During the 1990s, many believed satellite phones were the future of mobile communications. Rapidly expanding terrestrial cellular networks gobbled up most of the market instead. Still, satellite phones retained some technical advantages over cellular ones, principally in remote or rugged areas that are difficult to cover economically with cell towers. Now the TerreStar Genus smart phone is combining the best of both worlds, using a cellular connection when available and tapping into a satellite feed when people wander out of range of a cell tower.
Google gave the first demonstration of its Chrome operating system today, at the same time opening the source code to the public. The company highlighted features that have grown out of what vice president of product management Sundar Pichai called "a fundamentally different model of computing." Unlike other operating systems, which merely incorporate the Internet, Chrome is completely focused on it.
The Chrome OS is based so aggressively on the Internet that devices running it will not even have hard drives, Pichai said, emphasizing that "every app is a Web app." All data will be stored in the cloud, and every application will be accessed through the Chrome browser. Because of this, he added, users will never have to install software or manage updates on the device.
The user interface closely resembles the Chrome browser. When the user opens applications, they appear as tabbed windows across the top of the screen. Users can stick their favorite applications to the desktop with one click, creating permanent tabs for them.
Pichai coyly demonstrated the way the Chrome OS can deal with competitors' file formats. He inserted a USB drive into a laptop running Chrome OS, launching a window that showed that the device contained several Microsoft Excel files. When he clicked on one of the files, the system automatically pulled up the Windows Live Web-based version of Excel, opening the file inside.
"It turns out that Microsoft launched a killer app for Chrome OS," Pichai said, adding that anyone who writes a Web application is writing an application for Chrome by default.
The effect, Pichai hopes, is "speed, simplicity, and security." Today's version of the operating system can boot up in seven seconds and open a Web application in an additional three, he said. Google engineers are working to make those times shorter.
The implications of the Web-focused design were spelled out more fully by Matthew Papakipos, engineering director for Chrome OS. Part of the security scheme for Chrome is that it's hard to make any unauthorized changes to the system, he explained. The root filesystem, which stores the core files needed to make software run, is stored in a read-only format. On top of that, every time the user boots the machine, Chrome OS verifies cryptographic signatures that ensure that the operating system software is properly updated, and matches the build Google has approved.
If the system fails any of these checks, the operating system automatically launches into a recovery procedure and reinstalls the correct version of Chrome, Papakipos said. Normally, reinstalling an operating system is a painful process because of the effect that has on the user's data, settings, and applications. In the case of Chrome, he noted, all of that information will remain unaffected in the cloud.
Some data, such as Wi-Fi settings, is cached on the machine, but Papakipos said this is only to make the system work faster. The data is always synced back to the cloud. The vision, he added, is that a user could eventually get a new device, log in, and find everything running just as it had before, with all the settings still in place.
A study that involved downloading more than three million Facebook profiles has provided the largest-ever snapshot of the methods used by spammers on the world's biggest online social network.
The study, led by researchers at Northwestern University, turned up hundreds of thousands of spam messages, most of which were sent by compromised user accounts in coordinated campaigns similar to those carried out by e-mail spammers.
"For normal users, it mostly remains a myth," says Yan Chen of Northwestern, whose team led the study, "but spam has been a big problem to Facebook."
Reports of user credentials being sold online also motivated the researchers, says Ben Zhao at University of California, Santa Barbara, who with a colleague also contributed to the study, which will be presented at the Internet Measurement Conference in Melbourne, Australia, next month.
Zhao's group had previously collected a dataset of around 11 million Facebook profiles by exploiting the now-discontinued Facebook feature that caused people belonging to regional "networks" to share their profile information with other users by default. Three months worth of data, collected in mid-2009 and representing around 3.5 million people, were used in the study.
The researchers searched for spam in 190 million wall posts--messages posted on one user's profile page by another user--by hunting for Web addresses, even if those addresses were deliberately obscured. Wall posts were grouped into clusters containing the same Web addresses before the malicious clusters were separated from those not sharing spam links by screening the addresses using Web security services.
Altogether 200,000 spam posts from 57,000 different user accounts were picked out from 2.08 million posts containing Web links. These spam posts were generated by 23 million users in total. The study is the first to examine spam activity and features at scale, says Zhao, and it shows Facebook is now a major platform for such activity. "The results are quite surprising to me -- that even last year there was so much activity," he says. "I think this is the harbinger of things to come, as Facebook attracts more of the wrong kind of attention."
Many messages tempted users with offers of free swag such as ringtones, or used a social trap like announcing that someone had a "crush" on them. Around 70 percent of the messages were "phishing attacks," meaning they directed users to websites that attempt to trick them into divulging personal information. But most were attempts to gain Facebook account details, a strategy that could help send out more spam.
"We expected that attackers would mostly create new accounts to send spam attacks, but in fact, most are sent via compromised accounts," says Chen. "That may be harder than creating new accounts, but it is more effective to send spams to real friends."
Different accounts often sent the same spam, sometimes in simultaneous bursts of activity. "These are coordinated spam campaigns, as we see in e-mail spam," says Zhao.
Search the Internet, and you'll find hundreds of applications designed to help you collaborate with other people more effectively. But examine your own habits, and you'll most likely find that you use just one piece of software for that purpose: an e-mail client.
You're not alone. A recent Forrester Research study found that 83 percent of business users typically send e-mail attachments to colleagues rather than using collaboration software. According to a recent survey by technology consulting company People-OnTheGo, the average information worker spends 3.3 hours a day dealing with e-mail, and 65 percent of such workers have their e-mail client open all the time.
Even Facebook, which once seemed like a likely replacement for e-mail, at least for the young and plugged-in, has acknowledged that e-mail isn't going anywhere. On Monday, the company announced a new messaging service that integrates external e-mail with its own internal messaging system—an admission of the staying power of e-mail, and an attempt to enhance its functionality.
Other software makers seem to have accepted that they'll never pull people's attention away from their e-mail in-boxes. Instead, they're looking to add new collaborative and social capabilities to e-mail.
"It's clear that e-mail is being used and even abused," says Yaacov Cohen, CEO of Mainsoft, a company based in Tel Aviv, Israel, that sells a plug-in called Harmon.ie. The plug-in links an e-mail application to a collaboration platform such as Google Docs, and to a person's social networking profiles, calendar applications, voice over Internet protocol software, and so on. To share a document using Harmon.ie, a user drags it from a sidebar to the body of a message, where it becomes a link. When the recipient clicks on the link, she is taken to the document stored in the chosen collaboration software. Using e-mail alone for collaboration creates confusion and overloads in-boxes, Cohen says.
Memory flexing: Nanowire transistors that switch between four different conductance states can be made on plastic substrates.
Credit: Junginn Sohn, Cambridge Nanoscience Center
Computing
Bendable Memory Made from Nanowire Transistors
A new type of device could ultimately hold more data than flash memory.
Wednesday, October 20, 2010
By Prachi Patel
Researchers in the U.K. have made a new kind of nanoscale memory component that could someday be used to pack more data into gadgets. The device stores bits of information using the conductance of nanoscale transistors made from zinc oxide.
The researchers published a paper about a prototype memory device fabricated on a rigid silicon substrate last week in the online version of the journal Nano Letters. They are now testing flexible memory devices in the laboratory, says Junginn Sohn, a researcher at the University of Cambridge Nanoscience Center and lead author of the Nano Letters paper.
The nanowire device stores data electrically and is nonvolatile, meaning it retains data when the power is turned off, like the silicon-based flash memory found in smart phones and memory cards. The new memory cannot hold data for as long as flash, and it is slower and has fewer rewrite cycles, but it could potentially be made smaller and packed together more densely. And its main advantage, says Sohn, is that it is made using simple processes at room temperature, which means it can be deposited on top of flexible plastic materials. Nanowire memory could, for instance, be built into a flexible display and could be packed into smaller spaces inside cell phones, MP3 players, plastic RFID tags, and credit cards.
Flash memory elements contain transistors that store bits of data (a 1 or 0) using the presence or absence of charge on a gate electrode. However, like other silicon-based electronic devices, flash faces physical limits in terms of how much it can be miniaturized. Memory elements are already at 25 nanometers, translating to data densities of one terabit per square inch, and are projected to reach their minimum size limit of about 20 nanometers by late 2011. Companies are increasing flash memory densities by packing twice the amount of data by storing two bits, or four values, in each cell: 00, 01, 10, and 11.
The nanowire device can also store four values, as different levels of conductance. It is based on a zinc-oxide nanowire transistor, which the researchers make by placing a nanowire on a silicon substrate and depositing source and drain electrodes at either end of the wire. They coat the wire with barium-titanate nanoparticles and deposit an aluminum gate electrode layer on top.
A positive gate voltage builds up positive charges on each nanowire and puts the device in a high conductance state. A negative voltage switches it to a low conductance state. The researchers used four different voltages to create four conductance states.
With iOS 4.2, iPads get a new Folders feature that lets users group app icons together.
Change can stoke conflicted emotions in a computer user. There's the thrill of the new. Then there's the dread of problems that may erupt when the old meets the new. Admittedly, I felt those qualms when I prepared to upgrade my iPad to the latest version of its operating system, iOS 4.2. As it turns out, my fears were unnecessary.
At first I was hesitant to upgrade on the first day the new version was available. Typically, the pent-up demand for something that's received the volume of ink and electrons that this edition of iOS has garnered swamps a company's servers, so I was surprised with how smoothly and effortlessly the upgrade occurred. There was narry a hiccup, except for an annoying message that kept telling me I was going to lose some purchased programs if I didn't backup my iPad. Problem was, the message kept popping up even after I backed up my iPad.
When I booted up my iPad for the first time under 4.2, I noticed that the wallpaper had changed -- it was simulated drops of water on a gray background. The simulation was so good, that I tried to wipe the drops from the screen a few times before realizing they weren't real.
Other than the new wallpaper, the iPad appeared to be unchanged. That was comforting -- familiarity always is -- but disquieting, too, because I was anxious to take the new features for a spin. After fumbling around with my apps for a bit, I decided to accelerate the discovery process and downloaded the iPad user's guide from Apple's website, which has been recently revised to accommodate the changes brought to the tablet by iOS 4.2.
Better Organization With Folders
Since my app library has grown to three screens of programs, one of the first new features I tried was Folders. Creating new folders was incredibly simple. You simply touch and hold any app's icon until all the icons on the screen start jiggling. Then you drag one icon onto another and a folder is created.
To edit a folder, you touch and hold its icon. A palette will appear containing flashing icons of the apps in the folder. From that view, you can remove apps from the folder or give it a new name.
Folders is just what the doctor ordered for organizing apps on the iPad. It cuts down on swiping from screen to screen, and it makes it easier to associate apps with groups where they can be more easily found.
Another feature 4.2 brings to the iPad is multitasking. That's activated by double pushing the the tablet's home button. When that's done, the screen of the iPad will gray out and a bar appears on its bottom displaying the apps that are active.
Whenever you use an app, it's automatically added to the multitasking bar. That means if you want to shut the app down, you'll have to touch and hold its icon on the bar, wait for the jiggling to start and close it. It's a bit inconvenient.
Become a Multitasker
Multitasking really speeds up moving from app to app on the iPad, and so far, true to Apple's claims, I haven't seen a hit on the tablet's performance. However, it's still early in the game, and I am obsessive about closing apps that I've finished using and not letting them linger on the multitasking bar where they can sap processing power.
Another benefit of mulitasking is the ability to run a music service like Pandora or play cuts from iTunes in the background while working with another app in the foreground.
When you right swipe the multitasking bar, controls appear for launching iTunes, controlling the tablet's volume and brightness, playing and jumping between songs and locking the screen orientation.
The slider button on the side of the iPad that was originally the orientation lock is now a mute button. This change has upset some souls in iPadland, but personally, I always had trouble locating that button when I wanted to lock the screen orientation and find the change more convenient.
Text Search on Web Pages
With 4.2, Apple has made it easier to print from the iPad. It's really easy if you have a printer that supports AirPrint; less so if you don't.
AirPlay support has also been added to the tablet's capabilities. Coupled with multitasking, that feature allows you to do things like beam video from the iPad to Apple TV while surfing the Web.
For gamers, Game Center, Apple's online gaming service, has been added to the iPad mix. With one Game Center ID, you can pick up your game activities from any iOS powered device.
The iPad's mail program has also been improved. It now has a unified mailbox where messages from all email accounts are aggregated. It also supports conversation threading. What's more, you can reply to invitations directly through the iPad's calendar app.
A small but productive feature has been added to Safari. It allows you to search for text on a Web page. When you type a search term into the search field at the top of the browser, not only will a list of Web search suggestions appear, but also an option for searching for the term on the page.
This latest version of iOS 4.2 is an iPad owner's dream. It adds powerful features that can increase productivity without disrupting the old look and feel of the device.
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