Mobile Security 101: An Executive Guide to Mobile Security
- — 20 November, 2008 12:09
- Where do I start when securing mobile devices?
- Who is responsible for device security?
- What security do mobile devices need?
- For the mobile devices I do need, isn’t password protection sufficient?
- So how do I secure the data itself?
- How do I manage passwords and encryption across the devices?
- I can’t find sufficient security tools for PDAs, smart phones and so on. So how do I handle them?
For the mobile devices I do need, isn’t password protection sufficient?
Enforced password protection is a great first step, so if the devices are lost or stolen, they can’t easily be used. Be sure that all log-in settings require the user to type in a password — if the laptop or PDA logs itself in to your network, you’ll now have a significant breach potential. Be sure that the password is complex enough (at least eight characters, including a mix of numbers and letters) to resist hacking but not so difficult that users tape them to their devices. Also pay attention to how long a device may be idle before a password is required to use it again, suggests Paul Kocher, chief scientist for cryptography at technology consultant Cryptography Research. A long idle time will let someone walk away with a laptop at an airport or café and still have access to its contents, while a very short time-out period will require users to constantly enter their passwords, making them accessible to shoulder-surfers. A good rule of thumb is that two to five minutes of inactivity should trigger a password request.
If the data is particularly sensitive, you may want to use a second form of authorisation — such as a smart card reader, fingerprint reader, SecurID token or challenge/response system — so that a thief needs more than a password to access the device. Note that this second-authentication strategy is more plausible on a laptop than on handheld devices such as PDAs, for which there are typically no such hardware tokens available.
But password protection (even when augmented with a second form of authentication) by itself won’t help secure the locally stored data. If a data thief removes the hard drive from a laptop, the data is easily opened from another computer.
So how do I secure the data itself?
For data that must be stored on a mobile device, use whole-disk encryption secured by a password so that if the devices are lost or stolen, the data on their drives can’t be used. (Do the same for PCs in publicly accessible locations — they can be stolen, too.)
Although the current versions of Windows, Mac OS X and Linux include folder-based encryption, all it takes is a user not storing files in the protected folders for them to become accessible to a data thief. By contrast, whole-disk encryption protects everything on the drive, so you don’t have to worry whether users are putting company data in the right folder or if they have turned on file-by-file.
And there’s a bonus: Encryption provides you an automatic pass from having to publicly disclose the loss of devices that contain consumer information in the 33 states that require such disclosure (as of this writing).
Keep in mind that while modern laptops can run whole-disk encryption with minimal impact on performance, most handheld devices don’t have the horsepower to effectively run encryption. (The BlackBerry is an exception.) Some phone-based devices let you lock them out or zap their contents if they are lost or stolen, using their mobile phone connections to transmit a lockdown or kill. For other devices, a strong password may be your only real protection. Therefore, you may need to limit these devices to storing data you can afford to lose. But that decision can be tricky: Is an executive’s address book or schedule business-critical information that shouldn’t be risked, or is the convenience of mobile access worth the risk of loss or theft?