I2RS | S. Hares |
Internet-Draft | L. Dunbar |
Intended status: Standards Track | Huawei |
Expires: August 13, 2016 | February 10, 2016 |
A Yang model for I2RS service topology
draft-hares-i2rs-service-topo-dm-05.txt
This document defines I2RS protocol-independent service layer virtual topology data model. This data model utilizes the concepts in the generic I2RS topology model of virtual networks (node, links, termination points) and cross-layer topologies. This virtual service topology may be a composite layer created from the combination of protocol-dependent service layers. Protocol-dependent services layers include: L3VPN, L2VPN, EVPN, E-Tree, and others.
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Service topology in [I-D.ietf-i2rs-yang-network-topo] includes the a virtual topology for a service layer above the L1, L2, and L3 layers. This virtual topology has the generic topology elements of node, link, and terminating point. The virtual service topology is a network-wide topology stored on one routing system which an I2RS agent is connected to.
The virtual service topology is a composite summary of the services available services gathered from the lower layer indications of L3VPN, L2VPN, and EVPN services, E-TREE services, Seamless MPLS topologies within an As and others. This is a "bottoms up" yang module providing composite protocol independent service topology based on these protocol services.
This "bottoms-up" yang model does provide a mechanism to link this bottoms up model to a top-down service model. One example of a top-down service model for L3 VPNs is the L3 Service yang data model [I-D.ietf-l3sm-l3vpn-service-model]. Although the two models are linked, the top-down service model cannot be derived from the lower layers.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC2119 [RFC2119].
+----------------+ | network | | topology |<... +----------------+ : * * : : | | :...: | | +--------+ +--------+ ...>| node |<.......|link |<... : +--------+<.......+--------+ : : : * : : * : : :..... | : : | :...: | : : | .....>+--------+<........: : | : | TP |<..........: | : ...>+--------+ | : : | : : .....................+---------+ .........................|Direction| +---------+
The following diagram contains an informal graphical depiction of the main elements of the information model:
The link between the upper layer and the lower layer occurs by linking the bottoms up service network topologies to Top-down service topologies at certain service nodes to support transport of service across a virtual service link.
For example, the bottoms up topology could contain a composite of 3 L3VPN network topologies, 2 L2VPN network topologies, and 2 EVPN network topologies. Each of these physical networks can support virtual networks on top of the physical network. The service network base bottoms up is formed topology map with all of these topologies.
An L3SM might utilize have three VPN services topologies which support three services over 9 virtual topologies transiting the 2 of the L3VPN networks.
The nodes providing the L3VPN provider equipment (PE) overlap, but the customer equipment (CE) at all sites are unique.
L3SM topologies Service-topology [VPN-ID:1] / \ cloud 1 topology 1 cloud 2 topology-1 / | \ / | \ Site-1A site-1B site1-C site-1A Site-1B Site-1C | | | | | | ====|==========|=======|=======|=========|=====|==== +-------+ | \ / / | Bottoms-up | | \ / / | service | | /\ / | topology | | / \ | | L3VPN-Service-topology 1 L3VPN-Service Topology-2 | | | | | | node1 node2 node3 node4 node5 node6 PE PE PE PE PE PE | | | | | | CE CE CE CE CE CE
These two layers of service topologies are by two different composite models composite models and different supporiting models as follows:
The links between
This section describes the Yang High level architecture.
The service topology network level defines the following high-level yang architeture:
module: i2rs-service-topologies augment /nw:network/nw:network-types: +--rw service-topologies-types augment /nw:network: +--rw service-topology-attributes +--rw name? string +--rw flag flag_type; +--rw composite-flag identity-ref +--rw c-service-topo-id network-id +--rw c-servic-id uint32 +--rw c-node-cnt uint32 +--rw composite-flag_status identity-ref +--rw supports-td-attributes* Note: Composite flags are bottoms-up flags
The service topology attributes for a network include the following
module: i2rs-service-topologies .... augment /nw:network/nw:node +--rw node-service-attributes +--rw c-svc-node-name? inet:domain-name +--rw c-svc-flag* identityref; +--rw c-service-node-id uint32 +--rw c-svc-node-type identityref +--rw c-node-svc-status* identityref; +--rw c-node-supports-td-attributes
The additional fields in the service attributes are the following:
augment /nw:network/nt:link: +--rw service-link-attributes +--rw c-svc-link-name? string +--rw c-svc-link-id uint32 +--rw c-svc-link-type identityref +--rw c-svc-link-metric? uint32 +--rw c-svc-link-attributes* identityref +--rw c-svc-link-td-supports-attr* identityref augment /nw:network/nw:node/nt:termination-point: +--rw service-termination-point-attributes +--rw tp-svc-id +--rw (supporting-termination-point) +--:(service) | +--rw service-network-id leafref | +--rw service-node-id leafref | +--rw service-tp-id leafref +--:(ip) | +--rw ip-address inet:ip-address +--:(unnumbered) +--rw unnumbered-id? uint32
The augmentation to the service topology is the service link attributes which include:
The augmentation to the termination point include the following
<CODE BEGINS> file "ietf-i2rs-service-topology@2016-02-09.yang" module ietf-i2rs-service-topology{ namespace "urn:ietf:params:xml:ns:yang:ietf-i2rs-service-topology"; prefix i2rs-st; import ietf-inet-types { prefix inet; } import ietf-network { prefix nw; } import ietf-network-topology { prefix "nt"; } organization "IETF"; contact "email: shares@ndzh.com; email: linda.dunbar@huawei.com; "; description "This module defines a model for the service topology. This service model imports - ietf-network and ietf-network-topology from draft-ietf-i2rs-yang-network-topo-02.txt, - ietf-routing from draft-ietf-netmod-routing-cfg, - ietf-l3vpn-svc from draft-ietf-l3sm-l3vpn-service-model. (not defined yet ) "; revision 2016-02-09 { description "Version 1 - initial version; Version 2 - yang format fixed Version 3 - errro in xml file version 4 - remove next-hops attribute. version 5- links to top-level attributes."; reference "draft-hares-i2rs-service-topo-dm-05.txt"; } identity svc-topo-flag-identity { description "Base type for svc flags"; } identity l3vpn-svc-topo { base svc-topo-flag-identity; description "L3VPN service type"; } identity l2vpn-svc-topo { base svc-topo-flag-identity; description "L2VPN service type"; } identity EVPN-svc-topo { base svc-topo-flag-identity; description "EVPN service type"; } identity Seamless-MPLS-svc-topo { base svc-topo-flag-identity; description "Seamless MPLS service type"; } identity Etree-svc-topo { base svc-topo-flag-identity; description "Seamless MPLS service type"; } identity I2rs-svc-topo { base svc-topo-flag-identity; description "I2RS create service topo"; } identity svc-tp-type { description "Base type for service termination-point type flags"; } identity svc-tp-type-service { base svc-tp-type; description "service type"; } identity svc-tp-type-ip { base svc-tp-type; description "service IP"; } identity svc-tp-type-unnum { base svc-tp-type; description "service unnumbered link"; } identity service-topology-types{ description "service topology type"; } identity svc-link-identity { description "Base type for composite service link attribute flags"; } identity svc-link-ip-te { base svc-tp-type; description "service link that support IP traffic engineering"; } identity svc-link-ip-multicast { base svc-tp-type; description "service link that supports IP multicast."; } identity td-svc-support-identity { description "Base type for svc flags"; } identity td-L3sm-hub-spoke { base td-svc-support-identity; description "Supports L3SM hub-spoke"; } identity td-L3sm-hub-spoke-disjoint { base td-svc-support-identity; description "Supports L3SM hub-spoke disjoint"; } identity td-L3sm-any-any { base td-svc-support-identity; description "Supports L3SM any-any"; } grouping service-topology-types { leaf service-type { type identityref { base svc-topo-flag-identity; } description "list of service topology type supported"; } description "service topology types"; } grouping service-topology-attributes { leaf name { type string; description "name of service topology"; } leaf composite-flag { type identityref { base service-topology-types; } description "other topologies this topology is configured to be a composite of (L3VPN, L2VPN, I2RS only)"; } leaf c-service-topo-id { type nw:network-id; description "service topology id to a service topology instance."; } leaf c-service-id-number { type uint32; description "ID for topology"; } leaf c-node-count { type uint32; description "count of service level nodes in the network."; } leaf composite-flag-status { type identityref { base svc-topo-flag-identity;} description "other topologies this topology is currently a composite of (L3VPN, L2VPN, I2RS only)"; } list supports-td-attributes { key c-svc-td-attribute-id; leaf c-svc-td-attribute-id { type uint8; description "top-down service support attribute id number"; } leaf td-supports-attribute { type identityref { base td-svc-support-identity; } description "top-down service attribute this topology supports."; } description "supporting top-down service attributes. "; } description "Group of attributes for service topology"; } grouping node-svc-attribute { leaf c-svc-node-name{ type inet:domain-name; description "Domain name for node"; } leaf c-svc-flag { type identityref { base svc-topo-flag-identity; } description "virtual network node can be composite of the topologies list (L3VPN, L2VPN, I2RS only)"; } leaf c-svc-node-id { type uint32; description "ID for node at service level"; } leaf node-svc-status { type identityref { base service-topology-types; } description "other topologies this topology is currewntly be composed of (L3VPN, L2VPN, I2RS only)"; } list c-node-supports-td-attributes { key c-node-td-attribute-id; leaf c-node-td-attribute-id { type uint8; description "top-down service support attribute id number"; } leaf c-node-supports-attribute { type identityref { base td-svc-support-identity; } description "top-down service attribute this topology supports."; } description "list of top-down service attributes this node supports"; } description "grouping of composite flag"; } grouping service-link-attributes { leaf c-svc-link-name { type string; description "name of service link"; } leaf c-svc-link-id { type uint32; description "link id"; } leaf c-svc-link-type { type identityref { base service-topology-types; } description "other topologies this link is current a composite of (L3VPN, L2VPN, I2RS only)"; } leaf c-svc-link-metric { type uint32; description "link metric which may need to expand or link to TE topologies."; } list c-svc-link-attributes { key c-svcl-attr-id; leaf c-svcl-attr-id { type uint8; description "composite service attribute id number"; } leaf c-svc-link-attribute { type identityref { base svc-link-identity; } description "top-down service attribute this link supports."; } description "list of service level link attributes"; } list c-svc-link-td-supports-attributes { key c-svcl-td-attr-id; leaf c-svcl-td-attr-id { type uint8; description "top-down service support attribute id number"; } leaf c-svc-link-td-support-attribute { type identityref { base td-svc-support-identity; } description "top-down service attribute this link supports."; } description "list of service level link attributes"; } description "grouping of service link attribute"; } grouping service-termination-point-attributes { leaf svc-tp-id { type uint32; description "termination point id"; } container supporting-termination-point { leaf svc-tp-type { type identityref { base svc-tp-type; } description "other topologies this link termination point is part of (L3VPN, L2VPN, or I2RS only)"; } choice svc-tp-support-type{ case svc-tp-type-service { leaf service-network-id { type uint32; description "service network id"; } leaf service-node-id { type uint32; description "service node id"; } leaf service-link-id { type uint32; description "service link id"; } description "network, node, tp that supports this termination point"; } case svc-tp-type-inet { leaf ip-address{ type inet:ip-address; description "ip address"; } description "inet svc tp"; } case svc-tp-type-unnum { leaf unnumbered-id { type uint32; description "unnumbered id"; } description "unnumber svc tp"; } description "service termination point type cases"; } description "container of supporting termination point"; } description "grouping of service-termination-point-attributes"; } /* * Data nodes */ augment "/nw:networks/nw:network/nw:network-types"{ uses service-topology-types; description "augment the network-tpyes with the service-topology-types grouping"; } augment "/nw:networks/nw:network/nw:node" { leaf name { type inet:domain-name; description "service name."; } list composite_flag { key "service-node-id"; leaf service-node-id{ type uint32; description "service node id."; } leaf node-svc-type{ type string; description "node service type."; } description "the list of composite flag."; } description "augments node list"; } augment "/nw:networks/nw:network"{ uses service-topology-attributes; description "augment the network with the servcie-topolgoy-attributes"; } augment "/nw:networks/nw:network/nw:node"{ uses node-svc-attribute; description "augment the node with the node-svc-attribute"; } augment "/nw:networks/nw:network/nt:link" { uses service-link-attributes; description "augment the link with service-link-attributes"; } augment "/nw:networks/nw:network/nw:node/nt:termination-point"{ uses service-termination-point-attributes; description "augment the termination-point with service-termination-point-attributes"; } } // module i2rs-service-topology <CODE ENDS>
TBD
TBD
[I-D.ietf-i2rs-yang-network-topo] | Clemm, A., Medved, J., Varga, R., Tkacik, T., Bahadur, N. and H. Ananthakrishnan, "A Data Model for Network Topologies", Internet-Draft draft-ietf-i2rs-yang-network-topo-02, December 2015. |
[RFC2119] | Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997. |
[I-D.ietf-i2rs-yang-l3-topology] | Clemm, A., Medved, J., Varga, R., Tkacik, T., Liu, X., Bryskin, I., Guo, A., Ananthakrishnan, H., Bahadur, N. and V. Beeram, "A YANG Data Model for Layer 3 Topologies", Internet-Draft draft-ietf-i2rs-yang-l3-topology-01, December 2015. |
[I-D.ietf-l3sm-l3vpn-service-model] | Litkowski, S., Shakir, R., Tomotaki, L. and K. D'Souza, "YANG Data Model for L3VPN service delivery", Internet-Draft draft-ietf-l3sm-l3vpn-service-model-02, December 2015. |