Provisioning of optical wave services for wholesale and enterprise customers has been a highly challenging and time-consuming task for communications service providers (CSPs). It requires complex integration and configuration across access, aggregation and core nodes, in a multi-domain, multi-vendor network with various inter-carrier agreements.
The traditional architecture for provisioning (shown below) lacks a unified view of resource availability (for example, network node, capacity, port availability, bandwidth, etc.) because the network domains function in silos. This causes significant delays in communication and approvals at each touchpoint and negatively impacts provisioning.
Traditional network architecture
The current service provisioning process requires a lot of manual intervention, which makes it complex and time-consuming. Provisioning an optical wave service to enterprises, for example, typically takes about 45 days. Improving the process requires reconciling resource inventory. Using software-defined network multi-domain orchestration (SDN-MDO) can give CSPs a unified view of network resources across domains.
Achieving zero-touch provisioning
MDO can help CSPs achieve dynamic and real-time provisioning of services by configuring core and edge nodes with a federated view of resources. It simplifies end-to-end creation, provisioning and deployment of services across multiple domains, thus becoming a key element in next-gen networking. One of the key differentiators is MDO’s ability to create service function chains across virtual and physical network functions.
Key MDO enablers
Resource adapters (RAs) and traffic engineering refinement (TER) are key enablers of a comprehensive MDO architecture. They work together to create a unified view and control of the network infrastructure, which increases efficiency.
RAs are software plug-ins designed to enable seamless integration/onboarding of multi-vendor domains to the SDN-MDO. They help provide a consolidated view of core and edge network elements.
Effective TER methodology enables dynamic inter-domain provisioning of network paths/routes. TER also helps with provisioning and configuration of network services based on:
- Optimum path selection (minimum latency and hops)
- Policy-based configuration in abstracted IP and optical networks
- Path across multi-network vendors
- Global view of networks and network elements
- Programmable network processors
- Traffic grooming methodology like classifier, mapper, label etc.
- Optimized nodes/elements
- Provisioning based on constraints like the quality of service, class of service, quality of experience, jitter, etc.
Two major components of TER are the path computation engine (PCE) and provider edge-to-provider edge (PE-to-PE) configuration engine.
- PCE is a functional component or application in an abstract architecture that determines the path through which a network operates in a topology map (traffic engineering database).
- In an SDN/NFV ecosystem, PCE is an integral component that enables inter-domain provisioning of network paths/routes.
- PCE determines the flow of traffic within a domain.
- The provider edge network plays a significant role: The PE router imposes a unique label on the traffic source and forwards it to the core network; it becomes the interface for various client traffic types.
- In order to enable dynamic provisioning and activation of network services, the SDN controller layer triggers the routing and forwards the information to the core network.
- PE-to-PE configuration makes the edge network programmable and adaptable to varying customer needs.
Business benefits of SDN-MDO
To sum it up, SDN-MDO delivers many potential benefits to CSPs:
- Real-time provisioning – An SDN orchestrator with an effective TER implementation reduces the order-quote-provision cycle from about 45 days to just a few minutes.
- Interoperability – SDN-enabled domain controllers establish seamless interoperability among heterogeneous networks, which in turn helps in rapid provisioning of services.
- Customer experience – Using an SDN orchestrator in conjunction with analytics interacts with customer business intelligence systems to enhance customer experience metrics.
- Time to market – MDO enables refined traffic for faster provisioning across layers and domains, thus reducing the order-to-activation cycle.