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Blackboard with a diagram of a network of computers with the word 'Blockchain' in the middle.

3 Obstacles to Moving Social Media Platforms to a Blockchain

On average, there about 10 million active sessions a day on Taiwan’s version of reddit, a 25-or-so-year-old bulletin board system called PTT. That’s a respectable number considering Taiwan’s total population is 24 million. But lately the platform has been hit with many of the same problems that have muddied other social media sites—and now, its leaders are taking extreme measures to wipe it clean.

Last month, PTT’s administrators started developing a modified platform that could store data on distributed ledgers—permanent records shared among users themselves. Today, PTT’s servers hum on a National Taiwan University campus in Taipei—where it began as a student project. But this single entity is a clear target for authorities to pressure if they want to censor content.

If data is instead distributed across just enough independent entities, then the risk of censorship is much lower. And there’s another benefit: users would “own” their data and control their own privacy.

Chu Yichen, CEO of BiiLabs (a Taipei-based startup building the backend architecture, said, “it will be difficult” to create. There are three main technical roadblocks to decentralizing social media with distributed ledgers.

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Photo-illustration: iStockphoto

It’s Never Too Early To Think About 6G

5G report logo, link to report landing page

The first thought that popped into your head as soon as you read this article’s headline was likely something along the lines of “Wait, I thought we were still waiting on 5G.” And that’s true: This is the year 5G deployment is finally picking up steam.

But that’s precisely why ComSenTer, a multi-university research effort into the fundamentals of what 6G might look like, is already turning its attention to the next next generation of wireless. 5G will utilize higher frequency spectrum than previous generations in order to improve data rates. Insomuch as anyone has an idea of what 6G might look like, it’s a good bet that it will take that same tack.

“It’s not clear what 6G will be,” says Sundeep Rangan, the director of NYU Wireless, one of the institutions participating in ComSenTer. “If it is the case that 6G or other communications systems can benefit from very, very high frequency transmissions, we need to start looking at that now.”

Rangan adds that, “It’s premature to say that what we’re looking at will definitely be part of 6G,” stressing that what’s being investigated now is still fundamental research.

Even so, Mark Rodwell, ComSenTer’s director and a professor at the University of California Santa Barbara, says there are a few key demonstration projects ComSenTer is looking into. The first involves building a base station that can handle the frequency ranges expected to be part of future generations of wireless. ComSenTer, which is being funded by the Semiconductor Research Corporation, a consortium of heavy-hitters like DARPA, IBM, and Intel, is focusing its efforts on the 140-gigahertz, 220-GHz, and 340-GHz frequencies—all significantly higher than the 3.4 to 3.8 GHz band being leveraged for 5G.

Rodwell envisions a base station that could emit up to a thousand beams simultaneously. “What you’re looking at is four surfaces, each capable of 250 simultaneous beams,” he says. If each beam provided 10 gigabits per second, a single base station could transfer 10 terabits every second.

The higher frequencies also present challenges for handsets. The higher-frequency receiver components must be packed more closely together, introducing a risk of overheating. Signal loss must also be addressed. “Packet loss is phenomenally extensive at these frequencies,” says Rodwell.

The third major challenge is a question of math. “When a signal comes in [from a particular] direction, it’s hitting all the antennas,” says Rodwell. “Massive numbers of beams mean a lot of number crunching. You’ve got to sort all that out.”

ComSenTer’s areas of interest overlap in many places with technologies and techniques that were developed for 5G. One of the main challenges with millimeter waves, for example, is their relatively short range and an annoying habit of being easily blocked by buildings and even people. The higher gigahertz frequencies that ComSenTer researchers will be exploring will face those problems to an even greater extent.

Even so, Ali Niknejad, a professor at the University of California Berkeley and the assistant director at ComSenTer, sees potential for massive improvements over 5G. “When people talk about 5G and you look at the demonstrations they’ve done, they’re kind of artificial.”

5G has rightly generated massive hype regarding what it will do for applications including autonomous cars and virtual reality. As we noted in an earlier article, it will “allow for previously unachievable precision, data rates, and network capacity” that will “finally make technologies possible that engineers have worked on and struggled with for years.” But, at the end of the day, 5G applications remain constrained by a single-beam approach to data transfer. A system designed around hundreds of simultaneous beams—emitted at even higher frequencies—promises much higher data rates for our bandwidth-hungry society.

Of course, it’s not guaranteed that 6G will ultimately look anything like ComSenTer’s vision. Rangan says that it will be important to watch the development of 5G as it is deployed, to see what actually catches on. But that’s also a compelling reason to begin the research now, so that researchers can flexibly adapt to both 5G’s successes and shortcomings to build the wireless network that will follow it.

“This is research,” says Niknejad, “You’re looking at the future, looking well beyond today. 5G research started over 10 years ago. Looking at when 6G will come out, it makes sense to start it now.”

Digital sound waves

Interpol’s New Software Will Recognize Criminals by Their Voices

The world’s largest police network is evaluating software that would match samples of speech taken from phone calls or social media posts to voice recordings of criminals stored within a massive database shared by law enforcement agencies.

The platform, as described by developers, would employ several speech analysis algorithms to filter voice samples by gender, age, language, and accent. It will be managed by Interpol at its base in Lyon, France with a goal of increasing the accuracy of voice data, and boosting its reliability and judicial admissibility.

The development team completed successful field tests of the system in March and November 2017. Next up is a project review this June in Brussels.

While the system can process any “lawfully intercepted” sound, including ambient conversation, its expected use would be to match voices gleaned from telephone and social media against a “blacklist” database. The samples could come from mobile, landline, or voice-over-Internet-protocol recordings, or from snatches of audio captured from recruitment or propaganda videos posted to social media.

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Someone taking a photograph of text on a computer.

Hiding Information in Plain Text

Computer scientists have now invented a way to hide secret messages in ordinary text by imperceptibly changing the shapes of letters.

The new technique, named FontCode, works with common font families such as Times Roman and Helvetica. It is compatible with most word-processing software, including Microsoft Word, as well as image-editing and drawing programs, such as Adobe Photoshop and Adobe Illustrator.

Although there are obvious applications for espionage with FontCode, its inventors suggest it has more practical uses in terms of embedding metadata into texts, much like watermarking. “You can imagine that it would be used to provide extra information, such as authors, copyright and so on, about a document,” says study senior author Changxi Zheng, a computer scientist at Columbia University. “Another application is to protect legal documents: Our technique can be used to detect if a document, even when printed on paper, has been tampered with or not. It can even be used to tell which part of the document is tampered.”

Changxi and his collaborators will detail their findings in August at the SIGGRAPH  conference in Vancouver.

Another potential application of FontCode is as an alternative to QR codes. For instance, when people snap a photo of a poster with FontCode-modified text, their smartphones may be redirected “to a website or Youtube video about that poster,” Zheng says. “This is similar to what a QR code can do, but now without the need of putting a black-and-white pattern that can be distracting or compromise the aesthetics of the poster.”

FontCode embeds data into texts using minute perturbations to components of letters. This includes changing the width of strokes, adjusting the height of ascenders and descenders, and tightening or loosening the curves in serifs and the bowls of letters such as o, p, and b.

A kind of artificial-intelligence system known as a convolutional neural network can recognize these perturbations and help recover the embedded messages. The amount of information FontCode can hide is limited only by the number of letters on which it acts, the researchers say.

“Traditionally, a text document is meant to deliver information to the human only. Now we show that it can also deliver embedded information to digital intelligent systems, and the two parts of information delivery do not conflict,” Zheng says. “This is drastically different from existing methods such as QR codes or optical barcodes, which are meant to be read by digital systems but occupy a certain area on the paper.”

To account for potential distortions to text due to concerns such as lighting, blurriness, or camera angle, the scientists relied on the 1,700-year-old Chinese remainder theorem, which can help reconstruct missing information. This strategy could help recover hidden messages even when 25 percent of perturbations to texts are not recognized correctly.

Moreover, FontCode not only embeds messages in text, but can also encrypt them. For instance, users can agree on a private key that can specify the order in which hidden letters are read.

Although other methods exist to hide a message in text, FontCode's inventors say their new technique is the first to work independent of document type. It can also retain secret information even when a document or an image with text is printed onto paper or converted to another file type, they say.

The researchers have filed a patent for FontCode with Columbia Technology Ventures. In addition, “we want to extend this technique to other languages,” Zheng says. “We demonstrated using English in this project; it might require a bit of thought to extend it to other languages—especially the logographic languages, such as Chinese.”

Die photograph of the 500 C active down-conversion mixer.

Making Radio Chips for Hell

There are still some places the Internet of Things fears to tread. Researchers at the University of Arkansas and the KTH Royal Institute of Technology, in Sweden, are building a radio for those places. This month, in IEEE Electron Device Lettersthey describe a mixer, a key component of any wireless system, that works just fine from room temperature all the way up to 500 ºC. It’s the first mixer IC capable of handling such extremes.

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A dark sky with a tornado touching down

Spying on a Storm's Infrasonic Signals to Improve Tornado Warnings

Tornado survivors often compare the terrifying, deafening roars of a twister’s furious winds to the sound of a freight train. But storms also emit sounds that are inaudible to human ears right before producing a tornado. By detecting these infrasonic waves from miles away, researchers hope to develop an earlier, more accurate tornado warning system.

Today, weather agencies issue tornado warnings by closely observing storms for characteristic air movements. Warnings typically come about 10 minutes in advance. But most warnings are false alarms, says Brian Elbing, a professor of mechanical and aerospace engineering at Oklahoma State University. “Seventy-five percent of the time, tornadoes don’t occur,” he says.

The high rate of error causes ‘warning fatigue,’ which can be deadly. After a 2011 twister ripped through Joplin, Missouri, taking 162 lives, a federal report found that a majority of residents ignored or reacted slowly to warnings in the crucial minutes before the tornado hit.

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Close up of Vayyar Sensor Chip

Vayyar’s 72-Transceiver Radar Chip Sees Just Enough But Not Too Much

Last week, Israeli radar chip startup Vayyar Imaging released a new, higher resolution 3D imaging radar chip it expects will appear in applications as broad as home security, infotainment, and elder care. The resolution is higher, because it packs an unprecedented 72 transceivers on a chip that has its own digital signal processing circuitry. But the image it creates is nothing like a visible light camera’s, and that’s the key, according the company’s CEO and cofounder Raviv Melamed.

“One of the biggest problems, if you want to monitor people in their home, is privacy,” says Melamed. “Obviously, the best thing to have is a camera, but nobody really wants a camera in the house, especially when people can hack in.” He thinks Vayyar’s chip, which forms images at radar frequencies between 3 GHz to 81 GHz, can provide all the information needed for a home security system without any of the identifying data that impinges on people’s privacy.

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Gloved hands holding several used phones with a bin of other used electronics in the background

That New Memory Smell: Tech Can Tell if Your Flash is New or Recycled

Flash is designed to last a decade or more of use. A lot of the gadgets that rely on it are not. Shady recyclers have spotted opportunity in that mismatch, stripping out used chips and selling them as new. But engineers at the University of Alabama have come up with a straightforward electronic examination that can tell if a flash chip is new or recycled, even if that chip has only seen 5 percent or less of its life. And the technique is so straightforward that a smartphone app could run it on its own memory.

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This image shows the unfolded envelope before it is wrapped around a hardware security module.

The Unhackable Envelope

In a high-security computer center, there’s one machine that’s nearly impossible to break into. The systems that store and serve up cryptographic keys are physically protected from even the kinds of subtle attacks that belong in spy movies: x-rays, drill bits a fraction of a millimeter wide, electromagnetic snooping.

These so-called hardware security modules (HSMs) are protected by a battery-powered mesh of micrometer-scale wires embedded in special resin, and they store cryptographic keys in volatile memory that is automatically wiped if the mesh experiences even a minute amount of damage. The tiniest drill bit, for example, will result in open circuits, short circuits, or other changes in resistance that the system instantly detects.

It’s hard to say if anyone has ever succeeded in penetrating an HSM, because it’s not the sort of thing that companies crow about. But engineers from three institutions in Munich think they can do better. In particular, they see potential problems with the reliance on a battery and the memory system.

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On stage at the Brooklyn 5g Summit

5G Poised for Commercial Rollout by 2020

5G report logo, link to report landing page

Key figures in the development of 5G assembled last week at the annual Brooklyn 5G Summit in NYC. In two presentations and a panel discussion, attendees heard encouraging updates about the standardization process and its ability to support a global standards-based commercial rollout of the new wireless technology as early as 2019.

Perhaps most significantly, the experts are confident that everything is on track for Release 15 of the 5G New Radio specifications, scheduled for June of this year. Release 15 is critical to the development of 5G because it provides specifications that manufacturers can use to manufacture equipment. For instance, it will describe how 5G base stations will be configured and how those base stations will communicate with smartphones.

The good news is that a decision by the 3rd Generation Partnership Project (3GPP)—a unification of seven telecommunications standards development organizations—to accelerate the 5G New Radio (NR) schedule back in 2017 has not encountered any major setbacks.

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