The term sneakernet may be used in any case where physical media is used to transfer data between computers, rather than using an electronic network. This can be as simple as running actual paper files from one side of a business or academic compound to the other, or as involved as sending large amounts of data via airplane or other methods of conveyance. Experiments have even been done with carrier pigeons, with the birds carrying data via universal serial bus (USB) memory modules strapped to their legs. Some purposes of a sneakernet may include securely transferring sensitive materials, moving large amounts of information in a timely manner, or even circumventing the lack of an electronic networking infrastructure.
One of the simplest uses of a sneakernet might be moving sensitive documents via physical media. This type of transfer generally doesn't take into account any of the other possible benefits of a sneakernet, as its main purpose is to bypass security concerns involved with transferring data via a network. This usage may involve actually delivering the information via physical media, or sending encrypted data via an electronic network and then using a courier to deliver the encryption key. Either of these may add an extra layer of security to the transfer of important documents or code.
The idea of a sneakernet has been used in academic contexts as an example that helps demonstrate a relationship between bandwidth and latency. Bandwidth refers to the rate at which a system transfers information, while latency is the time it takes for a single unit, or packet, of data to reach its destination. Electronic networks typically seek to achieve low levels of latency, while a sneakernet can exhibit very high latency but demonstrate a potentially high bandwidth as well. While it may take many hours for data delivered via a vehicle like a car or a plane to arrive, that vehicle can carry a sufficiently large amount of data that the throughput of an electronic network in the same period of time may actually be met or exceeded.
This idea has real world applications in cases where an electronic network is either lacking or nonexistent. In some cases, telescope or other monitoring types of installations must transfer large amounts of data to off-site facilities. When the networking infrastructure isn't there for efficient information transfer, airplanes may be used to move information via hard disc drives (HDDs) or other high capacity physical media. While the latency of such a transfer is measured in hours, this is an example where a sneakernet can achieve an acceptable throughput.
