Questões de Concurso

Internet Architects Warn of Risks in Ultrafast Networks

    If nothing else, Arista Networks proves that two people can make more than $1 billion each building the Internet and still be worried about its reliability.
    David Cheriton, a computer science professor at Stanford known for his skills in software design, and Andreas Bechtolsheim, one of the founders of Sun Microsystems, have committed $100 million of their money, and spent half that, to shake up the business of connecting computers in the Internet’s big computing centers.
    As the Arista founders say, the promise of having access to vast amounts of data instantly, anywhere, is matched by the threat of catastrophe. People are creating more data and moving it ever faster on computer networks. The fast networks allow people to pour much more of civilization online, including not just Facebook posts and every book ever written, but all music, live video calls, and most of the information technology behind modern business, into a worldwide “cloud” of data centers. The networks are designed so as to be always available, via phone, tablet, personal computer or an increasing array of connected devices.
    Statistics dictate that the vastly greater number of transactions among computers in a world 100 times faster than today will lead to a greater number of unpredictable accidents, with less time in between them.
    Mr. Bechtolsheim says that because of the Internet’s complexity, the global network is impossible to design without bugs. Very dangerous bugs, as he describes them, capable of halting commerce, destroying financial information or enabling hostile attacks by foreign powers.
    More transactions also mean more system attacks. Even though he says there is no turning back on the online society, Mr. Cheriton worries most about security hazards. “I ...... the claim that the Chinese military can take it down in 30 seconds, no one can prove me wrong,” he said.
    The common connection among computer servers, one gigabit per second, is giving way to 10-gigabit connections, because of improvements in semiconductor design and software. Speeds of 40 gigabits, even 100 gigabits, are now used for specialty purposes like consolidating huge data streams among hundreds of thousands of computers across the globe, and that technology is headed into the mainstream. An engineering standard for a terabit per second, 1,000 gigabits, is expected in about seven years.

(Adapted from. http://www.nytimes.com/2011/11/14/technology/)

Atenção: Considere o texto a seguir para responder às questões de números 56 a 60.

    Google Maps returns to the iPhone

    By Hayley Tsukayama, Published: December 13, 2012
    Google announced late Wednesday that its Maps app is back for the iPhone.

    Google Maps had been the default navigation service on the iPhone since the phone was first released in 2007. But earlier this year, Apple kicked the app off its mobile device and replaced it with its own mapping program, Maps. Many iPhone users balked at the notoriously inaccurate Apple navigation program and the loss of Google Maps, saying they would wait for Google to resubmit its app to the Apple store.
    The addition, however, doesn’t let Apple off the hook for improving its own Maps, which is playing catchup with Google as it tries to gather the amount and quality of navigation data it needs to bridge the gap between the two apps. Google Maps is known for being more comprehensive and generally more accurate than the other navigation apps out there.
    Google’s new iPhone mapping app adds features from Google’s Android that some Apple users have been longing for such as turn-by-turn directions for walking, mass transit and driving and a smooth integration of Google’s Street View technology. Navigation on the app is quick and intuitive.
    Google Maps also pulls transit information from several sites to make it easier to plan trips. In Washington, users can choose ..I.. I they want to go by bus, Metro or some combination of both and get clear route instructions with station names and clearly labeled bus stops.
    In this latest version, Google also makes it easier for users to flag the service if it gives the wrong directions. A shake of the iPhone triggers a dialogue box that offers the option to report errors or bugs directly to Google. There is at least one feature from Google Maps for Android that’s missing from the iPhone: the ability to save a portion of a map for offline use, which comes in handy when the phone’s battery runs low.

(Adapted from http://www.washingtonpost.com/business/technology/google-maps-returns-to-the-iphone/2012/12/13/80b92822-4520-11e2-
8061-253bccfc7532_story.html)