WideCap multimode fibre delivers OM4 performance at 850-950nm while maintaining compatibility with current multimode fibres. Traditional OM4 fibres offer high bandwidth in a narrow band around 850nm. WideCap and multi-wavelength transceivers are a viable solution for future 100, 200 and 400Gb/s systems.
Cost and energy efficient 100Gb/s solution over one WideCap MMF
To support the exponential growth of data traffic and cloud services, cost effective and large-scale installation of Data Centre transmission rates, extend reach and preferably maintain duplex connectivity.
“Transmission through multimode fibre with VCSELs has been considered as the lowest cost and power efficient solution for short-reach links in data centre networks operating at 10Gb/s. However, as line rates increase, the capacity of MMF links is limited by the spectral characteristics of VCSELs and dispersion OM4 fibres. To solve this limitation, parallel systems using multiple fibres have been used to reach higher speeds (40 and 100Gb/s). The recent 100GBASE-SR4 Ethernet standard specifies reach of 100 m using four parallel OM4 fibres and MPO connectivity. The need to achieve higher capacity could easily be achieved through the utilization of additional parallel fibres. However, this solution becomes less practical as the number of fibres increases, making the cable plant management complex. WDM and Wideband MMF is seen as a viable solution to extend the benefits of MMF and VCSELs systems to speeds higher than 25Gb/s, while using duplex LC connectivity” explains Adrian Amezcua Correa, MMF Product Line Manager, at Prysmian Group. “In the near future, WideBand MMFs and WMD technology is expected to capture a significant market share in data centre networks. A single WideCap MMF offers four times higher capacity than OM4. With WideCap and WDM transceivers data centre networks can operate at 100Gb/s, bridge considerable distances over one fibre.”
“Prysmian had been working on this type of solution before. Initially, we were focusing exclusively on boosting modal bandwidth. In 2013, R&D Scientist Denis Molin, Marianne Bigot and myself got involved in further increasing the spectrum of multimode fibres. At the beginning of 2014, we started looking at a new approach: combining chromatic dispersion with modal bandwidth to arrive at a higher total bandwidth with the performance needed to achieve at least four WDM channels at 25Gb/s over 100m. The total bandwidth of a multimode fibre is a combination of chromatic dispersion and modal, and by optimising fibre’s modal bandwidth, the team managed to develop WideCap. Our first publication on WideCap was at the ECOC conference in Cannes in September 2014, one week later the Telecommunications Industry Association (TIA) group created a working group to define a WideBand MMF standard, this showed the great interest of the industry in this new fibre. Now the work in TIA is almost completed, and we can say that WideCap has set up a new standard in MMF technology.”
Optimum wavelength range
“When we started, we first had to identify the optimum operational range. We discussed this with different parties in the ecosystem and decided that 950nm wavelength would be a good balance between fibre and VCSEL characteristics, to achieve 100 Gb/s transmission. WideCap incorporates BendBright® technology to withstand tight bends and cabling challenges in data centre networks. You can smaller, high-density fibre management systems in tight spaces, whilst improving overall network reliability.”
“In DCs, where 10G has been the standard for some time, there was no need to use parallel fibres for long distances. But with the introduction of higher-bandwidth solutions, you do need parallel fibres. We now offer this without the need to use multi-fibre connectors, and also consuming less power.”
WideCap complies with or exceeds IEC 60793-2-10 type A1a.3 Optical Fibre Specification, ISO/IEC 11801 OM4 specification, TIA/EIA-492AAAD detail specification and Telcordia GR-20-CORE and GR-409-CORE specifications.