TAPI Topology & Connectivity Enhancements Proposal for v3.0 Karthik Sethuraman, NEC Aug 13, 2019 *animated

TAPI 2.2 v/s RFC8345 Topology Models: Simplified View Composition (YANG list) Aggregation (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) Topology Network Link Link Node Node NodeEdgePoint TerminationPoint 2..* 2 Tapi 2.2 Topology RFC 8345 Topology * all TAPI & RFC 8345 associations not shown

TAPI 3.0 & RFC8345 Topology Models: Merge Proposal – opt1 Composition (YANG list) Aggregation (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) Augment TopologyContext Topology Network Augment Topology Link Link Augment Link Node Node Augment Node NodeEdgePoint TerminationPoint Augment NodeEdgePoint 2..* 2 2..* Tapi 2.2 Topology RFC 8345 Topology Tapi 3.0 Topology * all TAPI & RFC 8345 associations not shown

TAPI 3.0 & RFC8345 Topology Models: Merge Proposal – opt2 Composition (YANG list) Aggregation (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) Augment TopologyContext Topology Network Augment Topology Link Link Augment Link Node Node Augment Node NodeEdgePoint TerminationPoint Augment NodeEdgePoint 2..* 2 Tapi 2.2 Topology RFC 8345 Topology Tapi 3.0 Topology * all TAPI & RFC 8345 associations not shown

Topology & Connectivity Concepts

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 04` 01`` 01` 01.n Node-C appears a Topology of Nodes C.1-C.4 & Links between them 04 B 02.1 03 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 Connection A appears a route of Connections B,C and Link B-C C.3 C.4 C.1 C.2 11 14 16 17 18 12 13 15 04` 01`` Connection C appears as a route of Connections C.1,C.3,C.4 & in-between Links 01` 01.n 04 B 02.1 C 03 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 A A A 01 01 01 02 02 02 A A B B B 02 02 02 02 03 03 03 03 C C C 01 01 01 Node A&C Topologies always needs to be fully expanded to access NEPs 01, 02 04 04 04 C C C1 C1 C1 01 01 01 01 11 11 11 10 12 11 C3 C3 C2 13 13 13 12 14 14 14 13 C4 C4 C4 04 04 04 04 18 18 18 05

example1: 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

example2: Single-level Topology, Network 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 Probably not an very useful example, although allowed by TAPI model – serves as a base for following 2 practical sub-cases Exposes “Cross” Connections only – NO top-level Node or top-level “Network” Connection or its Connection-topology/route C.1.1 21 C.1.3 01 01 26 10 22 02 C.1.2 25 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 13 34 35 TAPI Context

example2a: 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 C.1.3 01 21 01 26 10 22 02 C.1.2 25 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 13 34 35 TAPI Context

example2b: 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 C.1.3 01 21 01 26 10 22 02 C.1.2 25 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 Network Topology 13 34 35 TAPI Context

example3: 2-level Topology, (explicit) Node + Network 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 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 12 C.2.1 31 32 33 C.2.3 36 C.2.2 13 34 35 TAPI Context

example4: Multi-level Partitioning Topology 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 01 A 02 01 02 Topology exposes Boundary NEPS 04 03 C B 02 01 01 04 03 02 Topology A Node aggregates NEPs exposed by Encapsulated Topology Topology C 02 01 01 C.1 01 C.4 10 05 04 04 11 C.3 08 C.2 12 06 07 13 C.1.1 01 21 C.1.3 26 10 10 01 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 11 12 12 Topology C.2 C.2.1 31 32 33 C.2.2 C.2.3 36 13 34 13 TAPI Context 35