Optimising broadband internet connections The EU-funded INSPACE project uses Space Division Multiplexing technology to create a sustainable broadband connection. Digital Economy © hywards, Shutterstock The internet and broadband applications that we all use on a daily basis via our connected devices require huge amounts of bandwidth. The associated broadband traffic, especially for video-based applications, increases with an annual growth rate of more than 50 %. If society wants to keep pace with such developments, it must continuously upgrade the capacity of its backbone broadband networks in a way that is both scalable and cost effective. Using Space Division Multiplexing (SDM) technology, the INSPACE project is ensuring the sustainability of today’s broadband internet based society. ‘Our objective was to develop innovative networking solutions that offer network capacity scalability beyond what current solutions offer and in a cost-efficient and power-effective way,’ says Project Technical Manager Ioannis Tomkos. ‘What we achieved were significant conceptual and technological advancements in the area of optical networking, many of which are now being used by renowned research groups around the world.’ Core fields of development The project focused on three core fields of development. First was the implementation of an advanced software-defined and controlled high-throughput network node. This in turn required project researchers to first design and develop new hardware that could simultaneously handle the network traffic coming from multiple network directions and fibre links. Second, the project developed new optical fibre transmission models and impairment mitigation solutions. ‘This ensured that we could achieve excellent system performance and signal transmission over very long distances, as is required in core networks,’ explains Tomkos. Last but not least, the project developed algorithms for optimising network resources. These algorithms have built-in control plane extensions to efficiently support the effective handling of all available resources in the optical frequency/wavelength (i.e. multiple wavelengths/frequency slots) and space (i.e. multiple fibres) dimensions. A competitive edge Working on these aspects put INSPACE researchers at the forefront of the Optical Networking field of SDM – a topic that was in its infancy at the time the project first launched. ‘Over the duration of the project, INSPACE was in fierce competition with other major research programmes happening around the world, including Japan and the US,’ says Tomkos. However, it was the project’s unique addition of spectrally-flexible optical networking concepts to the SDM approach that gave INSPACE the edge. ‘We accomplished this by implementing the so-called spatial integration of optical network elements for a spectrally-flexible optical network based on super-channels,’ explains Tomkos. ‘We did this in a way that their use can be shared for multiple parallel WDM systems running over multiple spatial dimensions, thus creating the potential for huge capacity scaling and cost-per-bit reduction through optical fibres/components integration and sharing.’ According to Tomkos, the entire optical communications/networking scientific community anticipates that SDM, in combination with spectrally flexible optical network solutions (i.e. what INSPACE touts as “Spatially-Spectrally Flexible Optical Networking”: SS-FON), will become the key solution to the looming capacity crunch. Keywords INSPACE, broadband, internet, SDM, fire safety, optical communications
