Comms Supplemnt: Cabling - Exacting demands
Written by Philip Hunter
A good cabling solution can 'sweat' an existing data centre or squeeze every last bit of investment out of a new build ensuring you get the best out of your telco and data communications architecture. Philip Hunter investigates what is the best cabling design, port options and mix of fibre and copper to use in reducing data centre heat, while maximising latency and efficiency
Performance usually presides over economics in decisions about cabling in the financial services sector, but this truism was temporarily reversed during the credit crunch when many IT budgets were slashed or frozen. Now it is all change again, with renewed interest in advanced cabling systems to cope with the predicted growth in data traffic and storage requirements over the next few years as the economy picks up and new regulations hit. In fact economic and performance factors are conspiring to drive a new wave of investment in cabling systems, according to Alastair Waite, European, Middle-East and African (EMEA) head of enterprise product management at ADC Krone.
"There was a significant downturn from October 2008 until towards the end of 2009," says Waite. "But this year we have seen increasing activity in the financial sector driven by the consolidation of data centres to improve efficiency, and geographic expansion to build revenues. This, in turn, has driven demand for cabling to cope with the increased volume of data being managed and transferred." The trend is especially prevalent in the wholesale banking segment where speed and capacity are vital to cope with automated algorithmic systems. Retail banks too though have seen the demand for data rise as more customer data is kept for cross-sell opportunities or regulatory purposes.
It has tilted the balance of power back towards more expensive fibre systems, at least in the data centre. "The driving factor behind fibre uptake in the financial sector is an increased requirement for performance and storage as companies attempt to capture and store an ever increasing amount of business critical information," notes Ewan Wilson, managing director of HellermannTyton Data, a UK-based maker of structured cabling products.
Copper is still holding up in the workgroup, where its current performance of up to 1 gigabit per second (Gbps) is more than adequate for most if not all current trading floor and other local area network (LAN)-based applications. "Your HR or compliance department isn't likely to need 10 gigabit Ethernet (GigE) coming out of wall outlets in the foreseeable future," wryly notes Remco van Mook, senior technical architect for Europe at Equinix, a provider of managed data centres, for instance in the stock exchanges arena, where high performance and reliability of cabling is crucial. There is still a place for copper in the data centre, he argues, but it must be a high performance shielded grade. "For data centre deployments, using a higher grade copper cable means less sensitivity to outside interference, alien cross-talk, performance impairments and the like, which does tend to add up if you've got hundreds of cables going in the same direction."
To remain competitive in the data centre and also provide an eventual upgrade path from 1 GigE in the workgroup, the 10 GigE version of copper, called 10GBASE-T, must become more affordable and much less power hungry. "10GBASE-T has been in a bit of a holding pattern, waiting on the power requirements of the chips to reach acceptable levels," explains Carrie Higbie, global director for data centre solutions and services at Siemon, a worldwide manufacturer of IT cabling systems. "This is very similar to when gigabit Ethernet first came out. The first generation chips there were 6.5W per port and now are less than a watt in most cases. The new 10GBASE-T chips now in mass production are around 2.5 to 3.5 watts per port, depending on the length of the channel."
Higbie also notes a drive towards shielded systems. This is backed up by a recent survey by BSRIA, a building services research company, which revealed that in the US, where unshielded systems have been predominant until recently, 75 per cent of all data centres adopting 10GBASE-T were using shielded cabling systems.
There is a strengthening trend towards distinct cabling systems for the data centre and the workgroup LANs surrounding it. This extends not just to the cabling system itself but to the overall strategy, which should be more short-term for the data centre where performance is that much more critical, according to Equinix's van Mook. "It's very feasible to engineer your access layer to last 10 to 15 years, keeping two future upgrades of hardware in mind," he says. "In the data centre however, it's hard to predict what the future will hold even five years from now, so keeping your options open with scalable installations is, in my opinion, best practice."
Some future-proofing of cabling systems is still a good idea, but it pays not to try and look too far ahead. There are contrasting views on this, often depending upon whether the data centre or workgroup perspective is paramount at a given firm. "Over specification has always been seen to be much less of a risk than losing a competitive edge to the competition," argues ADC Krone's Waite, making the point that it is a false economy to install a system that may soon run out of steam in a sector where loss of IT service is very costly.
On the other hand it is throwing money away to invest too much in a system in the hope it will continue to meet performance requirements, say a decade away. "Over-specifying a system is a genuine gamble," reckons Ken Hodge, R&D manager at Brand-Rex, a supplier of structured cabling systems. "Presuming the next unknown protocol that appears will fit into the available envelope of that system is a risk not worth taking." Instead, Hodge contends that financial institutions should only consider cabling systems within the context of existing standardisation and roadmaps, rather than trying to pre-empt the future. Working beyond the foreseeable future of these roadmaps is not recommended in his opinion.
Evidence for this viewpoint can be found from both past fibre and copper systems. "People who invested heavily in fibre in anticipation of 40/100 Gbps standards will likely be disappointed to find out that even though the fibres will be used, the connectors and even the number of fibres required per connection will be different from what they've installed," says Equinix's van Mook. Some early adopters of the Cat6 Unshielded Twisted Pair (UTP) have had similar experiences."
Cat6 UTP was thought to be future proofed when it was introduced but it turned out not to have sufficient bandwidth to run the new 10GBASE-T application, which when it came along was found to need 500MHz and so Cat 6A had to be developed.
It can be argued that for both fibre and copper, it is now possible to future proof at least the physical cabling for a longer period by selecting grades known to have the greatest leg room. This means a single mode system in the case of fibre and a shielded system for copper. In both cases this ensures much higher potential performance. Single mode fibre is narrower and carries just one ray of light, with much less dispersion of the radiation, allowing the signal to operate at higher frequencies and therefore carry more data. Shielded copper is less susceptible to electromagnetic interference, which has the same effect of allowing higher operating frequencies. Therefore adoption of either will definitely provide more head room for future increases in performance, but the electronic components and connectors installed with the systems could still become obsolete.
An overhaul could well be needed when Ethernet moves up to its next projected performance level, probably 40 Gbps. "There is talk of 40GBASE-T being a potential future project in the cabling standards application committees and it is being suggested in some quarters that Cat7A (shielded) might support it," says Brand-Rex's Hodge. "But this is nothing more than a hope at the moment. No-one yet knows what bandwidth or connector types will be required for that technology and there is no certainty that existing Cat 7A offerings will be adequate. In fact we don't even know yet if the project will start."
Power and IIM concerns
Among other key considerations is power consumption, with the Energy Efficient Ethernet (EEE) standard increasingly gaining traction. This will have an impact on the choice of cabling system installed by financial institutions in the future because EEE sends data in short fast bursts to save power. It will therefore need higher speed network connections. Your communication architecture will need to be wired to cope.
Along a similar vein there is revival of interest in Intelligent Infrastructure Management (IIM) tools to cut costs and save energy. "Being able to switch off parts of the infrastructure that are not in use is a very good way of optimising power consumption inside a data centre and ultimately saving money," says Equinix's van Mook. "But the data communications links themselves should never be shut down. Typically you'd want to use the network infrastructure for remote management to switch other equipment on or off, so it doesn't really make sense to consider switching that off as well - you lose visibility."
On a trading floor IIM has the potential to maximise availability and avoid heavy losses associated with even small amounts of downtime. "A company has the ability to detect when a cable has been disconnected, which can save billions if the cable connects an algorithmic trading line," explains Siemon's Higbie, painting a terrifying picture for investment firms that have to rely on latency and 100 per cent reliability, via instant backup systems. Business continuity is vital to these financial market participants so being able to check on the health of a cabling and communications architecture is probably worth the investment required. Whether it is best practice for smaller domestic firms or banks is debatable but each case must be judges on its merits.
In conclusion it is a false economy to cut corners now that an economic upturn is hopefully on the way, but it is a true economy to avoid spending too much insuring against presumed future increases in demand for performance and bandwidth. The middle road of not over specifying or under investing remains the best option for meeting the exacting cabling demands of data centres in the financial services sector. Regular audits to advise when upgrades might be necessary would also be good practice.
• For some examples of cabling systems installed at financial institution facilities please see our FST Awards website, data centre category (http://www.fstech.co.uk/awards). The Fidelity project from 2010 and last year's NAG entry both used high performance cabling systems to deliver state-of-the-art centres.