Talking to the audience of data centre professionals at the event, which is held in conjunction with the Data Centre Alliance and the Faculty of Engineering of the University of Leeds, Benn discussed the latest challenges in data centre networking and offered guidance on approaches to support future needs.
Tony Benn opened his talk with an acknowledgement that the data centre environment is ever evolving, not only in terms of ever increasing speed and storage, but also in development of delivery methods. He summarised the options available today; 10GBase-T, 40GBase-SR4, 100GBase-SR10, plus detailed the new protocols being developed: 32Gbp and 128Gbp Fibre Channel, plus 40 and 25GBase-T on copper.
With these current and future options outlined, Benn went on to ask the audience of industry professionals whether they considered their own infrastructure capable of supporting future needs and applications. Speculating on a likely answer, he suggested for fibre it might be a ‘no’, as networks have typically been designed around 10Gbps and a 2.6dB insertion loss channel limit.
However, for 40Gbps over copper, Benn expected the response of ‘probably not’ and hypothesised that new applications will potentially need new infrastructure, or at least a revised layout as this next generation application is intended to operate over a two-connector channel up to 30m. He asserted that this is worthy of immediate consideration, with 40GBase-T and 25GBase-T under development by the IEEE 802.3bq task force, with a target date of February 2016 and both TIA and ISO having Category 8 under development, with a target date of quarter four this year.
For fibre, Benn spent time highlighting the need to calculate maximum losses in a channel when considering 10GBase-SR4 and above, rather than just typical losses. He summarised the maximum loss budgets and lengths for various standards and presented examples to demonstrate the requirement for low loss vs standard loss solutions. One warning he offered for MPO/MTP solutions was to include the losses on each side of a module, rather than the published loss figures for a total module. Building on this point, Benn also stressed the importance of factoring in the trunk and jumper losses into the total, ensuring that all components used in the channel are taken into account.
‘Density with clarity’ was a key theme in Benn’s presentation: He described the challenge of maintaining port level clarity in ultra dense environments, which are increasingly common as needs expand, whilst real estate remains at a premium. Selecting products based on their functionality at maximum density was his encouragement to the audience.
Finally, Benn concluded with a case for an end of row (EoR) or middle of row (MoR) zoned topology as opposed to a top of rack (ToR) design for the data centre infrastructure. A zoned topology, he said, affords modularity, flexibility, reduces unused ports and saves on access switches and related power and cooling, licensing, maintenance and space costs. A zoned approach also saves on fibre optic uplinks to aggregation or core switches and allows for easy updates during moves, adds and changes.