iPhone 5s的指纹识别功能安全吗？

    苹果（Apple）本月初发布了新款iPhone 5s，Touch ID技术是其中备受瞩目的新特性之一。这项技术可利用内置于Home键中的指纹扫描设备加密手机。用户只需轻触Home键就能解锁手机，甚至还能在iTunes上消费，而在此之前，用户必须先在手机上输入四位数的解锁码。

    不过，Touch ID功能真的安全可靠吗？它究竟是可有可无的新奇玩意，还是用户能真正可以信赖的安全管家？

    我看是后者居多。移动安全新创企业Lookout公司的安全研究员马克•罗杰斯表示，苹果的指纹扫描技术在方方面面完胜传统加密方法。据统计，仅有一半多的Android和iOS用户在使用四位数字解锁码。虽然解锁码能提高安全系数，但许多用户都不愿意在登陆前花几秒钟的时间来输入密码。罗杰斯解释说：“解码锁被人们看成是一种障碍，而人们会有意识地避免过多的障碍。”

    Touch ID能让这个过程更加简单，至少从理论上是这样。用户只需在使用前花费少许时间，扫描和存储指纹即可。以后，用户只需要像日常使用一样，轻轻触碰一下Home键就能解锁手机。如果Touch ID真的能达到如此效果，我想绝大部分iOS用户都会乐于使用这项新功能。用户几乎没有增加任何使用成本：只要轻轻点击即可。

    罗杰斯表示，就整体而言，指纹扫描技术的安全系数要高于传统的四位解锁码。即使在今天，复制指纹依然是一项异常复杂的工作，更不要说它高昂的成本——有人估算每次成本高达20万美元。虽然听起来有些变态，但截断的手指也无法解锁iPhone。（不过，它还能识别猫爪。）这就是说，除非遭遇有针对性的攻击，不然Touch ID绝不比之前的安全技术差，iPhone 5S用户完全可以放心。

    安全专家布鲁斯•施耐尔调侃说：“大家的手机里又不会有什么国家机密，对普通人而言，Touch ID的安全性足够了。”

    《财富》（Fortune）读者们，你们有什么看法？Touch ID是言过其实还是实至名归？请留下你们的宝贵意见。(财富中文网)

    When Apple (AAPL) introduced the iPhone 5s earlier this month, one of the features it touted was Touch ID, a fingerprint-scanner built into the home button at the bottom of the device. Users may simply touch the home button to unlock their phone and even authenticate iTunes purchases, instead of inputting a custom 4-digit passcode used by previous iPhones.

    But just how secure is Touch ID, really? Is it a nifty gimmick, or truly better security for user data?

    Likely the latter. According to Marc Rogers, a security researcher for the mobile security startup Lookout, Apple's implementation of fingerprint scanning trumps the old method for myriad reasons. Across both Android (GOOG) and iOS devices, just over 50% of users use the four-digit passcode feature. Having it boosts security, but it also seems many just can't be bothered with wasting a few seconds each time to log in. "People see them as barriers, and they try to avoid having too many barriers," explains Rogers.

    Touch ID should make the process easier, at least in theory. Initially, users have to to set up the feature by having their fingerprint scanned and stored on the device -- a process that takes several moments. From every instance on, unlocking the phone means simply pressing the home button as one normally would. If that's the case, more iOS users are likely to turn the feature on. It doesn't add a pesky extra step in everyday user experience: just touch and go.

    As for the tech itself, Rogers explains fingerprint scanning as a whole is more secure than the four-digit passcode. Copying someone's fingerprints remains a cumbersome process, not to mention pricey -- as much as $200,000, by some estimates. And at the risk of sounding morbid, using severed fingers apparently isn't an option either. (However, cat paws work.) Which is to say, that barring a targeted hack, iPhone 5s owners should rest assured their data is just as secure as it ever was.

    "It's your phone -- we're not launching missiles here," jokes Bruce Schneier, a security technologist. "We're looking for a little bit of security, and I think Touch ID is a really great idea for that."

    What about you, Fortune readers? Is Touch ID overhyped or a big step in mobile security? Weigh in the comments below.