Karthik Sethuraman, NEC Multi-layer Multi-domain Network Topology Abstractions Using ONF Transport API Karthik Sethuraman, NEC September 2019 *animated slides

ONF Transport API (TAPI): Functional Architecture Industry Adoption: Functional Interface solution that best fulfills conflicting requirements of stability (future proof, interoperability) & flexibility/agility (technology evolution) NE Application NE SDN Controller NE NE Transport API or Other NBIs Topology Service Connectivity Service OAM Service Path Computation Service Virtual Network Service Equipment Inventory Service Notification Service Shared Network Information Context Transport API or Other SBIs Network Elements SDN Controller NE NE NE

OIF Transport API Interop Demo (2014, 2016, 2018) OSS/App/Orchestrator Transport API Test Carriers TAPI Agent Multi-Domain Controller Transport API Common Abstraction model TAPI Agent Multi-Domain Controller Transport API TAPI Agent TAPI Agent TAPI Agent Technology, Vendor Specific models Domain Controller Domain Controller Domain Controller Test Vendors

Simple Physical Network Example to illustrate T-API Node Edge Point (Network Internal) Node Edge Point (Network Edge) Service Interface Point Logical Termination Points CE2 CE5 CE – Customer Edge PE – Provider Edge P - Provider UNI PE2 CE1 CE3 PE1 PE3 CE4 CE6 UNI P4 UNI A Network Provider (Blue) with two Customers (Red and Green) All UNI interfaces are ETH (e.g. 10GE), I-NNI interfaces are OTU (e.g. 100G OTN) All PE-NE are ODU/ETH switch capable, while P-NE is only ODU switch capable

T-API Contexts for the Simple Network Example (based on ONF Architecture v1.1) Application RED SDN Controller GREEEN Admin APP Pink Resource Group Resource Group Client TAPI TAPI TAPI Shared Context RED Shared Context GREEN Shared Context PINK.Admin Resource Group Resource Group Resource Group Server Provider Internal Context Resource Groups Provider SDN Controller Orchestration / Virtualization Other Admin Interfaces Client Server Context PE1 Server Context PE2 Server Context PE3 Server Context P Resource Group - PE1 Resource Group - PE2 Resource Group - PE3 Resource Group - P Server

Example Topology Abstractions in the Shared Context Red Shared Context Node Edge Point (NW Internal) Service Interface Point Node Edge Point (NW Edge) Link Topology Node Transitional Link Mapping P PE1 PE2 PE3 Pink Admin Context G1 G2 G3 Green Shared Context

Recursive Partitioning of Node Topology within Shared Context Red Shared Context Node Edge Point (NW Internal) Service Interface Point Node Edge Point (NW Edge) Link Mapping Topology Node Red Shared Context R1 R1.2 R1.1 R1.3

Client-1 (Red) Shared Context: Single Node Topology Single Node abstraction example Node and its NodeEdgePoints provide some approximation of the network capabilities ConnectivityService can be requested between ServiceInterfacePoints Connections appear as cross-connections across node, no visibility of underlying route Node Edge Point (Internal) Node Edge Point (Edge) Service End Point Link Transitional Link Mapping Topology Node Connection EndPoint Connection Service Interface Point Shared Context Connection Connectivity Service ETH

Client 2 (Green) Shared Context: Multi-Node Topology Multiple Nodes (PEs) Topology example Node and its NodeEdgePoints provide reasonable information of their capabilities ConnectivityService can be requested between ServiceInterfacePoints Top-level Connection is recursively decomposed into lower-level Connections, 1 per Node Connection route can be traced over the exposed Topology Node Edge Point (Internal) Node Edge Point (Edge) Service End Point Link Transitional Link Mapping Topology Node Connection EndPoint Connection Service Interface Point Shared Context PE2 ETH Connection PE1 PE3 Connectivity Service

Admin (Pink) Shared Context: Multi-layer Topology Each physical device is represented by a separate Node per supported layer (ETH & ODU) Node and its NodeEdgePoints provide information of their capabilities at that layer Transitional Links interconnect the NodeEdgePoints at different layers Top-level Connection is recursively decomposed into lower-level Connections, 1 per Node Top-level Connections at lower (server) layer result in Links at upper (client) layer Node Edge Point (Internal) Node Edge Point (Edge) Service End Point Link Transitional Link Mapping Topology Node Connection EndPoint Connection Service Interface Point TAPI Context PE2e 1 2 PE1e PE3e 3 PE2o 2 1 PE1o PE3o P4o 3

Recursive Node & Topology aspects of Forwarding Domain Node aspect of FD Topology aspect of FD Observer 01 A FD (Node) Node Edge Point Link 01.1 Service Interface Point FD (Topology) Mapping TAPI Context N Context appears as a Topology N of one Node A and SIPs (off-network relationships/Links) 02` 01`` A 01.1 C Node-A appears a Topology of Nodes B & C and Link B-C C.3 C.4 C.1 C.2 11 14 16 17 18 12 13 15 03 01 01` 01.n Node-C appears a Topology of Nodes C.1-C.4 & Links between them 03` B 04 02.1 C 02 02.n

Recursive Connectivity & Topology aspects of Forwarding Node aspect of FD Topology aspect of FD Observer 01 A FD (Node) Node Edge Point Link 01.1 Service Interface Point FD (Topology) Mapping Connection Topology Connection Connection End Point TAPI Context Top-level “Network” Connection A N 02` 01`` A 01.1 C C.3 C.4 C.1 C.2 11 14 16 17 18 12 13 15 03 01 Connection A appears a route of Connections B,C and Link B-C Connection C appears as a route of Connections C.1,C.3,C.4 & in-between Links 01` 01.n 03` B 02.1 C 04 02 02.n

TAPI Topology & Connectivity Instances Tree view (example1) Topology w/ Connectivity N N Topology A 01 Node Connection Topology Connection Node Edge Point Connection End Point Reference/Pointer Composition 01` Node Edge Point Reference Connection End Point Ref A A A 01`` 01`` 01 02` 02` 02 A A B B B 02 02 02 02 04 03 04 04 C C C 01` 01 01` 03` 03 03` C C C1 C1 C1 01 01 01 01 11 11 11 11 12 12 C3 C3 C3 15 15 16 13 16 16 17 14 17 17 C4 C4 C4 04 04 04 04 18 18 18 18

Example 1: Single-level Topology, Network-Node (Single) abstraction Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service Single Node abstraction – for simple TAPI applications/clients that does not want to concern itself with Network topology & routing Ability to expose top-level “Network” Connection only – No way to represent top-level Connection’s route or its lower-level decomposed “cross” connections Node Topology A 01 02 01 02 TAPI Context

Example 2a: Single-level Topology, Network abstraction with implicit Node Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service Implicit Top-level Singe Node (and its encapsulated Topology) Provides ability to expose top-level “Network” Connection and its Connection-topology/route as well as it decomposed lower-level “Cross” Connections Top-level Connection is NOT bounded by an explicit Node, while lower-level connections have a bounding Node C.1.1 01 01 21 C.1.3 26 10 22 C.1.2 25 02 23 24 11 C.3 08 C.4 B 06 05 04 03 02 07 12 C.2.1 31 32 33 C.2.3 36 C.2.2 Network Topology 34 35 13 TAPI Context

Example 2b: Single-level Topology, Network abstraction /w multi-level implicit Nodes Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service A variation of example 2a – but with multiple levels of Implicit Nodes (and their encapsulated Topology hierarchy) Provides ability to expose top-level “Network” Connection and its Connection-topology/route as well as multiple levels of Connection decomposition Top-level Connection as well as intermediate-level connections are NOT bounded by an explicit Node, while lowest-level connections have a bounding Node C.1.1 01 01 21 C.1.3 26 10 22 C.1.2 25 02 23 24 B 11 C.3 08 C.4 03 02 06 05 04 07 12 C.2.1 31 32 33 C.2.3 36 C.2.2 35 13 34 Network Topology TAPI Context

example3: 2-level Topology, Network abstraction w/ Explicit Node Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service This abstraction emerges from example 2a, with distinction of an Explicit bounding Node for “Network” Connection which allows for clean representation of forwarding capability prior to setting up of connectivity Provides ability to expose top-level “Network” Connection and its Connection-topology/route as well as its decomposed lower-level “Cross” Connections All Connections are bounded by an explicit Node Node Topology A 01 02 01 02 Network Topology C.1.1 C.1.3 01 21 26 10 22 C.1.2 25 23 24 11 C.3 08 C.4 B 06 05 04 03 02 07 C.2.1 12 31 32 C.2.2 33 C.2.3 36 34 35 13 TAPI Context

example4: Multi-level Topology Partitioning abstraction Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service Node Topology A 01 02 Node aggregates NEPs exposed by Encapsulated Topology C B 01 04 03 02 Topology A Topology C 01 02 C.1 01 C.4 10 05 04 11 C.3 08 C.2 12 06 07 13 C.1.1 01 21 C.1.3 26 10 22 C.1.2 25 Topology C.1 23 24 Emerges from example 2b - with distinction of multiple levels of Explicit Nodes (and their encapsulated Topology hierarchy) Provides ability to expose multi-level Connections, each bounded by an explicit Node 11 C.2.1 12 Topology C.2 31 32 C.2.2 33 C.2.3 36 34 35 13 TAPI Context

TAPI 2.2.2 v/s RFC8345 Topology Models: Simplified View Composition (YANG list) Shared (YANG leafref + require_instance=true) Association (YANG leafref + require_instance=false) Augment (YANG augment + uses + container) Augment (YANG augment + uses) TapiContext (ROOT) Augment TopologyContext Networks (ROOT) * all TAPI & RFC 8345 associations not shown 0..1 Topology Network Encapsulates Topology SupportedBy Link Link SupportedBy Node Terminates On Node AggregatesNEPs ExposedBy UnderlyingTopology SupportedBy 0..* Source NodeEdgePoint TerminationPoint 2..* 0..* Destination PoolsNEPsInSameNode SupportedBy Tapi 2.2 Topology (Partitioning & Layering) RFC 8345 Topology (View mapping)

TAPI 3.0 augments RFC8345 Topology Model Composition (YANG list) Shared (YANG leafref + require_instance=true) Association (YANG leafref + require_instance=false) Augment (YANG augment + uses + container) Augment (YANG augment + uses) Augment TopologyContext Networks (ROOT) 0..1 Augment * all TAPI & RFC 8345 associations not shown Topology Network Encapsulates Topology SupportedBy Link Link SupportedBy Node Augment Node AggregatesNEPs ExposedBy UnderlyingTopology Terminates On SupportedBy 0..* Source NodeEdgePoint 2..* TerminationPoint Augment Destination 0..* SupportedBy PoolsNEPsInSameNode Tapi 2.2 Topology (Partitioning & Layering) RFC 8345 Topology (View mapping)

example5: Multi-level Topology Partitioning via Mapping abstraction Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service Node Topology A 01``` 02` NEP Supported By NEP C B 01`` 04` 03 02 Topology A Topology C 01 02 01` C.1 10` C.4 05 04 11` C.3 08 C.2 12` 06 07 13` C.1.1 01 21 C.1.3 26 10 22 C.1.2 25 Topology C.1 23 24 11 Topology C.2 C.2.1 12 Emerges from example 4 - with distinction of multiple clones NEPs & CEPs at every hierarchy level 31 32 C.2.2 33 C.2.3 36 34 35 13 TAPI Context

example6: Multiple Topology Views via Mapping abstraction Node Edge Point 01 A Node Reference (pointer) Link Topology Node Encapsulates Topology Service Interfc Point Connection End Point Connection End Point Reference (pointer) Connection Connectivity Service Provides ability to provide & map different intermediate views of an single underlying Topology Node Topology A 01`` 02` NEP Supported By NEP Topology B 01` X.1 Topology C 01 10` Y.1 Y.2 02 11` X.4 01` 06` 05` 02` 0`8 X.3 05` 02` X.2 06` 12` 07` 13` N.1 01 21 N.6 Network Topology 26 10 22 N.2 25 23 24 11 N.7 08 N.8 N.9 06 05 04 03 02 12 07 N.3 31 32 N.4 33 N.5 36 34 35 13 TAPI Context

MEF: Lifecycle Service Orchestration Reference Architecture (LSO RA) MEF Common Resource Model ONF TAPI Model

MEF: Service Provider, Operators, ICM Domains, UNI, ENNI, INNI (1) Partner Operator Operator Operator Operator ICM Domain ICM Domain ICM Domain ICM Domain ICM Domain OLS Domain UNI INNI UNI ENNI ENNI

MEF: Service Provider, Operators, ICM Domains, UNI, ENNI, INNI (3) LEGATO Create L1 VC Service Orchestration Functionality (SOF), SP Domain Create L1 OVC Create L1 OVC INTERLUDE SOF, Operator Domain SOF, Partner Operator Domain Create Connectivity Service Create Connectivity Service Create Connectivity Service PRESTO Infrastructure Control & Mng (ICM) ICM ICM Create Connectivity Service Open Line System ICM Node Node Node OLS Node UNI E-NNI I-NNI UNI

MEF: Layer 1 Service across different Operators & Management Domains managed object classes at Service level (appearing at Legato, Interlude Management IRPs) ONF TAPI managed object classes at Resource level (appearing at Presto for provisioning purposes) ONF TAPI managed object classes at Resource level (appearing at Presto for discovery purposes, e.g. topology) MEF Resource managed object classes augmenting TAPI L1 VC (the end-to-end Layer 1 Service) L1ServiceLevelSpecification L1 OVC L1 OVC L1Connectivity Resource ConnectivityService ConnectivityService ConnectivityService Connection Connection Connection Node Node Node UNI OLS Node E-NNI I-NNI UNI CEP CEP CEP CEP CEP CEP NEP NEP NEP NEP NEP NEP L1UniNResource SIP SIP L1EnniN Resource SIP SIP SIP SIP L1Connectivity EndPointResource CSEP CSEP CSEP CSEP L1InniN Resource CSEP CSEP EVC MIP EVC up MEP OVC Up MEP UNI Down MEP ENNI Down MEP SIP CSEP CEP Service Interface Point Connectivity Service End Point NEP Node Edge Point Connection End Point

ONF ODTN (Open Disaggregated Transport) Architecture With OLS Controller TAPI ONOS TAPI OLS Controller Has topology OpenConfig OpenConfig TRN MUX WSS AMP WSS MUX TRN Open Line System (OLS)

Operator Domain Topology – Partitioning to abstract layer network UNI TPD3 TPD1 TPD2 E-NNI SOF-ICM TAPI Context (LSO Presto) Operator SOF view 100G OLS Node 100G Operator ICM View 100G 100G 100G 100G 100G 100G RDM2 RDM1 RDM4 RDM3 RDM5 OLS Domain I-NNI2 I-NNI1 I-NNI3 ICM-OLS TAPI Context OLS View Node Edge Point (Network Internal) Node Edge Point (Network Edge) Service Interface Point Logical Termination Points shown Connectivity Service End Point Connection / Connection End Point Photonic Connection Photonic Media Channel Abbreviations TPD – Transponder Node RDM – ROADM Node UNI – User-Network Interface NNI – Network-Network Interface DSR – Digital Signal Rate OTSi – Optical Tributary Signal OTSiA – OTSi Assembly MC – Media Channel

Operator Domain Connectivity Service & Resources UNI TPD3 TPD1 TPD2 E-NNI SOF-ICM TAPI Context (LSO Presto) DSR Connectivity Service 1 (100G) Operator SOF view DSR Connectivity Service 2 (100G) DSR Connectivity Service 3 (100G) DSR2 100G DSR1 100G OTSiA1 200G 100G OTSi 1-1 OLS Node OTSi-MC1 OTSi 1-2 100G OTSi-MC2 Operator ICM View 100G 100G 100G OTSiA2 200G OTSi 2-1 OTSi-MC3 100G DSR3 100G OTSi 2-2 OTSi-MC4 100G 100G RDM2 RDM1 RDM4 RDM3 RDM5 OLS Domain I-NNI2 I-NNI1 I-NNI3 ICM-OLS TAPI Context OLS View Photonic Connectivity Service 1 Node Edge Point (Network Internal) Node Edge Point (Network Edge) Service Interface Point Logical Termination Points shown Connectivity Service End Point Connection / Connection End Point Photonic Connection Photonic Media Channel Photonic Connectivity Service 2 Abbreviations TPD – Transponder Node RDM – ROADM Node UNI – User-Network Interface NNI – Network-Network Interface DSR – Digital Signal Rate OTSi – Optical Tributary Signal OTSiA – OTSi Assembly MC – Media Channel OTSi-MC1 OTSi-MC2 OTSi-MC3 OTSi-MC4

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