Sneakernet

Sneakernet is an informal term describing the transfer of electronic information by physically moving media such as magnetic tape, floppy disks, compact discs, USB flash drives or external hard drives from one computer to another; rather than transmitting the information over a computer network.

The term, a tongue-in-cheek play on net(work) as in Internet or Ethernet, refers to the wearing of sneakers as the transport mechanism for the data.

Sneakernets, also known as trainnets or pigeonets, are in use throughout the computer world. Sneakernet may be used when computer networks are prohibitively expensive for the owner to maintain, in high-security environments where manual inspection (for re-classification of information) is necessary, where information needs to be shared between networks with different levels of security clearance, when data transfer is impractical due to bandwidth limitations, when a guest laptop is incompatible with the local network, or simply when two computers are not powered up at the same time or lack the correct interconnecting cabling. Because sneakernets take advantage of physical media, different security measures must be taken into account for the transfer of sensitive information.

This form of data transfer is also used for peer-to-peer (or friend-to-friend) file sharing and has grown in popularity in metropolitan areas and college communities. The ease of this system has been facilitated by the availability of USB external hard drives, USB flash drives and portable music players.

The United States Postal Service also offers a Media Mail service for compact discs, among other items. This provides a viable mode of transport for long distance sneakernet use. In fact, when mailing a sufficiently large hard drive or a spindle of DVDs, the throughput (amount of data per unit time) may compete favorably with other methods of data transfer.

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