Encrypted and obfuscated? Your P2P protocol can still be IDed
Typical Web traffic is easy enough to spot: it uses TCP port 80. But plenty of protocols prefer to remain in the shadows and purposely make themselves difficult to identify—including Skype, BitTorrent, and eMule. If easy to identify, such protocols might make a tempting target for ISPs seeking to throttle back certain kinds of traffic. However, even these "obfuscated" protocols have a hard time hiding their secrets; encrypting the traffic can't keep them hidden, nor can certain tunneling behaviors that try to disguise one sort of traffic as another .
Who wants to identify traffic that hopes to remain hidden? Vendors of traffic analysis hardware, for one, who sell their gear to ISPs and must first be able to classify traffic before doing anything useful with it.
Read the comments on this post
Read More ...
Feature: Neither models nor miracles: a look at synthetic biology
The 20th century broke open both the atom and the human genome. Physics deftly imposed mathematical order on the upwelling of particles. Now, in the 21st century, systems biology aims to fit equations to living matter, creating mathematical models that promise new insight into disease and cures. But, after a decade of effort and growth in computing power, models of cells and organs remain crude. Researchers are retreating from complexity towards simpler systems. And, perversely, ever-expanding data are making models more complicated instead of accurate. To an extent, systems biology, rather than climbing upwards to sparkling mathematical vistas, is stuck in a mire of its own deepening details.Synthetic biology does away with systems biology's untidiness by focusing on individual parts, creating a tool set for engineering organisms unconstrained by biology as we know it, making the discipline more like software programming. But instead of modularity, synthetic biology often encounters messiness. What a particular “part” actually does depends on the rest of the system, so synthetic biology rediscovers the complexity it hoped to escape.
Read the comments on this post
Read More ...
Evolution, not revolution: a look at AMD's Bulldozer
STANFORD — In a presentation today at Hot Chips, AMD unveiled new details of two upcoming microprocessor architectures aimed at the server and mobile markets. Those architectures, codenamed Bulldozer and Bobcat, are AMD's first new-from-the-ground-up designs since the original Opteron, and Bulldozer in particular marks the biggest departure from existing hardware since AMD introduced the original K7 back in 1999. In this short article, I'll take a look at Bulldozer in order to explore the reasons why AMD made the design decisions that it did.
Read the comments on this post
Read More ...
While my Uzi gently weeps: Ars reviews, loves, Shank
Let's talk about how one kills the enemies in Shank. You can pounce on top of an enemy, pinning him to the ground with your body weight—as well as the knife that is now run through his chest. From there you can take out your handguns and shoot at other enemies from either side of the screen. The unlucky bastard you're crushing? Finish him off with your chainsaw.That's just the start. Use your shotgun for crowd control, pushing enemies off cliffs or onto train tracks. Grab enemies by the collar and stab them repeatedly with your knife. Climb up the side of a wall and shoot downwards at them. The options are overwhelming at first, and the timing for attacks is a little tricky to master, but once you learn the system you'll find some very entertaining ways to take out your opponents.
Read the comments on this post
Read More ...
Users are still idiots, cough up personal data despite warnings
Study after study has shown that users are the weak link when it comes to security. Some of it, however, is not their fault: best security practices often go against everything we know about human behavior or mental capacity. A study that will be published in the Journal of Consumer Research adds another one to this list. It turns out that the warning signs that might tip users off to a web site that's more likely to compromise their personal information actually causes many users to treat said information casually. The authors approached the issue with a simple question: what motivates people to reveal personal information on the Internet? Understanding the phenomenon could go a long way towards explaining everything from blogging to phishing victims, but the authors chose to focus specifically on whether people would hand over embarrassing personal information, including sexual habits and illegal acts. After several rounds of tests, they conclude, "A central finding of all four experiments, is that disclosure of private information is responsive to environmental cues that bear little connection, or are even inversely related, to objective hazards."
Read the comments on this post
Read More ...
Yahoo now officially powered by Bing in US, Canada
The first step of Yahoo's transition from an in-house search infrastructure to Microsoft's Bing platform is complete. Yahoo announced the completed conversion today: its Web, image, and video search experiences on both desktop and mobile devices are now being served up by Bing. Microsoft meanwhile noted that the conversion currently only affects Yahoo's English search results in the US and Canada, with other languages to follow "in the weeks and months ahead."
The change comes over a year after Microsoft and Yahoo agreed to partner on search and ads in order to combat Google. The Yahoo search results still have the same appearance, except for the 7.5 point text stating "Powered by Bingâ„¢" at the bottom of the page.
We contacted both Microsoft and Yahoo to find out which countries will get the Bing-powered-Yahoo next but neither company was eager to share. "At this time, Yahoo! has not given details on international rollout, but I will keep you posted," a Yahoo spokesperson told Ars. Microsoft was only a bit more helpful. "As soon as we are up and running in North America, we will begin the work of scaling out internationally," a Microsoft spokesperson told Ars.
As we noted on Bing's one year anniversary, Microsoft's offering has been gaining credibility where its predecessors failed. Depending on which market share numbers you follow, Bing should now have somewhere between 16 and 28 percent market share in the US thanks to Yahoo's help. The hope is that with the additional hits, Bing will over time learn to provide more accurate results as the number two search engine behind Google.
In addition to the search results in the center of the page, the two companies are also working on the sponsored results in the sidebars. The move of Yahoo's search ad infrastructure to Microsoft's AdCenter platform is due for completion "later this fall," but both companies have said they are willing to postpone the move till early next year as it may disrupt the holiday season. The revenue model for the Yahoo Search BOSS program still needs to be finalized, and many search-related tools for publishers will be released "in the months to come."
Read the comments on this postRead More ...
More evidence for 99¢ iTunes TV rentals, Apple TV makeover
Ninety-nine cent TV show rentals through iTunes are getting closer to reality, at least according to multiple sources speaking to Bloomberg. Three separate "people familiar with the plan" claim that Apple is in advanced talks with News Corp. to offer 48-hour rentals of popular shows from Fox, backing up previous rumors about Apple's push towards 99¢ shows.According to the unnamed sources, other networks, such as CBS and Disney, are also busy working out deals of their own with Apple. The shows would apparently work in the same way as current iTunes purchases—they would be playable on iPhones, iPods, iPads, and likely the Apple TV, not to mention your standard computer.
Currently, TV downloads from iTunes cost an average of $1.99 per show—just high enough to annoy many customers who are used to getting TV for free, but low enough that people pay it. A 99¢ TV rental would obviously be a little closer to free and, if the shows remain commercial-free like the rest of iTunes, would be an upgrade from watching them on the boob tube or Hulu.
The networks have been rumored to be hesitant about Apple's push, but it sounds like they're now more open to the possibility. After all, such a deal could help them boost revenue, especially when TV viewers seem to be canceling their cable subscriptions left and right.
The negotiations may also be tied to a major Apple TV update that is supposedly in the pipeline. Bloomberg's sources corroborated the many previous rumors about an updated Apple TV, including the introduction of a $99 version and a serious focus on streaming (Bloomberg claims the device will have a smaller hard drive than current models, though, while previous rumors say there won't be a hard drive at all). The new Apple TV may even get a new moniker, iTV, although already-existing trademarks make that more unlikely.
One thing for sure is that the buzz about the Apple TV and cheaper TV shows are beginning to reach fever pitch. It wouldn't be a surprise to hear an announcement about Apple's plans soon, as there's an expected September Apple event just around the corner.
Read the comments on this post
Read More ...
Wireless net neutrality so bad, Verizon already agreed to it
Verizon's Tom Tauke left the DC swamp this week for a stint in Aspen's alpine environs, where the Technology Policy Institute is hosting a conference. But the change of air didn't change what's on Tauke's mind: the fallout from the net neutrality policy framework agreed to by both Google and Verizon.Much of that fallout has focused on wireless—the Google/Verizon framework refuses to apply even minimal nondiscrimination rules to wireless (only "transparency" would apply). Verizon and other wireless vendors have recently been flogging the "wireless is different" mantra everywhere it can be flogged, and Tauke took his cat-o-nine-tails up to Aspen this week to flog the idea once more.
Read the comments on this post
Read More ...
New, inexpensive color e-readers have Android under the hood
Although Google's Android mobile operating system is principally designed for phones, it is also increasingly showing up on low-cost tablets and other kinds of mobile devices. The platform is rapidly emerging as a major contender in the e-book reader market, where it is attracting a growing number of hardware vendors.Barnes and Noble's popular Nook is arguably the most prominent Android-based e-book reader, but there are also a number of intriguing offerings from other vendors. Some are differentiating their readers by eschewing battery-friendly e-ink in favor of color LCD screens. These products take a more tablet-like approach and give users the advantage of a multifunction Internet-enabled device at nearly the same price point as regular e-book readers.
Read the comments on this post
Read More ...
Subscriber growth suddenly stops for cable TV industry
The number of people shelling out for cable TV is on the decline, possibly opening the door for newer TV models to finally break through to the mainstream. According to data gathered by market research firm SNL Kagan, cable companies saw a noticeable drop in the total number of subscribers during the second quarter of 2010, a first for an industry that has thus far seen nothing but growth.The number of cable subscribers dropped by 711,000, according to SNL Kagan, with six out of eight cable providers reporting their worst quarterly subscriber losses to date. Other parts of the industry were able to add just enough subscribers to make the net loss more like 216,000. Cable's share of the pay-TV market dropped slightly too, from 63.6 percent to just 61 percent during the quarter.
Read the comments on this post
Read More ...
US energy use is dropping and shifting to renewables
Analysts at the Department of Energy's Lawrence Livermore Labs have run the numbers on the US energy use in 2009, and come up with similar results to those obtained when examining the country's carbon emissions: energy use is dropping at a pace that is faster than would be expected based on the slowing economy alone. Even better, the growth in renewable energy, coupled with increased use of natural gas, is displacing significant amounts of coal.
Full-size (PDF). Image source: Lawrence Livermore Labs
According to the Livermore analysts, both economics and higher-efficiency appliances and vehicles helped push down the energy use last year, dropping consumption from 2008's 99 Quads. Coal and petroleum use both declined significantly (coal was down by 10 percent), with more efficient vehicles accounting for much of the latter. Lowered electricity use accounted for much of coal's drop, as did displacement by natural gas. But total natural gas use also dropped, at least in part because solar, hydro, and geothermal power all increased slightly, and wind power increased significantly. It's now at 0.7 Quads, and on pace to clear a full Quad within the next couple of years.
Renewables and nuclear are now supplying nearly 17 percent of the country's annual supply of energy, a fraction that's likely to grow if current trends continue. And most indications are that the trends will continue. The US auto fleet's fuel efficiency is slated to rise over the next several years, and the Obama administration is pushing to approve further wind and solar projects.
Read the comments on this post
Read More ...
Bacteria rush in to gobble up oil plumes from Deepwater
Researchers have discovered a large contingent of silent partners in the Deepwater oil spill cleanup—bacteria. Two samples of a deep-sea oil plume show that a high number of microbes have populated the oily area and are hacking away at the hydrocarbon concentration. The bacteria also seem to be using relatively little oxygen to metabolize parts of the oil, minimizing their own environmental impact.The samples of water were taken inside and outside a large oil plume about 6 miles from the well site and three-quarters of a mile below the surface, and date from a month after the Deepwater Horizon rig explosion. The scientists compared the chemical composition of the waters, as well as their microbial cell populations.
Despite the hostile environment, they found that the density of microbial cells inside the plume was twice that of uncontaminated water. The population was diverse, but certain types known to metabolize hydrocarbons using ambient oxygen and thrive in the presence of oil in cold water were particularly plentiful.
The authors of the paper found that, on average, the microbes were consuming hydrocarbons fast enough to give the plume's oil a half life of one to six days. The metabolization isn't yet taxing the water too badly, either, as the oxygen concentration inside the plume is only eight percent lower than normal, a figure consistent with other recent results.
Several factors contribute to the easy digestibility of the plume, including the fact that it's relatively light, dispersed, and composed mostly of the volatile stuff that the microbes love to eat. The microbes have also had lots of oil-eating practice from slower natural seeps in the area. This doesn't mean our troubles are over—many other toxic materials from the oil, such as methane, may persist. Still, it appears the bacteria may be able to pick up some of our deep-ocean-cleaning slack.
Science, 2010. DOI: 10.1126/science.1195979 (About DOIs).
Read the comments on this post
Read More ...
Windows DLL-loading security flaw puts Microsoft in a bind
Last week, HD Moore, creator of the Metasploit penetration testing suite, tweeted about a newly patched iTunes flaw. The tweet said that many other (unspecified) Windows applications were susceptible to the same issue—40 at the time, but probably hundreds.The problem has been named, or rather, renamed, "Binary Planting," and it stems from an interaction between the way Windows loads DLLs and the way it handles the "current directory." Every program on Windows has a notion of a "current directory"; any attempt to load a file using a relative path (that is, a path that does not start with a drive letter or a UNC-style "\\server" name) looks in the current directory for the named file. This concept is pretty universal—Unix-like systems have the same, called a "working directory"—and it's a decades-old feature of operating systems.
Read the comments on this post
Read More ...
Call of Duty: Black Ops: dedicated servers, dev console, mods
Modern Warfare 2 was not especially loved in PC gaming circles because of the lack of dedicated servers, the inability to tweak the game's settings, and the absence of support for user-created content. It looks like Treyarch is swinging for the fences with the latest entry in the series, which will include all three, although not at launch."We plan to open the game up for modding sometime post-launch. We do not know yet to what extent you will be able to mod the game. There are some purely technical issues related to engine and internal tool enhancements that do not easily fit the modtools paradigm," a developer said on the game's official forum.
Right now? They're focusing on finishing the game. "And, dev console: confirmed," the post continues.
Studio head Mark Lamia talked up dedicated servers earlier in the year. "We do work very hard to reconcile the desire to manipulate and modify those dedicated servers with offering them the persistent experience and benefits that the console system provides," he told CVG. "We're working very hard to marry those two things, so people can run dedicated servers and also participate in the communal experience the console players get to have, given they're all on first-party servers."
These are all steps in the right direction.
Read the comments on this post
Read More ...
George Lucas uses power of the (legal) force on Jedi Mind
George Lucas has set his sights on the makers of a wireless headset called Master Mind that claims to allow people to interact with computers through brainwaves. Jedi Mind, Inc. is the target of a new Lucasfilms lawsuit over trademark infringement, claiming that the company's products will hurt Lucas' business and cause confusion among consumers. Lucas has somewhat of a reputation of being intolerant of anyone using references to Star Wars in their products. The now-popular "Droid" mark for Android-powered smartphones was, in fact, licensed from Lucasfilm for this reason—otherwise, Motorola would have to use another, undoubtedly less catchy name.
With this fairly common knowledge, it's surprising that Jedi Mind, Inc. even moved forward with its company and product names in the first place. According to Reuters, Lucasfilm sent a cease-and-desist letter to the company in May of 2009, and then again in September of 2009 after Jedi Mind failed to phase out the Jedi-related marks. The two companies tried to settle out of court, but apparently failed, leading Lucasfilm to ask for $5 million in damages as well as injunctive relief.
Read the comments on this post
Read More ...
Supercomputers supermodel supermassive black holes
What happens when two black holes smash into each another? They form an even larger black hole while driving jets of relativistic matter into the far reaches of the cosmos. New complex computer simulations have attempted to give a glimpse into the explosion of electromagnetic and gravitational waves that result. The answers may tell us whether or not we could ever detect such a merger.A paper describing the simulations appears in the current issue of Science. It takes a look at what happens as two supermassive black holes dance around each another, accompanied by a conducting plasma and magnetic field. The emission of gravitational waves would carry both angular momentum and energy away, causing them to eventually collide and merge. The numerical simulations indicated that the particle jets that sometimes accompany black holes would align, thanks to an anchoring and alignment of the magnetic field that occurs as they merge.
An interesting side note mentioned by the authors is that stray charged particles will get caught up in the magnetic field and accelerate to enormous velocities. This acceleration will result in the particle radiating off enough energy to form electron-positron pairs from the vacuum which will be accelerated in turn. This process would repeat, producing a cascade of particles that populate the immediate region with a charged, conducting plasma.
All of the work is interesting to any theorist, but the results show what astronomers might look for as indications that an event of this sort has taken place. The electromagnetic energy of the collision can be transferred to kinetic energy through the plasma, which will bleed it off through synchrotron radiation. Those emissions could be detected with future X-ray telescopes out to a significant distance from the source (a redshift of z = 1).
Further in the future, joint X-ray-gravitational wave detectors will allow more refined observations of supermassive black hole mergers. The paper gives a scaling for gravitational wave power that should be detectable at even greater distances, back to redshifts of 5 to 10.
Science, 2010. DOI: 10.1126/science.1191766
Read the comments on this post
Read More ...
Together we kill: first look at Assassin's Creed Brotherhood
Just one year later, Ubisoft is returning to 15th century Italy with Assassin's Creed Brotherhood. Though it's being released so close to the well-received Assassin's Creed 2, Brotherhood doesn't seem to be a simple cash-in. Instead, it looks like an attempt to refine the formula further, adding new elements and improving the combat. Ars recently had the chance to check out the game during a hands-off developer walkthrough in Toronto, which showed off some of these new features.Read the comments on this post
Read More ...
Brain may take an acid trip into migraines
Migraines remain poorly understood and, partly as a consequence, we have little in the way of effective treatments. Although increased activity in the brain—both increased blood flow and elevated firing by nerve cells—has been implicated, the connection between those phenomena and the symptoms remains obscure. Now, researchers have identified a new gene that is mutated in individuals that have inherited a migraine disorder, and identified yet another factor that can contribute to migraines. The gene was isolated in patients that had both severe migraines, and a set of other disorders (glaucoma, kidney disorders) that have been associated with loss of a protein, the sodium-bicarbonate cotransporter (SLC4A4), that shuffles ions across cell membranes. Because its targets include bicarbonate, which can buffer against pH changes, some of the problems caused by its loss are associated with increased acidity of bodily fluids.
The simplest interpretation of the results would be that the problems in SLC4A4 are unrelated to the migraines, but the researchers had access to DNA from a panel of other individuals who suffer from inherited migraine disorders; they found four other individuals that also had mutations in SLC4A4, a result that is extremely unlikely to occur by chance. It appears that all of these individuals can make the sodium-bicarbonate cotransporter, but the protein never ends up on the cell surface, so it can't perform its normal function.
So, how could altered pH induce migraines? The authors note that SLC4A4 is expressed by astrocytes, brain cells that are closely associated with neurons. They propose that loss of the gene leads to locally-altered pH, which influences how the neurons release and retrieve ions when firing off nerve pulses. These changes could ultimately increase the neurons' activity, causing the onset of migraine symptoms.
PNAS, 2010. DOI: 10.1073/pnas.1008705107 (About DOIs).
Read the comments on this post
Read More ...
No comments:
Post a Comment