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02/12/2017

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What the Windows hordes won’t offer is the MacBook Air’s impressive battery life. Last year’s MacBook Air lasted for 4.5 hours when running the intensive PCMark 8 tests non-stop, but the improved power-efficiency of the Broadwell chip increases that to 7 hours 15 minutes. It also delivered a stonking 11 hours 20 minutes of streaming video on the BBC iPlayer, which suggests that there’s still some mileage left in this ageing design – as long as you don’t mind that low-res screen.To be fair, the battery life of the MacBook Air is still hard to beat, and a more mass-market price tag would probably see the darn thing flying off the shelves again. But the bottom line is that it’s now an entry-level laptop with a mid-range price tag.Apple justifies its premium prices by delivering premium design, and on that score the MacBook Air, sadly, just doesn’t cut it anymore, but at least it has a choice of USB and Thunderbolt interfacing as standard. Review Last year’s update to the MacBook Pro was more notable for its £100 price cut than the modest speed bump that accompanied it. However, this year’s model is a more interesting kettle of fish, as it introduces Intel’s latest Broadwell processors to the Mac range, along with Apple’s new Force Touch trackpad doohickey.

The caveat here is that it’s only the 13-inch version of the MacBook Pro that gets the next-gen makeover. The 15-inch model has been overlooked for the time being, so if you want to get all touchy-feely with the new trackpad then this 13-inch model – and, of course, the shiny new 12-inch MacBook – are your only options for now.The Force Touch trackpad is the only outward sign of change in this year’s 13-inch MacBook Pro. The new device does away with old-fashioned buttons and moving parts, and the surface of the trackpad now sits on top of four sensors that can precisely measure the pressure that you apply with your fingers.You can still use the trackpad in the traditional manner to perform single or double-click actions, but the precision of the trackpad’s sensors allows it to introduce a third option that Apple calls the "force-click".To force-click on an item, you simply click on it once as normal, but then maintain the pressure with your finger until you feel a second click. This force-click can be used to perform actions such as increasing the speed of video playback by increasing the pressure that you apply to the Forward or Back buttons. You can force-click on an address to quickly look it up on a map, or force-click on a file to get a Quick Look preview.

The latter option reveals the sensitivity of the sensors, as you can control the speed with which the preview image zooms up from thumbnail icon to full-size preview by slowly increasing the pressure with your finger. The trackpad preferences panel allows you to adjust the pressure sensitivity, or you can simply turn the force-click option off altogether if you prefer to stick with the conventional single and double-click options.To be honest, those particular force-click examples didn’t really strike me as particularly innovative or useful. But, after spending some time randomly force-clicking everything in sight, I did discover that force-clicking on web links or search results gave me a preview of the web page on the other end of the link.

Viewing search results this way was something that I found quite useful, but it’s hardly revolutionary, so maybe it’ll take some time for Apple to come up with a more useful application for this new touch-tech.Let’s break down the different types of fibre-optic cables. In common with copper, not all fibre-optics are created equal. There are differences in their distances and indoor/outdoor use ratings, and there are consequently two main types of fibre-optic: Multi-Mode Fibre – MMF (OM1, OM2, OM3, OM4) – and Single-Mode Fibre, or SMF (OS1).The difference between SMF and MMF is that with SMF, the light follows a single path through the fibre, while MMF uses multiple paths. The SMF has a narrow core of 8.3µm compared to MMF's 50 or 62.5 µm. SMF requires more precise termination and connection. Both SMF and MMF come in two wavelengths, 850nm and 1300nm, with the latter supporting longer distances. Typically SMF cables are yellow, MMF cables are orange, and OM1, OM2, OM3 and OM4 are aqua. OM4 is also coloured violet by some vendors.

MMF fibre is easier to install and costs less than SMF, but MMF is used for short distances of less than 300m, compared with SMF, which can be used for distances of up to 6.4 miles (10km). That distance is the standard maximum, however distances greater than 80km are possible if all the right pieces – the transceivers and the buffers – are perfectly aligned.New cabling of both types now has enhanced bending sensitivity, allowing for greater use in tight bends with minimal signal loss.10GBASE-SR: The most commonly used fibre-optic cabling for 10GbE is the 10GBASE-SR cable. The 10GBASE-SR is a MMF, short-reach cable that supports an SFP+ connector with an optical transceiver. Due to its lower cost and lowest power, 10GBASE-SR is a popular fibre-optic choice. The OM3 and OM4 are both laser-optimized MMF fiber that were designed for faster networks such as the 40G/100G Ethernet standard that was published by IEEE in 2010.10GBASE-LR: These are long-reach fibre-optic cables that support single-mode fibre and connectors. They are intended to be used over long distances, such as connecting data centre to data centre. However given that cost of OS1 fibre has come down in recent years, SMF is used as the fibre of choice for runs between floors of building.

10GBASE-LRM, 10GBASE-ER, 10GBASE-ZR: These are other long-reach and extended-reach fiber, and are not discussed here because they are not “common” types.Now you’ve got your cables, what about your connectors? There are several types of connectors available for 10GbE cables, all with varying degrees of supported lanes and speeds. The most widely used connector is the SFP+. If you want higher speeds you would bond multiple lanes, for instance bonding 4 of the 10GbE lanes to give you 40Gbps.So, which cable is the right cable? It depends on your environment, on the switch equipment you have and on what price and quality you want, if your current equipment does not suit your needs.When the requirement is for short runs – inside a rack, for example – 10GBASE-CR would be the best bang for your buck. You get the performance you want without paying the costs of fibre. If you need to get 10GbE in longer distances, but not quite in the miles range, using MMF cables such as OM3 or OM4 with SFP+ connectors would be a good option.

For anything that is beyond your data centre, the 10GBASE-LR or the other long-reach fibre should be used. However, if you are running fibre between floors of your building, the 10GBASE-LR can also be used. While most deployments of 10GbE use SFP+, you can still use 10GBASE-T if your switch and network adapters support it. Talk Google and you think search, ads and YouTube. Your second thought might go to Google Apps and Chrome.Say “Facebook” and what do you think of? A firm making fistfuls of money from ad men mining its members’ data.Their diaspora are different, as two former employees have come together to follow a common dream.Theo Vassilakis, a former Google engineering director who led on query engines, visualisation systems and data generation pipelines, and Toli Lerios, a former Facebook senior software engineer who worked on image and video algorithms, pushed the eject button from their respective motherships recently.Their new technology offering is called Quest, something they call a data compute engine from their firm Metanautix, which was founded in 2012 with $7m backing from Sequoia Capital.The idea is that using industry standard SQL you can search a multitude of big unstructured, structured and relational data sources through one engine. Metanautix Tuesday announced a free, single-user edition of Quest.

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