Electrical Contracting News (ECN) December 2016 - Page 40

SPECIAL FEATURE DATA CABLING GAINING ADVANTAGE Joergen Janson of Corning explains how power budgets can be conserved as data centres grow. E lectrical contractors working in data centres are all too aware of the need to minimise power consumption and accommodate efficiency measures to eliminate energy waste. The data centre is the linchpin of the IT infrastructure within an organisation, and it consumes a lot of power. Densely concentrated electronics produce excess heat that, in turn, necessitates cooling. The general rule of thumb is that for every 1W of electricity to power the data centre IT infrastructure, another 1W is typically required to maintain a safe temperature range. This power load has further knockon requirements for sizing expensive UPS and power protection, which must be specified to match the total required kVA rating to ensure continual operations in the event of a main outage. It is not surprising that most large organisations aspiring to reach environmentally sustainable corporate social responsibility targets, as well as to minimise running costs, place significant scrutiny upon their data centre investments. Unfortunately, this tactic is made far more challenging given the exponential rate of IT data growth that drives the need for ever faster, denser, and more powerful data centre facilities. High performance data centres in 2016 commonly utilise fibre optic cabling for interconnectivity between the various racks and cabinets full of IT hardware. Without this cabling, data centres would be effectively useless. Optical cabling consumes less power and produces less heat than the copper based cabling infrastructures it has replaced, and is able to attain larger data transmission over longer distances. These attributes are essential to support the enormous amounts of data that organisations need to transport in increasing quantities within their data centre environments. Gigabit Ethernet switches Among the most mission critical and sensitive components of the data centre communications infrastructure are the latest generation of Gigabit Ethernet switches. Transceivers within this equipment follow industry standard protocols to enable capacity of 40GBps (or G) and even 100G. Many organisations are expected to implement these technologies as they migrate to ever faster communications, typically from a current level of 10G. The problem with migrating to these systems is the disruption and cost associated with connecting up 40G interfaces using the existing 10G centric cabling infrastructure. Organisations face the prospect of having to consume huge amounts of power to achieve the performance they require. Take the example of an organisation deploying three fully loaded switch chassis, each with the standard eight racks of 48 x 10G ports. That’s a total of 384 x 10G ports per switch, and 1,152 ports overall. Each of the 1,152 ports requires 1W to power it s transceiver, while the switches themselves, their 24 x 48 port line cards, and additional accessories will consume even more. Double this power load to accommodate the commensurate cooling requirement and a conservative estimate would be well in excess of 2.3kW. Denser footprint The latest generation of switches can use 40G ports in a denser footprint to transmit the same amount of data. On a single switch chassis, eight line cards with 36 x 40G ports on each equates to 288 x 40G ‘The latest generation of switches can use 40G ports in a denser footprint to transmit the same amount of data.’ in total – the same as the 1,152 x 10G in the example above. 40G port transceivers each require 1.5W of power, and there are fewer additional components than in the 10G model. Even when you double the load to take account of cooling, the total is little more than 0.8kW. So how can you transition to the 40G based system while still using the 10G cabling infrastructure? Corning’s Edge8 solution port breakout modules deaggregate each 40G port into four 10G ports. While this requires an additional cabinet of room within the data centre, the net effect is a reduction in overall space compared to the three cabinet equivalent. And because the port break-out housings are entirely passive, they require no power, no cooling, and no UPS back up. Private organisations with their own on-premises data centres are already benefiting from this innovation as part of their 40G migrations. But not everyone consumes data centre facilities in this way. A significant portion choose to outsource all or some of their data centre assets to colocation providers. For years, data centre colocation providers have charged out their environments to customers according to space occupied and/or data transmitted. However, the status quo appears to be changing as a few prominent providers begin to transition to new cost models based on energy consumed. This is more than just another commercial disincentive to avoid waste. Electrical contractors with a good understanding of how to reduce power load while increasing data throughput will be at a competitive advantage. 40 | December 2016 40 Data Cabling – Corning.indd 40 11/11/2016 16:42