Networks Europe Issue 19 January/February 2019 - Page 28

28 NETWORKING Transceiver Shipments of 25 Gb/s and Greater Current vs Future Network Configurations Enterprise data centre network migration Current enterprise data centres primarily use 10Gb/s switches and 1Gb/s servers. These networks are migrating to 25 or 40Gb/s uplinks and 1Gb/s servers. The majority of enterprise data centres already have multimode cabling installed, and 85% of these optic links are 150m long or less. The migration path for enterprise data centres, as seen in Figure 2, will take advantage of existing multimode cabling while moving to 10, 40, and 100Gb/s in the future. With over 12 different 40Gb/s transceiver options and 10 different 100Gb/s transceiver options available on the market, infrastructure engineers must design their networks to be flexible and able to support any of these potential designs. Cloud provider network migration Cloud networks have operated at 40Gb/s uplinks and10 Gb/s at the server for several years. These networks will move to 100Gb/s uplinks and 25Gb/s at the server in the near future, as shown in Figure 2. We can also expect future migrations to 200 and 400Gb/s uplinks and 50 and 100Gb/s at the server. When comparing optical fibre systems for these higher speeds, cloud service providers are increasingly adopting single-mode over multimode systems. In 2016, Microsoft Azure, a market leader in cloud services, moved the vast majority of its data centre fibre cabling to single-mode. In fact, Microsoft is now 99% single-mode, using parallel single-mode with MTP connections more than any other fibre type. Also, Facebook has undergone efforts to shorten their data centre cable links to 500m or less. Actions like these from companies with such major purchasing power have reduced the cost of single-mode optics to the point where the cost for 100 Gb/s single-mode optics dropped tenfold over the past two years, bringing it in line with multimode fibre. As this trend continues, the market, in general, will find single-mode a more enticing option. For example, 100G-PSM4 single-mode technology, created in 2014 by a multi-source agreement group, is currently the same price as 100G-SR4 multimode transceivers. PSM4 transceivers were specifically designed as a low-cost option for 500 metres or less, using an 8-fibre MPO/MTP connection. Just as important, the price for long-reach single-mode solutions such as 100G-LR4 has dropped and will continue to drop in the coming years. Smart migration Regardless of the type or size of the data centre, IT managers are looking for cabling systems that can weather multiple generations of tech upgrades with minimal disruption, dark fibres or changes. It’s recommended to use a 24-fibre trunk cable backbone in these systems as a key piece in establishing the most flexibility when migrating to 400G. Some single and multimode cabling systems not only meet current bandwidth requirements, but also provide the flexibility needed to meet future network demands, including 100G, 400G, and beyond. These systems include high-density patching, solutions for fast deployment, and customisable trunks and cable assemblies that give data centre managers the exact solution they require and to deliver it fast. n