Although most USB memory sticks have no moving parts and thus are considerably less prone to mechanical wear than their older and larger counterparts, loss of data can still be an issue. Aside from mechanical failure, data can be lost by accidental erasure, or overwritten. No write capable media device is immune to this risk. The best safeguard against loss of data is frequent and proper backups, as with any other media type. Because of their propensity for physical loss USB memory sticks are best suited as intermediary storage, so it isn't advisable to store the only copy of an item on the memory stick.
Loss of Media
Data loss can occur if the memory stick is physically lost. Untethered drives are most at risk of being physically lost because their lightweight nature allows them to slip out of pockets unnoticed. To protect against physical loss of the device, itís advisable to have the device tethered to something, preferably a keychain. Some devices have lanyard-style tethers, but use these with caution as the lanyard may only tether the drive cap and not the drive itself, which leaves the drive at risk of falling away unnoticed. Drives tethered to a keychain are less likely to be permanently lost because they are attached to another item that the user has presumably already learned not to lose.
Loss of Confidentiality
Perhaps the greatest benefit of the USB memory stick is also its greatest security risk. Because of its convenient small physical size and large logical size compared it predecessor, the floppy disk, more data can find its way to the USB Memory stick. Some of this data is likely to be confidential and becomes a risk if the media is lost. An executive who uses a memory stick to transfer a customer database from his desktop to laptop could potentially subsequently lose the memory stick. If the stick then finds its way into the hands of a competitor, then the company has suffered a much greater loss than simply the replacement cost of the memory stick. In a similar scenario, if a healthcare professional loses a memory stick containing patient records, then there are legal liability issues associated with HIPAA regulations.
There are two primary ways to mitigate the risk of loss of confidential data, mainly avoidance and encryption. With an avoidance strategy, no data is stored on the memory stick that can be considered private. Clearly, this strategy is severely limiting, not the least of which is determining exactly what constitutes private data. An ideal encryption strategy allows any data to be stored on the memory stick but renders the data useless without the required encryption key, which is usually a strong password, but can also be a biometric such as a thumb print. Some USB memory sticks include their own proprietary encryption algrithms and formats, but often the encryption used is either unproven or inadequate, and the memory sticks are more expensive. However, encryption software is available from many vendors that can be used to protect data on the memory stick. One of these, Cryptainer LE for Windows from Cypherix Software is available in a lightweight version, free of charge that will be explored later on
Using Encryption to Safeguard Data on USB Memory Sticks
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