New advancements in software-defined control and network automation are enabling optical service delivery transformation. Stitching together network connectivity across vendor-specific domains is labor-intensive; now those manual processes can be automated with emerging solutions like multi-vendor optical domain control and end-to-end service orchestration. These new solutions provide centralized service control and management that are capable of reducing operational costs and errors, as well as speeding up service delivery times. While this sounds good, it can be all too easy to gloss over the complexities of decades-old optical connectivity services. In this blog post, I will explore the four enabling technologies for multi-domain optical service delivery as I see it.
The first enabler, optical service orchestration (OSO), is detailed here. In the not so distant past, most carriers deployed their wireline systems using a single vendor’s equipment in metro, core, and regional network segments. In some cases, optical overlay domains were deployed to mitigate supply variables and ensure competitive costs. While this maximized network performance, it also created siloed networks with proprietary management systems. The OSO solution that I imagine effectively becomes a controller of controllers, abstracting the complexities of the optical domain and providing the ability to connect and monitor the inputs/outputs to deliver services. As such, an OSO solution controls any vendor’s optical domain as a device, with the domain controller routing and managing the services lifecycle between vendor-specific end-points.
The second enabler is an open line system (OLS) consisting of multi-vendor ROADMs and amplifiers deployed in a best-fit mesh configuration. A network configured this way must be tested for alien wavelength support, which means defining the domain characteristics and doing mixed 3rd party optics performance testing. This testing requires considerable effort, and service operators often expect complete testing before deployment. The question is, who takes on the burden of testing in a multi-vendor network? Testing is a massive undertaking and operators do not have the budget or expertise; perhaps interoperability labs at MEF and CE services could help define it. Bottom line, there is no free lunch.
The third enabler is a real-time network design for the deployed network. Service operators deploy optical systems with 95%+ coverage of the network and are historically limited to vendor-specific designs. Currently, the design process requires offline tools and calculations by PhDs. A real-time network design tool that employs artificial intelligence algorithms promises to make real-time network design a reality. Longitudinal network knowledge combined with network control and path computation can examine the performance of optical line systems and work with the controller to optimize system design, variations in optical components, types, and quantity of fiber optical signals, component compatibility, fiber media properties, and system aging.
The final enablers are open controller APIs and network device models that support faster and flexible allocation of network resources to meet service demands. Open device models (IETF, OpenConfig, etc.) deliver common control for device-rich functionalities that support network abstraction. This helps service operators deliver operational efficiencies, on-boards new equipment faster, and provides the extensible framework for revenue-producing services in new areas, such as 5G and IoT applications.
Controller APIs enable standardized service lifecycle management in a multi-domain environment. Transport Application Programming Interface (T-API), a specification developed by the Open Networking Foundation (ONF), is an example of an open API specific to optical connectivity services. T-API provides a standard northbound interface for SDN control of transport gear, and supports real-time network planning, design, and responsive automation. This improves the availability and agility of high-level technology independent services, in addition to specific technology and policy-specific services. T-API can seamlessly connect the T-API client, like a carrier’s orchestration platform or a customer’s application, to the transport network domain controller. Some of the unique benefits of T-API include:
- Unified domain control using a technology-agnostic framework based on abstracted information models. Unified control allows the carrier to deploy SDN broadly across equipment from different vendors, with different vintages, integrating both greenfield and brownfield environments.
- Maintaining telecom management models that are familiar to telecom equipment vendors and network operations staff, making its adoption easier and reducing disruption of network operations.
- Faster feature validation and incorporation into vendor and carrier software and equipment using a combination of standard specification development and open source software development.
Service operators are looking for transformation solutions with a visible path to implementation, and many solutions fall far short and are not economically viable. Fujitsu is actively co-creating with service operators and other vendors to integrate these four enabling technologies into mainstream, production deployments. Delivering ubiquitous, fully automated optical service connectivity management in a multi-vendor domain environment is finally within reach.