Shock to the system

Power over Ethernet is becoming increasingly ubiquitous in the Middle East, as enterprises take advantage of the flexibility it affords them. NME looks at some of the current issues around the technology, and asks what the future holds for PoE.

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By  Eliot Beer Published  October 30, 2006

|~|khan200z.jpg|~|“You don’t need to deploy a large number of points on the UPS to cover all the different devices either, because it’s just a single solution.” Tahir Khan, systems engineer, 3Com Middle East.|~|Just as wireless networks are starting to hog the popular imagination, power over Ethernet (PoE) has been quietly revolutionising the way organisations can deploy networked devices over the last few years. Currently the most common PoE deployments use the technology to power IP telephones, simple surveillance cameras and wireless access points – the current standard supports only 15.4 watts of power. But now the Institute of Electrical and Electronic Engineers (IEEE) is currently working its way through a new standard, which promises to increase the power available to 56W. “Once 802.3at is ratified, and you have anything from 30W to 60W of power available, then a lot of devices that you can’t power today will be applicable to PoE,” says Tariq Hasan, sales support manager for Symbol Technologies Middle East. “For example laptops – that would be great, as at the moment whenever I plug in my laptop I have to plug in my power supply as well. So now if I were able to power my laptop just using my Ethernet cable, that would be very useful.” Hasan says at the moment the main uptake is for phones and wireless devices – indeed, he says a number of Symbol’s wireless products can only work with PoE. But he emphasises the critical factor of PoE as being the flexibility that it affords users; access points can now be mounted on the ceiling, rather than being (almost literally) tied to a power socket, usually located at floor level. Instead of focusing on the 802.3at standard – which is a long way from ratification – many vendors are looking at making existing products more efficient, and trying to squeeze more functionality from 15.4W. With developments around mobile technology, more and more low-consumption components are now becoming available, some of them filtering down from laptops and mobile phones. “The key message to people is not to design products which will draw a lot of power – you should design your products to use less power,” says Ivan Kraemer, regional sales and marketing director at HP ProCurve. “This is to the benefit of everybody – it’s less dangerous, less heat is dissipated. I think there is a trend for designs to use less and less power, although there are devices which do require more power – these can be catered for today by using an injected power system using third party products.” Aside from the various end devices which can use PoE, one of the main advantages of the technology is the ability to manage large numbers of devices centrally, instead of configuring each individually. This does not just extend to system management – power issues can all come under one single control panel. “It’s not just having fewer power sockets and fewer electrical lines – the manageability of the power system becomes easier, because it’s centralised,” says Tahir Khan, systems engineer at 3Com Middle East. “You don’t need to deploy a large number of points on the UPS to cover all the different devices either, because it’s just a single solution. Also, from our experience, if you put a single adaptor to each telephone or wireless access point, you’ll get more complaints about that adapter than the product itself.” But PoE does bring with it certain requirements, and certain challenges. In terms of requirements, organisations need to meet a minimum standard of cabling – for most enterprises in the Middle East this should not be an issue, but if an organisation does have older infrastructure it may be worth checking its PoE compatibility. “If you look at 802.3af, that was designed to work with Cat 3 cabling onwards,” says Zakir Lokare, enterprise business manager at Online Distribution. “If you look at the new standard, which is still in the process of being drafted, there it has to use Cat 5 onwards. Most organisations today are using Cat 5 cables, though, and the new deployments tend to be Cat 6. If you look at the current install base in the Middle East, it’s generally Cat 5 onwards – it’s not an issue for most organisations looking to implement PoE.” The main issue which has potential to cause regional enterprises headaches is the problem of heat dissipation. While PoE is still a relatively low-power technology, having a switch with 48 ports all putting out 15.4W of power – more than 700W – is going to generate some heat. Whereas before this might have been distributed around 48 different power supplies, now the heat is concentrated in the data centre. This is part of a wider issue around the increasing density of IT systems in data centres, fuelled by the rise in blade servers, multi-core processors and similar technologies. And, from the network infrastructure side, vendors are working to reduce levels of heat dissipation in PoE devices. “Dissipation rates have definitely improved over the years – if you look at the primitive ways of doing PoE, things have come a long way,” says 3Com’s Khan. “And now with vendors looking at 802.3at, they have come up with some proactive measures that can counter many of the issues around heat dissipation. But it’s not a major problem – if you look at all the insurance underwriters, they’ve done extensive tests on dissipation over cables and in data centres, and they don’t have a problem with it.” Network managers can partly avoid this problem by using intelligent planning of where PoE switches are enabled – one tactic is to distribute the switches around a building, nearer to each cluster of PoE end devices. HP ProCurve’s Kraemer says many organisations like to use power injectors in order to spread the heat over a greater area. He says there are also techniques for avoiding data centre hotspots even with integrated PoE switches. “Some of our products, where we know it’s going to be fairly loaded, with power coming out of all the ports, we would piggyback another power supply onto the switch – this can reduce the power consumption on the internal power unit, and share the load with a unit outside the switch,” says Kraemer. “But if you’re using x amount of power, you will generate x amount of heat – it’s the laws of nature, you can’t hide it anywhere. The only thing you can do is split the heat out, so you can spread the head evenly over a data centre, to avoid hotspots. But all of this has to be calculated.” Other than managing heat, one of the advantages of the 802.3af standards is that it handles negotiation with end devices automatically, so network managers do not have to manually configure each device on a PoE network. This may not be the case with power injectors, especially with out-of-standard implementations, so managers should be careful of these deployments. In the Middle East, the rise of PoE has come at the same time as the oil-fuelled economic boom; this has led to many organisations taking advantage of the technology during major infrastructure upgrades and refits. VoIP implementations in the region are steadily on the rise – virtually all of these will be powered by PoE. “I think the Middle East is what we would term a ‘tornado’ market – the uptake of PoE is absolutely incredible,” says Angus MacCormick, director of operations for advanced technologies in the Middle East and Africa at Cisco. “I think this is a combination of the economic situation, where governments are investing in education, health, infrastructure – they are rapidly deploying greenfield sites, and they’re able to refresh many legacy sites. Governments and the private sector are both looking to learn the lessons from the previous Middle East boom in the 1970s. and build sustainable economies – technologies like PoE can help with this.” One area where PoE is set to become an integral part of infrastructures is in the thousands of new developments across the Middle East. New office and business developments are an obvious area for PoE, but many observers also think the technology will come in to domestic situations as well, accompanying the rise in convergence of voice, data and now video. Aside from buildings, though, Middle Eastern enterprises are finding innovative sites in which to deploy PoE, as Dave Hughes, technical support manager Middle East at Panduit explains: “The first PoE panel we ever deployed in the Middle East was on a ship – it was still running was wireless access points and cameras, but we hadn’t really thought of installing it on a ship before. I think it’s the environments that these things that these things can go into are what makes it so flexible. “As technology is evolving and new applications are coming through – such as intelligent buildings – enterprises are seeing PoE as something that can be easily retrofitted into existing systems,” he adds. Looking to the future of PoE, the technology is in many ways at a turning point. There is increasing pressure for vendors to deliver more power over the cables, but as with similar situations – such as wireless 802.11n pre-standard products – there is a risk that by releasing early versions of 802.3at systems, vendors may find themselves with incompatible product lines – leading to end users with obsolete systems or vendor lock-in. At the same time, companies like cabling vendor Reichle & De Massari (R&M) are developing – and selling – proprietary systems to deliver higher wattage power over a single cable. R&M’s RCC45 system, which carries two additional 1mm2 cores in addition to the normal UTP Ethernet cable, allows the delivery of around 200W of power – enough to run large-screen displays and full pan-and-tilt surveillance cameras, among other devices. Technically, there are fundamental physical issues with how much power can be delivered down the slender AWG 24 cores in a standard Cat 5 cable. One way round this is to utilise all four pairs of cores in the cable to deliver power, instead of just the unused pairs at present. This brings its own challenges, but vendors are confident they will be able to solve the technical issues, and start to deliver some very interesting services in years to come. “What’s interesting is to imagine digital cities, where wireless mobile access is ubiquitous,” speculates Cisco’s MacCormick. “You’re going to need to deploy wireless base stations to do this, and with PoE you can put them everywhere, with just one cable – even rugged versions for outdoors. "Potentially, in the future, you can also look at video surveillance cameras as well – this is where I think it’s going in the next two to three years. For operators, this is going to reduce their costs, reducing the infrastructure they have to deploy, and also allow them to deliver new services.” ||**||

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