Rationalizing ONAP Architecture for R 2 and Beyond

Rationalizing ONAP Architecture for R 2 and Beyond

ONAP R 2+ Architecture – Current Draft View VNF/PNF SDK Design-time (SDC) Resource Onboarding Service & Product Design Policy Creation & Validation Testing & Certification Analytic Application Design Catalog Products Services Resources Policies Eng. Rules Analytics Recipe / Engineering Rules & Policy Distribution Further Rationalization Opportunities ONAP Operations Management (OOM) Run-time External Data Movement & APIs Orchestration (SO) Inventory/Topology (AAI) Ø Service Level Orchestration Active / Available Entitlements Ø Resource Level Orchestration Resource / Service Topology ESR Common Services DMaa. P Multi-VIM Interface Infrastructure Adaption Layer Open Stack AAF Logging AWS Azure MEC Data & Analytics (DCAE) Policy DCAE Analytic µServices Policy Execution Engine … Holmes CDAP Data Distribution Data Collection Layer Micro Services Bus L 0 -3 Network Controller (SDN-C) L 4 -7 Controller (App-C) Config Service Logic Life Cycle Database Interpreter Mgmt Func Config Service Logic Life Cycle Database Interpreter Mgmt funcs Adaption Layer Netconf rd Yang CLI 3 Party Network controller Standard Adaption Layer Chef Netconf Ansible Vendor OA&M Adaptor Vendor VNFM Adaption Layer (VF-C) Life Cycle Mgmt funcs Vendor A B s. VNFM VNF 1 Infrastructure 2 BSS ONAP Portal – Design Studio & Dashboard VNF 2 Open. Stack VNF 3 VMware PNF 1 Rack. Space … Azure VNFn Peripherals

Open Issues: § What is the right Orchestration Implementation in ONAP & How to provide deployment flexibility? § Rationalization of Controller Family within ONAP 3

Role Of Orchestrator in ONAP: ONAP Orchestrator must orchestrate Network Functions (VNF / PNF), Services and coordinate cross-controller activities driven by orders and events that indicate the need to instantiate, modify or remove Network Functions (VNF / PNF), services as well as multicontrol layer remedy actions. Key attributes of Orchestrator are • Model Driven Orchestration ‒ ‒ ‒ Process behavior driven by resource / service model designed in SDC Orchestrates network functions and service Instantiations Support software upgrade and planned change management Support open & closed-loop control actions initiated by DCAE /Policy or external API (from OSS for Open Loop) Tracks orchestrated activity for the life of the request but doesn’t control state of orchestrated components • Interfaces to External OSS / BSS Systems ‒ Standard APIs exposed northbound to create, modify or remove services ‒ Request decomposition of service request into service / network function components ‒ Selects model / recipe that supports the request and maps order data to recipe / model • Coordinating Activities Across Various ONAP Controllers ‒ Coordinates activities across Multi-VIM (infrastructure)/SDN-C//app-C/VF-C controllers ‒ Manage recording of service configurations • Orchestrator Performs Following Additional Services ‒ ‒ Coordinates current inventories and placement/optimization recommendations Enforces business & technical policies Support standards-based workflows Validates and records network functions / service implementations 4

Examples of Orchestration Requests • Install a single network function (VNF or PNF) – e. g. Deploy a new virtual PE / P router ‒ A virtual network element might have one or more components (e. g VNFCs or VDUs) • Install multiple copies of network functions in one or more data centers – e. g. Deploy new virtual PE / P routers across n locations • Deploy one or more instances of network services – e. g. RAN at Multiple sites, one or more sites of EPC, etc. • Instantiate a customer services – e. g. multi-site VPN or IP SEC ‒ Could require deploying new instances of network elements (e. g. v. CE) and using existing elements (e. g. v. PE) ‒ Could be using existing elements without any new VNF / PNF being deployed (e. g. “Allocated Resources” – configuring a service to existing components) • Create a new instance of a network service – e. g. Io. T or e. MBB slice ‒ Could be leveraging existing network elements (RAN, v. EPC, Transport etc. ) without any new VNF / PNF being deployed • Implement a software upgrade / change management ‒ Could require Coordination of activities across Multi-VIM (infrastructure)/SDN-C/app-C/VF-C controllers • Orchestrator requested to remedial action as part of Closed or open loop action ‒ Could require adding new compute / network resource to the existing functional elements (i. e. VNF) ‒ Create a new instance of VNF and migrate traffic ‒ Could require Coordination of activities across Multi-VIM (infrastructure)/SDN-C/app-C/VF-C controllers) 5

Model-Driven Orchestration “Generic” model-driven Service flow (limited existing) Service Orchestration Resource Orchestration PNF Service X: topology_template: node_templates: PNF Network VNF Allotted Resource Cloud Resource Orchestration VF Module Network Note recursion VNF Allotted Resource requirement: A An Allotted Resource can be homed to an existing “underlying” network function or Service Instance, or homing could determine that a new network function Service Instance is needed. This would result in a 2 nd level of Service Orchestration. Service Y is being treated as a “Resource” from the perspective of Service X. 6 Each Resource Type has its own “Generic” model -driven flow. There currently exist such flows for “VNF” and “Network” Resource Types. Service Orchestration Resource Orchestration PNF Service Y: topology_template: node_templates: PNF Network VNF Allotted Resource capability: A Network VNF Allotted Resource

N-Level Run Time Nesting? Let The Service Providers Decide Each Service/Resource “reuse unit” results in a separate thread of orchestration. This would allow for “on demand” spin up of “lower level” (Infrastructure) Service instances. Could be extended to allow multiple “higher level Services” to each have a “share” of a “lower level Service’s” instance See next slide for an alternative modeling approach that could be used when a “higher level Service” consumes the entirety of a “lower level Service’s” instance. This alternate approach may be appropriate for a Service Provider who is concerned about the run-time complexity that can be introduced with N-Level run time recursion. 7

N-Level Run Time Nesting? Let The Service Providers Decide Service W: topology_template: node_templates: VNF_W Service_X Design Time Service X: topology_template: node_templates: VNF_X Service_Y Service Y: topology_template: node_templates: VNF_Y Service_Z For the case whereby a “higher level Service” consumes the entirety of a “lower level Service’s” instance, SDC should support the Design Time ability to construct an “upper” Service Definition from other Services definitions via substitution mapping (a. k. a. , “Compile Time Nesting”) Service Z: topology_template: node_templates: VNF_Z Substitution Mapping Distribution Time & Run Time The “lower level Services” would not be visible at Distribution Time. Hence a “flattening” of the run-time orchestration would result. 8 Service_W: topology_template: node_template: VNF_W VNF_X VNF_Y VNF_Z VNF_W VNF_X VNF_Y VNF_Z

Allotted Resources – v. PE/VRF Example 4 An instantiation request for a L 3 VPN_Cust Service would result in a VRF being instantiated. That VRF would be “homed” to an existing v. PE_Infra Service instance (i. e. , the v. PE VNF instance on which this VRF will be configured). L 3 VPN_Cust Service: topology_template: node_templates: VRF “Higher Level” Service 1 Every Resource can be exposed as a Service. The ONAP model supports this today through the “Allotted Resource” construct. This concept of “Allotted Resource” does not seem to appear in the ETSI model. Perhaps this is due to ETSI seemingly covering only instantiation of Infrastructure Services, and not instantiation of end Customer Services. 2 In this case, the v. PE VNF has been packaged as an Infrastructure Service. An instantiation request for this v. PE_Infra Service would result in a new v. PE VNF being instantiated. VRF Allotted Resource requirement: VRF_Capability “Lower Level” Service v. PE VNF 3 9 The v. PE_Infra Service exposes a capability to provide “VRFs” (a “VRF_Capability”). The L 3 VPN_Cust Service consumes this capability through its “VRF Allotted Resource” construct. v. PE_Infra Service: topology_template: node_templates: v. PE VNF v. PE_Network capability: VRF_Capability Network

Comparison with other industry work ETSI MANO: • ONAP’s separation of infrastructure resource orchestration using multi-VIM layer aligns with MANO VIM module (with added scope in ONAP to support multiple clouds) • ONAP SO (with service and resource orchestration) provides super set of functionality of ETSI MANO NFVO. • However, ONAP has broadened the MANO scope by including the following new concepts: 1) Concept of “Allotted Resource” is not discussed in MANO. 2) An “Allotted Resource” is a resource that is provided by an underlying Service, and which is allotted to a customer’s (for example) Service Instance. E. g. , a “VRF” would be modeled as an “Allotted Resource” provided by a virtual PE Router VNF. We several examples of allocated resources in 5 G (e. g. Slicing). 3) Multiple level of service nesting (ETSI MANO has only one level of nesting in Network Services). MEF LSO: • MEF’s main focus is to define standard interfaces between service provider to customers (including another service provider) • Focus is on standardizing BSS to BSS interfaces • Network Function virtualization is not main focus of MEF • Therefore, MEF’s definition of “Infrastructure” conflicts with ETSI MANO as well as ONAP’s definition of infrastructure, as cloud resources and VNF are combined into “infrastructure” 10

Conclusions • Service Providers require the ability to define Services that can be leveraged by higher order Services. • Consistent with ETSI MANO, ONAP should not separate Service Orchestration and Resource Orchestration into two separate named components, because each Resource can be exposed as a Service o What appears as a “Resource” from one Service’s perspective, may actually be a Service from another perspective. • ONAP should provide Service Providers the ability to model their “Service reuse” to drive run-time behavior on a service-by-service basis, including: o Allowing each Service/Resource level to result in a separate set of orchestration threads. o Allow the Service Provider to “flatten” some levels of reuse at run time (e. g. , through design time substitution mapping). • ONAP should provide Service Providers deployment flexibility to address scalability, geographic distribution and redundancy / resiliency o But should not impose extra complexity and cost on service providers by separating service / resource orchestration that provides little known benefit 11

Role Of Controllers in ONAP: ONAP Controllers configure and maintain the health of network services and functional elements throughout their lifecycle. • Programmable network application management platform ‒ Behavior patterns programmed via models and policies ‒ Standards based models & protocols for multi-vendor implementation ‒ Operational control, coordinated state changes across devices, source of telemetry/events, etc. • Manages the health of the network services & VNFs in its scope ‒ Policy-based optimization to meet SLAs ‒ Event-based control loop automation to solve local issues near real-time ‒ Telemetry source and action executor for outer control loop automation ‒ Self-healing and auto-scaling monitoring framework • Local source of truth ‒ Manages inventory within its scope ‒ All stages/states of lifecycle ‒ Configuration audits 12

ONAP Controller Guiding Principles: • Controllers manage the state of services & network functions (VNFs / PNFs) • There could be multiple controllers to support different technology domains – e. g. L 3 Networks, Optical networks, L 4 -7 network applications, etc. ‒ Controllers have intimate with domain specific protocols • However, all ONAP controllers must support one set of common north bound APIs (for ONAP modules, all controllers look and behave the same) • There should be functional parity amongst various controllers ‒ This is a critical requirement, otherwise SO and other ONAP module has to keep track of differences between the controllers • We must leverage common controller framework, as much as possible (reduce complexity, development and maintenance cost) ‒ All controllers have common functional modules and structure (accepting models from SDC, parsing it, north bound APIs, topology database, lifecycle management functions, etc. ) ‒ Differences are only at the VNF / PNF interface layer ‒ Leveraging common controller framework provides tremendous advantage, much smaller total code, changes are made once and leveraged by all instances, etc. • Avoid having two controllers with ONAP supporting same technology domain (e. g. L 3 Networking, Optical, IMS, etc. ) 13

Leveraging Common Controller Framework Service & Resource LCM Actions Common Controller Framework API Handler SLI Policy Engine TOSCA engine Models DGs Model Parser Common Control Functions VNF Configure Audit Rebuild Scale Network Config Stop Topology & Engineering Rules Start Heal Service Chain ODL / MDSAL Plugins/Adapters* VNFs μSvcs APIs PNFs M-VIM APIs Multi-VIM * Plugins/Adapters could include Ansible, Chef, Puppet, Netconf / Yang, CLI, SNMP, standard APIs, EMS, VNFM, etc. Personas … Note: Common controller framework is a rich collection of libraries. Each domain specific controller can include only applicable modules. 14

ONAP Controller Rationalization Opportunities: L 4 -7 Controller (App-C) Config Service Logic Life Cycle Database Interpreter Mgmt funcs Standard Adaption Layer Chef Netconf Ansible Vendor OA&M Adaptor Vendor VNFM Adaption Layer (VF-C) Life Cycle Mgmt funcs Vendor A Vendor B L 4 -7 Generic ONAP Controller API Handler SLI TOSCA engine Policy Engine Models DGs Model Parser Common Control Functions VNF Configure Audit Rebuild Scale Network Config Stop Topology & Engineering Rules Start Heal Service Chain ODL / MDSAL ? ? μSvcs APIs Plugins/Adapters* VNFs PNFs EMS VNFs PNFs s. VNFM VNFs M-VIM APIs Multi-VIM PNFs Note: Team can decide which Common controller framework libraries are applicable for L 4 -7 VNF controller. 15

Conclusions • ONAP community should create a rich library in Common Controller Framework (CCF) – This offers maximum reusability and benefits are shared amongst all ONAP members • CCF can be used to create controller instances of varying “personalities” (L 1 -3, L 4 -7, OOM, Optical, RAN, etc. ). Initially these controllers are created statically and included in ONAP Platform but the goal is to create them more dynamically by ONAP community members to meet their requirements ‒ Avoid redeveloping functionality already available in CCF ‒ Encourage community to contribute to CCF functions that be used by other controller (today or in future) • However, we should avoid multiple controllers covering same domain or family of VNFs (e. g RAN, IMS, etc. ) ‒ Provide clear & consistent guidelines to network function vendors • Each Controller must follow agreed upon architecture principles: ‒ All ONAP controllers must support one set of common north bound APIs (for ONAP modules, all controllers look and behave the same) ‒ There should be functional parity amongst various controllers • Allow operator deployment flexibility meet their unique scalability, resiliency and geographic distribution requirements • Functions which are unique or specific to a controller can be developed within a controller and can live outside CCF 16

Backup Slides

Terminology Mapping ONAP Service Orchestration Resource Orchestration Cloud Resource Orchestration Network 18 Network Service (Infrastructure Services only) (2) Network Service Orchestration (2) VNF and Network (NFVI) network resources (3) Specific NFVO functions that manage or coordinate the VNF or NFVI network resource’s lifecycle (3) NFVI compute, storage, network Functions, perhaps provided by the underlying Cloud Provider (4), that manage or coordinate the NFVI compute, storage, network resource’s lifecycle An NFVI resource Allotted Resource (5) This concept is not discussed in MANO VF Module Virtualisation Deployment Unit (VDU) VF Component Because of this, ETSI TERMINOLOGY IN AND OF ITSELF IS NOT SUFFICIENT TO DESCRIBE THE ONAP PROBLEM SPACE. ETSI MANO (1) VNFC 1) Ref: ETSI - NFV Terminology for Main Concepts in NFV 2) ONAP includes “Customer Services” that ride on top of what ETSI would call a “Network Service”. Also ETSI considers a “Network Service” as always including at least one dedicated VNF, whereas ONAP allows for “Services” that do not include any dedicated VNFs. 3) Concept of “Allotted Resource” is not discussed in MANO. The concept of “PNF” seems to be out of scope for an NFV-MANO implementation. 4) For example, the orchestration provided by Open. Stack HEAT 5) An “Allotted Resource” is a resource that is provided by an underlying Service, and which is allotted to a customer’s (for example) Service Instance. E. g. , a “VRF” would be modeled as an “Allotted Resource” provided by a virtual PE Router VNF.

A&AI Instance Representation of Prior Example Service_W Svc Instance “ 1” In this example, the entirety of VNF_W is dedicated to the Service_W Service Instance, but only a portion (represented in A&AI as Allotted. Resource_W) of the “lower level” Service_X Service Instance is dedicated to the Service_W Service Instance. This pattern repeats itself for the other Service Instances shown. VNF_W VNF Instance “ 1” Allotted. Resource_W AR Instance “ 1” Service_X Svc Instance “ 2” VNF_X VNF Instance “ 2” Allotted. Resource_X AR Instance “ 2” Service_Y Svc Instance “ 3” VNF_Y VNF Instance “ 3” Allotted. Resource_Y AR Instance “ 3” Service_Z Svc Instance “ 4” VNF_Z VNF Instance “ 4”