf-list server-ip-address { type inet:ipv6-address; description "IPv6 addresses of the provider's DHCP server, for use by the local DHCP relay."; } } } } 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 IPv4 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 address of the connection."; leaf address-id { type string; description "An identifier of the static IPv4 address."; } leaf customer-address { type inet:ipv6-address; description "An IPv6 address of the customer side."; } } } } } grouping ip-connection { description "Defines IP connection parameters."; leaf l3-termination-point { type string; description "Specifies a reference to a local Layer 3 termination point, such as a bridge domain interface."; } container ipv4 { if-feature "vpn-common:ipv4"; description "IPv4-specific parameters."; uses ipv4-connection; } container ipv6 { if-feature "vpn-common:ipv6"; description "IPv6-specific parameters."; uses ipv6-connection; } } /* Routing */ //BGP base parameters grouping bgp-base { description "Configuration specific to BGP."; leaf description { type string; description "Includes a description of the BGP session. This description is meant to be used for diagnostic purposes. The semantic of the description is local to an implementation."; } uses rt-pol:apply-policy-group; leaf local-as { type inet:as-number; description "Indicates a local AS Number (ASN), if an ASN distinct from the ASN configured at the AC level is needed."; } leaf peer-as { type inet:as-number; mandatory true; 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."; } leaf multihop { type uint8; description "Describes the number of IP hops allowed between a given BGP neighbor and the PE."; } leaf as-override { type boolean; description "Defines whether ASN override is enabled, i.e., replacing the ASN of the customer specified in the AS_PATH attribute with the local ASN."; } leaf allow-own-as { type uint8; description "If set, specifies the maximum number of occurrences of the provider's ASN that are permitted within the AS_PATH before it is rejected."; } leaf prepend-global-as { type boolean; description "In some situations, the ASN that is provided at the node level may be distinct from the ASN configured at the AC. When such ASNs are provided, they are both prepended to the BGP route updates for this AC. To disable that behavior, 'prepend-global-as' must be set to 'false'. In such a case, the ASN that is provided at the node level is not prepended to the BGP route updates for this access."; } leaf send-default-route { type boolean; description "Defines whether default routes can be advertised to a peer. If set, the default routes are advertised to a peer."; } leaf site-of-origin { when "derived-from-or-self(../address-family, 'vpn-common:ipv4'" + " or 'vpn-common:dual-stack')" { description "Only applies if IPv4 is activated."; } type rt-types:route-origin; description "The Site of Origin attribute is encoded as a Route Origin Extended Community. It is meant to uniquely identify the set of routes learned from a site via a particular AC and is used to prevent routing loops."; reference "RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs), Section 7"; } leaf ipv6-site-of-origin { when "derived-from-or-self(../address-family, 'vpn-common:ipv6'" + " or 'vpn-common:dual-stack')" { description "Only applies if IPv6 is activated."; } type rt-types:ipv6-route-origin; description "The IPv6 Site of Origin attribute is encoded as an IPv6 Route Origin Extended Community. It is meant to uniquely identify the set of routes learned from a site."; reference "RFC 5701: IPv6 Address Specific BGP Extended Community Attribute"; } list redistribute-connected { key "address-family"; description "Indicates, per address family, the policy to follow for connected routes."; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates the address family."; } leaf enabled { type boolean; description "Enables the redistribution of connected routes."; } } container bgp-max-prefix { description "Controls the behavior when a prefix maximum is reached."; leaf max-prefix { type uint32; description "Indicates the maximum number of BGP prefixes allowed in the BGP session. It allows control of how many prefixes can be received from a neighbor. If the limit is exceeded, the action indicated in 'violate-action' will be followed."; reference "RFC 4271: A Border Gateway Protocol 4 (BGP-4), Section 8.2.2"; } leaf warning-threshold { type decimal64 { fraction-digits 5; range "0..100"; } units "percent"; description "When this value is reached, a warning notification will be triggered."; } leaf violate-action { type enumeration { enum warning { description "Only a warning message is sent to the peer when the limit is exceeded."; } enum discard-extra-paths { description "Discards extra paths when the limit is exceeded."; } enum restart { description "The BGP session restarts after the indicated time interval."; } } description "If the BGP neighbor 'max-prefix' limit is reached, the action indicated in 'violate-action' will be followed."; } leaf restart-timer { type uint32; units "seconds"; description "Time interval after which the BGP session will be reestablished."; } } container bgp-timers { description "Includes two BGP timers."; leaf keepalive { type uint16 { range "0..21845"; } units "seconds"; description "This timer indicates the KEEPALIVE messages' frequency between a PE and a BGP peer. If set to '0', it indicates that KEEPALIVE messages are disabled. It is suggested that the maximum time between KEEPALIVE messages be one-third of the Hold Time interval."; reference "RFC 4271: A Border Gateway Protocol 4 (BGP-4), Section 4.4"; } leaf hold-time { type uint16 { range "0 | 3..65535"; } units "seconds"; description "Indicates the maximum number of seconds that may elapse between the receipt of successive KEEPALIVE and/or UPDATE messages from the peer. The Hold Time must be either zero or at least three seconds."; reference "RFC 4271: A Border Gateway Protocol 4 (BGP-4), Section 4.2"; } } list capability { key "address-family"; description "Customized set of BGP capabilities per address family."; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates the address family."; } leaf name { type identityref { base ac-common:bgp-capability; } mandatory true; description "Indicates the name of BGP capability."; } } } // RIP base parameters grouping rip-base { description "Configuration specific to RIP routing."; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates whether IPv4, IPv6, or both address families are to be activated."; } container timers { description "Indicates the RIP timers."; reference "RFC 2453: RIP Version 2"; leaf update-interval { type uint16 { range "1..32767"; } units "seconds"; description "Indicates the RIP update time, i.e., the amount of time for which RIP updates are sent."; } leaf invalid-interval { type uint16 { range "1..32767"; } units "seconds"; description "The interval before a route is declared invalid after no updates are received. This value is at least three times the value for the 'update-interval' argument."; } leaf holddown-interval { type uint16 { range "1..32767"; } units "seconds"; description "Specifies the interval before better routes are released."; } leaf flush-interval { type uint16 { range "1..32767"; } units "seconds"; description "Indicates the RIP flush timer, i.e., the amount of time that must elapse before a route is removed from the routing table."; } } leaf default-metric { type uint8 { range "0..16"; } description "Sets the default metric."; } } // routing profile grouping routing-profile { description "Defines routing protocols."; list routing-protocol { key "id"; description "List of routing protocols used on the AC."; leaf id { type string; description "Unique identifier for the routing protocol."; } leaf type { type identityref { base vpn-common:routing-protocol-type; } description "Type of routing protocol."; } container bgp { when "derived-from-or-self(../type, " + "'vpn-common:bgp-routing')" { description "Only applies when the protocol is BGP."; } description "Configuration specific to BGP."; uses bgp-base; } container ospf { when "derived-from-or-self(../type, " + "'vpn-common:ospf-routing')" { description "Only applies when the protocol is OSPF."; } description "Configuration specific to OSPF."; uses ac-common:ospf-basic; leaf max-lsa { type uint32 { range "1..4294967294"; } description "Maximum number of allowed Link State Advertisements (LSAs) that the OSPF instance will accept."; } } container isis { when "derived-from-or-self(../type, " + "'vpn-common:isis-routing')" { description "Only applies when the protocol is IS-IS."; } description "Configuration specific to IS-IS."; uses ac-common:isis-basic; leaf level { type identityref { base vpn-common:isis-level; } description "Can be 'level-1', 'level-2', or 'level-1-2'."; reference "RFC 9181: A Common YANG Data Model for Layer 2 and Layer 3 VPNs"; } leaf metric { type uint16; description "Metric of the AC. It is used in the routing state calculation and path selection."; } leaf mode { type enumeration { enum active { description "The interface sends or receives IS-IS protocol control packets."; } enum passive { description "Suppresses the sending of IS-IS updates through the specified interface."; } } description "IS-IS interface mode type."; } } container rip { when "derived-from-or-self(../type, " + "'vpn-common:rip-routing')" { description "Only applies when the protocol is RIP."; } description "Configuration specific to RIP routing."; uses rip-base; } container vrrp { when "derived-from-or-self(../type, " + "'vpn-common:vrrp-routing')" { description "Only applies when the protocol is the Virtual Router Redundancy Protocol (VRRP)."; } description "Configuration specific to VRRP."; reference "RFC 5798: Virtual Router Redundancy Protocol (VRRP) Version 3 for IPv4 and IPv6"; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates whether IPv4, IPv6, or both address families are to be enabled."; } leaf ping-reply { type boolean; description "Controls whether the VRRP speaker should reply to ping requests."; } } } } grouping routing { description "Defines routing protocols."; list routing-protocol { key "id"; description "List of routing protocols used on the AC."; leaf id { type string; description "Unique identifier for the routing protocol."; } leaf type { type identityref { base vpn-common:routing-protocol-type; } description "Type of routing protocol."; } list routing-profile { key "routing-profile-ref"; description "Routing profiles."; uses routing-profile-reference; leaf type { type identityref { base vpn-common:ie-type; } description "Import, export, or both."; } } container static { when "derived-from-or-self(../type, " + "'vpn-common:static-routing')" { description "Only applies when the protocol is a static routing protocol."; } description "Configuration specific to static routing."; container cascaded-lan-prefixes { description "LAN prefixes from the customer."; list ipv4-lan-prefix { if-feature "vpn-common:ipv4"; key "lan next-hop"; description "List of LAN prefixes for the site."; uses ac-common:ipv4-static-rtg-entry; uses bfd-routing; leaf preference { type uint32; description "Indicates the preference associated with the static route."; } uses ac-common:service-status; } list ipv6-lan-prefix { if-feature "vpn-common:ipv6"; key "lan next-hop"; description "List of LAN prefixes for the site."; uses ac-common:ipv4-static-rtg-entry; uses bfd-routing; leaf preference { type uint32; description "Indicates the preference associated with the static route."; } uses ac-common:service-status; } } } container bgp { when "derived-from-or-self(../type, " + "'vpn-common:bgp-routing')" { description "Only applies when the protocol is BGP."; } description "Configuration specific to BGP."; container peer-groups { description "Configuration for BGP peer-groups"; list peer-group { key "name"; description "List of BGP peer-groups configured on the local system - uniquely identified by peer-group name"; leaf name { type string; description "Name of the BGP peer-group"; } leaf local-address { type union { type inet:ip-address; type if:interface-ref; } description "Sets the local IP address to use for the BGP transport session. This may be expressed as either an IP address or a reference to an interface."; } uses bgp-base; uses ac-common:bgp-authentication; } } list neighbor { key "remote-address"; description "List of BGP neighbors."; leaf remote-address { type inet:ip-address; description "The remote IP address of this entry's BGP peer."; } leaf local-address { type union { type inet:ip-address; type if:interface-ref; } description "Sets the local IP address to use for the BGP transport session. This may be expressed as either an IP address or a reference to an interface."; } leaf peer-group { type leafref { path "../../peer-groups/peer-group/name"; } description "The peer-group with which this neighbor is associated."; } uses bgp-base; uses bfd-routing; uses ac-common:bgp-authentication; uses ac-common:service-status; } } container ospf { when "derived-from-or-self(../type, " + "'vpn-common:ospf-routing')" { description "Only applies when the protocol is OSPF."; } description "Configuration specific to OSPF."; uses ac-common:ospf-basic; container sham-links { if-feature "vpn-common:rtg-ospf-sham-link"; description "List of sham links."; reference "RFC 4577: OSPF as the Provider/Customer Edge Protocol for BGP/MPLS IP Virtual Private Networks (VPNs), Section 4.2.7 RFC 6565: OSPFv3 as a Provider Edge to Customer Edge (PE-CE) Routing Protocol, Section 5"; list sham-link { key "target-site"; description "Creates a sham link with another site."; leaf target-site { type string; description "Target site for the sham link connection. The site is referred to by its identifier."; } leaf metric { type uint16; description "Metric of the sham link. It is used in the routing state calculation and path selection."; reference "RFC 4577: OSPF as the Provider/Customer Edge Protocol for BGP/MPLS IP Virtual Private Networks (VPNs), Section 4.2.7.3 RFC 6565: OSPFv3 as a Provider Edge to Customer Edge (PE-CE) Routing Protocol, Section 5.2"; } } } leaf max-lsa { type uint32 { range "1..4294967294"; } description "Maximum number of allowed Link State Advertisements (LSAs) that the OSPF instance will accept."; } uses ac-common:ospf-authentication; uses ac-common:service-status; } container isis { when "derived-from-or-self(../type, " + "'vpn-common:isis-routing')" { description "Only applies when the protocol is IS-IS."; } description "Configuration specific to IS-IS."; uses ac-common:isis-basic; leaf level { type identityref { base vpn-common:isis-level; } description "Can be 'level-1', 'level-2', or 'level-1-2'."; reference "RFC 9181: A Common YANG Data Model for Layer 2 and Layer 3 VPNs"; } leaf metric { type uint16; description "Metric of the PE-CE link. It is used in the routing state calculation and path selection."; } leaf mode { type enumeration { enum active { description "The interface sends or receives IS-IS protocol control packets."; } enum passive { description "Suppresses the sending of IS-IS updates through the specified interface."; } } description "IS-IS interface mode type."; } uses ac-common:isis-authentication; uses ac-common:service-status; } container rip { when "derived-from-or-self(../type, " + "'vpn-common:rip-routing')" { description "Only applies when the protocol is RIP. For IPv4, the model assumes that RIP version 2 is used."; } description "Configuration specific to RIP routing."; uses rip-base; uses ac-common:rip-authentication; uses ac-common:service-status; } container vrrp { when "derived-from-or-self(../type, " + "'vpn-common:vrrp-routing')" { description "Only applies when the protocol is the VRRP."; } description "Configuration specific to VRRP."; reference "RFC 5798: Virtual Router Redundancy Protocol (VRRP) Version 3 for IPv4 and IPv6"; leaf address-family { type identityref { base vpn-common:address-family; } description "Indicates whether IPv4, IPv6, or both address families are to be enabled."; } leaf vrrp-group { type uint8 { range "1..255"; } description "Includes the VRRP group identifier."; } leaf backup-peer { type inet:ip-address; description "Indicates the IP address of the peer."; } leaf-list virtual-ip-address { type inet:ip-address; description "Virtual IP addresses for a single VRRP group."; reference "RFC 5798: Virtual Router Redundancy Protocol (VRRP) Version 3 for IPv4 and IPv6, Sections 1.2 and 1.3"; } leaf priority { type uint8 { range "1..254"; } description "Sets the local priority of the VRRP speaker."; } leaf ping-reply { type boolean; description "Controls whether the VRRP speaker should reply to ping requests."; } uses ac-common:service-status; } } } // OAM grouping bfd { description "Grouping for BFD."; leaf session-type { type identityref { base vpn-common:bfd-session-type; } description "Specifies the BFD session type."; } leaf desired-min-tx-interval { type uint32; units "microseconds"; description "The minimum interval between transmissions of BFD Control packets, as desired by the operator."; reference "RFC 5880: Bidirectional Forwarding Detection (BFD), Section 6.8.7"; } leaf required-min-rx-interval { type uint32; units "microseconds"; description "The minimum interval between received BFD Control packets that the PE should support."; reference "RFC 5880: Bidirectional Forwarding Detection (BFD), Section 6.8.7"; } leaf local-multiplier { type uint8 { range "1..255"; } description "Specifies the detection multiplier that is transmitted to a BFD peer. The detection interval for the receiving BFD peer is calculated by multiplying the value of the negotiated transmission interval by the received detection multiplier value."; reference "RFC 5880: Bidirectional Forwarding Detection (BFD), Section 6.8.7"; } 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."; reference "RFC 5880: Bidirectional Forwarding Detection (BFD), Section 6.8.18"; } } grouping bfd-routing { description "Defines a basic BFD grouping for routing configuration."; container bfd { description "BFD control for this nighbor."; leaf enable { type boolean; description "Enables BFD if set to true. BFD is disabled of set to false."; } uses bfd-profile-reference; } } // OAM grouping oam { description "Defines the Operations, Administration, and Maintenance (OAM) mechanisms used."; container bfd { description "Container for BFD."; list session { key "dest-addr"; description "List of IP sessions."; leaf dest-addr { type inet:ip-address; description "IP address of the peer."; } leaf source-address { type union { type inet:ip-address; type if:interface-ref; } description "Sets the local IP address to use for the BFD session. This may be expressed as either an IP address or a reference to an interface."; } uses bfd-profile-reference; uses bfd; container authentication { presence "Enables BFD authentication"; description "Parameters for BFD authentication."; leaf key-chain { type key-chain:key-chain-ref; description "Name of the key chain."; } leaf meticulous { type boolean; description "Enables meticulous mode."; reference "RFC 5880: Bidirectional Forwarding Detection (BFD), Section 6.7"; } } uses ac-common:service-status; } } } // security grouping security { description "Security parameters for an AC."; container encryption { if-feature "vpn-common:encryption"; description "Container for AC encryption."; leaf enabled { type boolean; description "If set to 'true', traffic encryption on the connection is required. Otherwise, it is disabled."; } leaf layer { when "../enabled = 'true'" { description "Included only when encryption is enabled."; } type enumeration { enum layer2 { description "Encryption occurs at Layer 2."; } enum layer3 { description "Encryption occurs at Layer 3. For example, IPsec may be used when a customer requests Layer 3 encryption."; } } description "Indicates the layer on which encryption is applied."; } } container encryption-profile { when "../encryption/enabled = 'true'" { description "Indicates the layer on which encryption is enabled."; } description "Container for the encryption profile."; choice profile { description "Choice for the encryption profile."; case provider-profile { uses encryption-profile-reference; } case customer-profile { leaf customer-key-chain { type key-chain:key-chain-ref; description "Customer-supplied key chain."; } } } } } // AC profile grouping ac-profile { description "Grouping for attachment circuit profiles."; container routing-protocols { description "Defines routing protocols."; uses routing-profile; } container oam { description "Defines the OAM mechanisms used for the AC profile."; container bfd { if-feature "vpn-common:bfd"; description "Container for BFD."; uses bfd; } } } // AC network provisioning grouping ac { description "Grouping for attachment circuits."; leaf description { type string; description "Associates a description with an AC."; } container l2-connection { description "Defines Layer 2 protocols and parameters that are required to enable AC connectivity."; uses l2-connection-if-ref; } container ip-connection { description "Defines IP connection parameters."; uses ip-connection; } container routing-protocols { description "Defines routing protocols."; uses routing; } container oam { description "Defines the OAM mechanisms used for the AC."; uses oam; } container security { description "AC-specific security parameters."; uses security; } container service { description "AC-specific bandwith parameters."; leaf mtu { type uint32; units "bytes"; description "Layer 2 MTU."; } uses ac-svc:bandwidth; container qos { if-feature "vpn-common:qos"; description "QoS configuration."; container qos-profiles { description "QoS profile configuration."; list qos-profile { key "qos-profile-ref"; description "Points to a QoS profile."; uses qos-profile-reference; leaf direction { type identityref { base vpn-common:qos-profile-direction; } description "The direction to which the QoS profile is applied."; } } } } container access-control-list { description "Container for the Access Control List (ACL)."; container acl-profiles { description "ACL profile configuration."; list acl-profile { key "forwarding-profile-ref"; description "Points to an ACL profile."; uses forwarding-profile-reference; } } } } } augment "/nw:networks/nw:network" { description "Add a list of profiles."; container specific-provisioning-profiles { description "Contains a set of valid profiles to reference in the AC activation."; uses ac-common:ac-profile-cfg; } list ac-profile { key "name"; description "Specifies a list of AC profiles."; leaf name { type string; description "Name of the AC."; } uses ac-ntw:ac-profile; } } augment "/nw:networks/nw:network/nw:node" { when '../nw:network-types/sap:sap-network' { description "Augmentation parameters apply only for SAP networks."; } description "Augments nodes with AC provisioning details."; list ac { key "name"; description "List of ACs."; leaf name { type string; description "A name that identifies the AC locally."; } leaf ac-svc-ref { type ac-svc:attachment-circuit-reference; description "A reference to the AC as exposed at the service level."; } list ac-profile { key "ac-profile-ref"; description "List of AC profiles."; uses ac-profile-reference; } container ac-parent-ref { description "Specifies the parent AC that is inherited by an AC. Parent ACs are used, e.g., in contexts where multiple CEs are terminating the same AC, but some specific information is required for each peer SAP."; uses ac-ntw:attachment-circuit-reference; } leaf-list peer-sap-id { type string; description "One or more peer SAPs can be indicated."; } list group { key "group-id"; description "List of group-ids."; leaf group-id { type string; description "Indicates the group-id to which the AC belongs."; } leaf precedence { type identityref { base ac-common:precedence-type; } description "Defines redundancy of an AC."; } } uses ac-common:service-status; uses ac-ntw:ac; } } augment "/nw:networks/nw:network/nw:node" + "/sap:service/sap:sap" { when '../../../nw:network-types/sap:sap-network' { description "Augmentation parameters apply only for SAP networks."; } description "Augments SAPs with AC provisioning details."; list ac { key "ac-ref"; description "Specifies the ACs that are terminated by the SAP."; uses ac-ntw:attachment-circuit-reference; } } } <CODE ENDS>¶
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.¶
There are a number of 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) and delete operations to these data nodes without proper protection or authentication can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/ vulnerability in the "ietf-ac-ntw" module:¶
This container includes a set of sensitive data that influence how an AC is delivered. For example, an attacker who has access to these data nodes may be able to manipulate routing policies, QoS policies, or encryption properties. These data nodes are defined with "nacm:default-deny- write" tagging [I-D.ietf-opsawg-teas-common-ac].¶
An attacker who is able to access network nodes can undertake various attacks, such as modify the attributes of an AC (e.g., QoS, bandwidth, routing protocols, keying material), leading to malfunctioning of services that are delivered over that AC and therefore to Service Level Agreement (SLA) violations. In addition, an attacker could attempt to add a new AC. : In addition to using NACM to prevent unauthorized access, such activity can be detected by adequately monitoring and tracking network configuration changes.¶
Some of 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 in the "ietf-ac-svc" module:¶
Unauthorized access to this subtree can disclose the identity of a customer 'peer-sap-id'.¶
An attacker can retrieve privacy-related information, which can be used to track a customer. Disclosing such information may be considered a violation of the customer-provider trust relationship.¶
An attacker can retrieve the cryptographic keys protecting an AC (routing, in particular). These keys could be used to inject spoofed routing advertisements.¶
Several data nodes ('bgp', 'ospf', 'isis', and 'rip') rely upon [RFC8177] for authentication purposes. As such, the AC network module inherits the security considerations discussed in Section 5 of [RFC8177]. Also, these data nodes 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 AC network model, because it is not supported by the underlying device modules (e.g., [RFC8695]).¶
IANA is requested to register the following URI in the "ns" subregistry within the "IETF XML Registry" [RFC3688]:¶
URI: urn:ietf:params:xml:ns:yang:ietf-ac-ntw Registrant Contact: The IESG. XML: N/A; the requested URI is an XML namespace.¶
IANA is requested to register the following YANG module in the "YANG Module Names" subregistry [RFC6020] within the "YANG Parameters" registry:¶
Name: ietf-ac-ntw Namespace: urn:ietf:params:xml:ns:yang:ietf-ac-ntw Prefix: ac-ntw Maintained by IANA? N Reference: RFC XXXX¶
Let's consider the example depicted in Figure 19 with two customer terminating points (CE1 and CE2). Let's also assume that the bearers to attach these CEs to the provider network are already in place. References to the identify these bearers are shown in the figure.¶
The AC service model [I-D.ietf-opsawg-teas-attachment-circuit] can be used by the provider to manage and expose the ACs over existing bearers as shown in Figure 20.¶
The provisioned AC at PE1 can be retrieved using the AC network model as depicted in Figure 21. A similar query can be used for the AC at PE2.¶
Also, the AC network model can be used to retrieve the list of SAPs to which the ACs are bound as shown in Figure 21.¶
In reference to the topology depicted in Figure 1, PE2 has a SAP which terminates an AC with two peer SAPs (CE2 and CE5). In order to control data that is specific to each of these peer SAPs over the same AC, child ACs can be instantiated as depicted in Figure 23.¶
Figure 24 shows how to bind the parent AC to a SAP.¶
This document builds on [RFC9182] and [RFC9291].¶
Thanks to Moti Morgenstern for the review and comments.¶
Thanks to Martin Björklund for the yangdoctors review.¶