The need for fiber-optic transmission is rapidly expanding to cope with the ever increasing bandwidth requirement driven by new applications such as video related services and cloud applications. Fiber access infrastructure is a must in competitive environments and also a key enabler for the next-generation all-optical IP network. Bringing the optical fiber as close to the user as possible is critical for network performance and user experience. This drives fiber deployment further out in existing access networks and at the same time opens up new business opportunities to connect public buildings and enterprises.
For organizations that need major bandwidth and maximum network performance, dark fiber services provide physical security and complete control to shape every aspect of their network. Mobile network operators, enterprises and government entities increasingly turn to dark fiber as an alternative to lit services. This trend was confirmed by the discussion on dark fiber connectivity for mobile backhaul and fronthaul, taking place at last year’s Light Reading event on Backhaul Strategies for Mobile Operators in New York City. Dark fiber gives organizations more control and enables them to optimize their network performance and scalability.
Regardless of the type of the organization and the size of the business, there is an increasing reliance on the network from basic Internet access to network applications to cloud service access. Because network-based applications are becoming more important and organizations have moved mission-critical applications to the cloud, they need higher capacity and want stricter service level agreements to ensure those applications perform as desired.
Most passive fiber access service offerings – including dark fiber and wavelength services for enterprise inter-site connectivity, access to carrier points of presence and tail-end services for high-capacity long distance connectivity – are provided without active service monitoring capabilities. In comparison to lit service offerings, service level agreements are generally softer and designed with basic availability commitments. Outages caused by fiber breaks and other physical infrastructure issues can therefore not be detected proactively. This makes the customer reporting problems or outages the only trigger for corrective action. Troubleshooting is often limited to working hours, with repair time commitments constituting several hours or even days.
Service level agreements currently established for leased dark fiber services and passive optical tail-ends are no longer adequate for many applications and businesses. Increased availability and pro-active restoration are desired performance characteristics, expressed by many operations. The main reason for offering dark fiber and passive optical access services with basic performance guarantees only is not the result of having no solution. Traditional technology can provide active, in-service monitoring, however at cost points that do not support the business case. Deploying active equipment for high-capacity service termination at the service end point is often avoided, using dark fiber instead to extend the service over the last mile. Another challenge is special protocols – for example Common Primary Rate Interface (CPRI) in case of mobile fronthaul – that do not support standardized performance monitoring tools. CPRA also has service performance requirements that do not allow mapping the native data signal into common transport protocols such as MPLs or OTN. Turning to passive wavelength and dark fiber services has become the rule in this case.
Understanding this challenge and foreseeing that organizations are increasingly interested in dark fiber and passive optical access services with enhanced service level agreements, the telecommunications industry has developed new solutions to provide such services at cost points supported by the underlying business model. Recently announced optical Access Link Monitoring (ALM) technology enables fiber network operators to monitor their passive, fiber-based infrastructure and services. The new ALM technology is specifically designed for high scalability and maximum cost-efficiency, two critical factors in access network operations. Interference with the services and applications provisioned on top of the passive service is avoided by spectral separation, maintaining full transparency and providing physical security and complete control to shape every aspect of the network to the customer organization.
Applications for the revolutionary ALM technology are manifold – passive tail-ends for high-speed, long-distance connectivity services, passive fronthaul and backhaul in radio access networks, dark-fiber enterprise connectivity and many more. ALM generally supports any dark fiber and wavelength service and enables fiber network operators to offer premium dark fiber services with increased service level agreements compared their current offering. It opens up new business opportunities for increasing their top-line and profitability. What’s more, ALM technology reduces operational complexity and effort in operating fiber infrastructure. Potential issues are not only detected, they can be localized precisely to send repair teams to the exact location and restore the service quickly. Many operations with their valuable applications and services will benefit from this new technology, potentially accelerating the turn to dark fiber and passive services as an alternative to lit services.