How Bitcoin Mining Works

How Bitcoin Mining Works

Technology  

In traditional fiat money systems, governments simply print more money when they need to. But in bitcoin, money isn’t printed at all – it is discovered. Computers around the world ‘mine’ for coins by competing with each other.

How does mining take place?

People are sending bitcoins to each other over the bitcoin network all the time, but unless someone keeps a record of all these transactions, no-one would be able to keep track of who had paid what. The bitcoin network deals with this by collecting all of the transactions made during a set period into a list, called a block. It’s the miners’ job to confirm those transactions, and write them into a general ledger.

Making a hash of it

This general ledger is a long list of blocks, known as the 'blockchain'. It can be used to explore any transaction made between any bitcoin addresses, at any point on the network. Whenever a new block of transactions is created, it is added to the blockchain, creating an increasingly lengthy list of all the transactions that ever took place on the bitcoin network. A constantly updated copy of the block is given to everyone who participates, so that they know what is going on.

But a general ledger has to be trusted, and all of this is held digitally. How can we be sure that the blockchain stays intact, and is never tampered with? This is where the miners come in.
When a block of transactions is created, miners put it through a process. They take the information in the block, and apply a mathematical formula to it, turning it into something else. That something else is a far shorter, seemingly random sequence of letters and numbers known as a hash. This hash is stored along with the block, at the end of the blockchain at that point in time.

Hashes have some interesting properties. It’s easy to produce a hash from a collection of data like a bitcoin block, but it’s practically impossible to work out what the data was just by looking at the hash. And while it is very easy to produce a hash from a large amount of data, each hash is unique. If you change just one character in a bitcoin block, its hash will change completely.

Miners don’t just use the transactions in a block to generate a hash. Some other pieces of data are used too. One of these pieces of data is the hash of the last block stored in the blockchain.
Because each block’s hash is produced using the hash of the block before it, it becomes a digital version of a wax seal. It confirms that this block – and every block after it – is legitimate, because if you tampered with it, everyone would know.

If you tried to fake a transaction by changing a block that had already been stored in the blockchain, that block’s hash would change. If someone checked the block’s authenticity by running the hashing function on it, they’d find that the hash was different from the one already stored along with that block in the blockchain. The block would be instantly spotted as a fake.

Because each block’s hash is used to help produce the hash of the next block in the chain, tampering with a block would also make the subsequent block’s hash wrong too. That would continue all the way down the chain, throwing everything out of whack.

Competing for coins

So, that’s how miners ‘seal off’ a block. They all compete with each other to do this, using software written specifically to mine blocks. Every time someone successfully creates a hash, they get a reward of 25 bitcoins, the blockchain is updated, and everyone on the network hears about it. That’s the incentive to keep mining, and keep the transactions working.

The problem is that it’s very easy to produce a hash from a collection of data. Computers are really good at this. The bitcoin network has to make it more difficult, otherwise everyone would be hashing hundreds of transaction blocks each second, and all of the bitcoins would be mined in minutes. The bitcoin protocol deliberately makes it more difficult, by introducing something called ‘proof of work’.

The bitcoin protocol won’t just accept any old hash. It demands that a block’s hash has to look a certain way; it must have a certain number of zeroes at the start. There’s no way of telling what a hash is going to look like before you produce it, and as soon as you include a new piece of data in the mix, the hash will be totally different.

Miners aren’t supposed to meddle with the transaction data in a block, but they must change the data they’re using to create a different hash. They do this using another, random piece of data called a ‘nonce’. This is used with the transaction data to create a hash. If the hash doesn’t fit the required format, the nonce is changed, and the whole thing is hashed again. It can take many attempts to find a nonce that works, and all the miners in the network are trying to do it at the same time. That’s how miners earn their bitcoins.

Google launches wi-fi network in Kampala, Uganda

Google launches wi-fi network in Kampala, Uganda

Technology  

Google has launched its first wi-fi network in Uganda's capital Kampala, as part of a project to broaden access to affordable high-speed internet.

The company is making the broadband wireless network available to local internet providers, who will then charge customers for access.

The web giant says the network is now live in 120 key locations in Kampala.

Official statistics show Uganda has about 8.5 million internet users, making up 23% of the population.

Google hopes that by improving internet capacity in the city, local telecom companies will then be able to offer faster, cheaper broadband access to their customers.

The company estimates that one day's unlimited data using the new network should cost 1,000 Ugandan shillings ($0.30, £0.20), although local providers will decide how much they want to charge for the service.

Critics say it would have been better to focus on Uganda's rural areas, where high-speed internet access is very limited.

The wireless network forms part of a wider project to improve web infrastructure in Africa, which has seen Google lay 800km (500 miles) of cables in Uganda to establish a fibre optic network.

There are now plans to expand the project to the Ghanaian cities of Accra, Tema and Kumasi.

In October, Facebook announced its own initiative to increase access to the internet in Africa by using satellites.

Kia announces £1.3 billion investment in driverless car technology

Kia announces £1.3 billion investment in driverless car technology

Technology  

Kia has revealed ambitious plans to develop entirely driverless cars by 2030.

The Korean car company has said it will invest £1.3 billion into the development of the technology by 2018. The first goal will be to introduce partially-autonomous driving technologies, such as a remote parking system that will make a car park itself at the press of a button on the keyfob. Cars with this technology could be on the road by 2020.

Hyundai Group’s vice president, central advanced research and engineering institute, Tae-Won Lim, said: “Fully-autonomous vehicles are still some way off, and a great deal of research and rigorous product testing will need to be carried out to make the ‘self-driving car’ a reality. Kia is still in the early stages of developing its own technologies, and we are confident that the latest innovations – both partially and fully autonomous – will ultimately make driving safer for everyone.”

Smart Kia cars of the future will have a range of technologies focusing on three areas so they can function without a driver.

They will have new sensors so they can detect other vehicles, read the road ahead and identify poor driving conditions. Advanced computing systems will enable the cars to make decisions based on the information gathered by the sensors. And the computers will use their active mechanical and electronic systems to drive the car.

In order to reach this stage Kia will first work on three semi-autonomous systems. Highway Driving Assist will comprise a lane guidance system and smart cruise control. Traffic Jam Assist will take over around town and prevent the vehicle getting too close to the car in front. And, our favourite, the Remote Advanced Parking Assist System, will enable a driver to park their car simply by pressing a button on the keyfob.

Drone Maker DJI Adds Technology to Limit Where Its Machines Can Fly

Drone Maker DJI Adds Technology to Limit Where Its Machines Can Fly

Technology  

DJI, a Chinese company that makes more small-scale drones than anyone else, announced on Tuesday a new, so-called geofencing system, which is a way to better control what a drone is flying over.

The system, built on flying restrictions DJI first introduced in 2013, promises continually updated information on a machine’s airspace. Information on something like an airport is already in the system; this might add something like a request by emergency personnel not to fly over a forest fire. 

“This is an example of the technology empowering operators to make smart decisions,” said Brendan Schulman, vice president of policy and legal affairs at DJI. “It’s an example of how technology solutions can address concerns.”

What action to take is often up to drone’s pilot, though it is clear that freedom of the skies faces increasing limits. The system has built-in restrictions around sensitive locations such as prisons and power plants, where potential payloads, not the flying itself, are a concern. 

By default, the drone won’t be operable in such places, though users who open DJI accounts will be able to self-authorize flights in some locations. 

Registering for those accounts will require verification from a credit or debit card, or a mobile phone number. DJI will apparently make the information available if there are legal investigations of flights, but it won’t collect or store the information for any other purpose for the free service. For national security locations (the company mentioned all of Washington as a “prohibited area”) even the override won’t work.

The move appears to be at least in part an effort to curb increasing regulation of drones.

Mr. Shulman spoke about privacy and safety issues expressed by individuals and regulatory authorities.

The Federal Aviation Administration, which is responsible for the conduct of most of what flies around, wants to register drones, and is mulling how to further control an airspace suddenly plied by millions more operators.

As a result of new regulations, many companies besides DJI have taken steps to influence the rule-making. A number of interested parties, including Google, Amazon, GoPro, Parrot and 3D Robotics, are participating in the F.A.A.’s registration task force.

While DJI’s effort, which will go live in December, is proprietary, it shows a trend of building more awareness into the systems, which may become common among drone makers. It also shows an interesting conflict in building this artificial intelligence: DJI is leaving how to treat information about new “no fly” areas up to individual pilots.

One reason for this may be to avoid liability, either from offering a product that unnecessarily limits its buyers’ or from offering a product whose artificial “fencing” technology fails, opening it to lawsuits.

To Mr. Schulman, the new industry of drones is being unfairly singled out. “There is no other technology whose functionality is disabled by geography,” he said. “Your car’s speedometer goes to 100 miles per hour or more – it’s up to individuals to use that properly.”

Whether the government, from federal agencies to local municipalities, feels the same way about robots in space remains to be seen.

Lenovo Y50 review: Good for gamers.

Lenovo Y50 review: Good for gamers.

Technology  

Lenovo Y50 review: Design

The 15.6-inch Lenovo Y50 isn't a hybrid, something that tries to be a portable laptop as well as a gaming powerhouse. But, at 2.4kgs, it is a lot lighter and less bulky than one of its obvious rivals, the Asus G751. Hardly a featherweight, but that's as much as a kilogram lighter than some of the competition. Just taking it from one room to the other isn't going to make your groan.
It's 24mm thick too, getting us dangerously close to the sort of shape and weight that makes it seem you could slip it into a rucksack and use the Lenovo Y50 as a proper portable machine. Let's be clear: it's not one. If an Ultrabook is what you're after, then go buy one.

The Y50 isn't the loudest-looking gaming laptop around, though. Perhaps we've just been desensitised by stacks of laptops that look like they've had supercar exhausts bunged onto them, but we wouldn't be worried to pull this thing out in public as if it were a standard laptop. The Lenovo Y50 has a hint of gamer style, but it's not to excess.

Its lid is cross-hatched metal, as is its underside. The inner bits are soft-touch plastic, which feels nice on the fingers. There's not much in the way of obvious design compromise, although the metallic bits do feel like an ultra-thin veneer on top of a plastic frame when compared to something like a MacBook Pro. Still: how else do you get a gaming laptop this thin and light?

Lenovo Y50 review: Heat

The downside of making a laptop with a serious CPU and GPU combo this petite is how to deal with heat. The Lenovo Y50 is very much a case of when the screen's on, the fan's going on too. Even the lightest of tasks sits on a bed of subtle whirring caused by the fan. Its sound isn't offensive, but it's something to bear in mind if you're going to be working in quiet rooms half the time.
It's reasonably good at dispersing heat evenly, though, with outlets in the hinge and a big grille on the bottom ensuring there are no worrying hot spots. Just make sure there's room for that bottom grille to breathe, ok? It's also fairly happy with a bit of on-the-knees gaming, the grille seemingly positioned to avoid that area.

Lenovo Y50 review: Screen

One part of the gaming laptop's setup that can often be overshadowed by the specs of the GPU is the display. This spec matters, a lot.

Screen quality was perhaps the biggest issue with the 1920 x 1080 panel in the 2014 Lenovo Y50, but that has been radically improved by switching to IPS panels across the board for the 2015 model. None of that TN rubbish to be found here.
There are two options: a 4K (3840 x 2160) screen and a regular Full HD (1920 x 1080) one, the latter lower-resolution one which we're looking at here. Like an awful lot of game machines, it's a matte finish and is not touch-sensitive.

The big improvements over the older 1080p Y50 versions are in colour fidelity and angled viewing, having gone from pretty dreadful to pretty good. Colours look natural and while there's a bit of brightness loss at the steepest angles, what's being displayed is still visible from any angle you pick.
There are just two bits that could be better. Maximum brightness isn't going to sear any eyeballs, so we ended up using maximum brightness even with normal indoors conditions. Anything much lower just looks dim. This isn't a killer flaw when the Lenovo Y50 has a reflection-reducing matte screen, but its matte finish isn't quite the best we've seen at defusing those light sources either.

Lenovo Y50 review: Specs and performance

Upgrading to the 4K version is tempting, but a 1080p panel is actually a pretty good pairing for the hardware here. The Lenovo Y50 has a GeForce GTX 960M GPU and an Intel Core i7-4720HQ quad-core 2.6GHz CPU, enough to play just about any game at 1080p with high or medium settings, at a good (30fps-plus) frame rate.
Real gaming nuts might want to upgrade to the GTX 980M, but good luck finding such a laptop for under £1,500. This will do the trick for most of you.

What it doesn't have, though, is a proper SSD. Instead, the Lenovo Y50 uses a 1TB 5400rpm (i.e. slow) hard drive with an 8GB SSD partition to help grease up its performance when booting up and coming out of sleep. We've been spoilt by using so many SSD options over the last couple of years, and a hybrid drive just isn't the same. Booting up is a touch slow, as is returning from sleep.
It's funny to think that, while incredibly powerful, the Lenovo Y50 can at times seem slower than a much less capable machine. Still, if you care more about playing high-end games and editing video than how quickly it loads Windows 10, then this laptop is a great deal.

Having such a power-focused processor means the Y50 doesn't last too long off a charge though. We got around three hours before it shut off, which just isn't close to enough if you're after a portable work computer. Go with 4K and we suspect that'll be even less. Gaming performance is also severely throttled when not plugged-in.
So it's slim-ish and light-ish, but the Y50's portability is limited.

Lenovo Y50 review: Keyboard and trackpad

There are just a few other little niggles you need to consider before taking the Y50 plunge too. First, while the keyboard is pretty neat in some respects, with an attractive red backlight and decent key action, in fitting-in a numerical keypad it has had to seriously chop into some of the important keys. The shift keys are small, as is the backspace. You'll probably get used to it before too long, but it's not every typist's dream.

Then there's the trackpad, which we found a bit more of a long-term niggle. The size, the texture and the feedback of the click are all fine. However, a combo of picky zoning and that it's shifted a bit too far to the left of the Y50 mean it can feel unresponsive in use unless you shift your right hand unnaturally close to your left. Next to a good Ultrabook pad or a gaming one with properly contoured buttons, it's just a bit annoying and feels fiddly. This Lenovo, therefore, works best with a mouse attached.

There are also no ultra-hardcore macro buttons on the keyboard, used to programme sequences of key presses for tasks you'll have to repeat a lot. Still, the Lenovo Y50 isn't really a laptop for that crowd.
It even caters for those older gamers out there who, shock horror, still own a collection of disc-based PC games. Nope, there's no optical drive on the Lenovo Y50's side - instead there's an external drive in the box that just plugs into a USB port without needing its own separate power.
There are also plenty of connections on the Lenovo Y50's sides. There are three USB ports, a full-size SD card slot, HDMI and Ethernet. That's more than enough to let the thing work as the brain of a desktop-style setup.

If the Lenovo Y50 is going to sit on a table or desk somewhere as a home gaming rig, you'll probably want to get a headset or some speakers involved, though. While a little sub unit at the bottom of the laptop gives the sound a good thud of low-end output, the actual sound quality is just OK, without the bass/treble integration, balance or simple fidelity of the best laptop speakers.

Verdict

The Lenovo Y50 is a good-value gaming laptop, and a pretty aggressive competitor to other laptops in this class like the Acer V Nitro and the various MSI options around the price, including the GS20.
Last year the Y50 was a bit of a dodgy option given its limited screen quality, but in the 2015 upgrade to IPS panels (for both the 1080p and 4K resolutions) and the bump from a GTX 860M to GTX 960M GPU (a slight but worthwhile upgrade) Lenovo has solved some, if not all, of its problems.
We don't love the trackpad or the battery life, but if you're after a sub-£1,000 gaming laptop with a bit of gamer-style design flair, this is one of your best bets.

Dell reportedly launching takeover of EMC to create computing colossus

Dell reportedly launching takeover of EMC to create computing colossus

Technology  

Dell is reportedly offering about $US33 a share to acquire EMC Corp, in a deal that would create a computing colossus and help both companies cope with a demand slowdown.

The proposal includes a tracking stock in VMware valued at about $US8 a share that would be issued to EMC shareholders, said a person familiar with the story. A deal may be announced as soon as Monday, the person said.

Dell is speaking to banks about raising at least $US40 billion to finance the purchase, a person with knowledge of the matter has said.

A deal would bring together the largest storage maker and the No. 2 server company as the industry undergoes rapid change with the shift to mobile and cloud computing.

Dell, which was taken private for about $US25 billion in 2013, will use the combination to expand its product lineup in high-end data storage equipment as it tries to lure customers away from Hewlett-Packard Co. and other rivals.

For EMC, the agreement resolves a long overdue leadership succession and a standoff with activist investors.

The current plan would have Michael Dell run the combined entity, a person with knowledge of the matter has said.

EMC and Dell both need ways to manage a slump in their main businesses, with EMC weighing strategic options amid pressure from shareholder Elliott Management Corp.

Though the combination would be costly and difficult to finance, it would provide a one-stop shop for EMC's digital storage products with Dell's servers, which help businesses tackle mammoth computing tasks.

JPMorgan Chase & Co., Barclays Plc, Bank of America Corp., Credit Suisse Group AG and Deutsche Bank AG are among the banks that have been approached about financing the deal, people said.