Sneakernet

Sneakernet, also called sneaker net, is an informal term for the transfer of electronic information by physically moving media such as magnetic tape, floppy disks, optical discs, USB flash drives or external hard drives between computers, rather than transmitting it over a computer network. Sneakernets enable data transfer through physical means and offer a solution in the presence of network connections that lack reliability; however, a consequence of this physical transfer is high latency. The term, a tongue-in-cheek play on net(work) as in Internet or Ethernet, refers to walking in sneakers as the transport mechanism. Alternative terms may be floppy net, train net, or pigeon net.

Sneakernets are in use throughout the computer universe. A 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 particular system is simply incompatible with the local network, unable to be connected, or when two systems are not on the same network at the same time. Because sneakernets take advantage of physical media, security measures used for the transfer of sensitive information are respectively physical.

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 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 media with sufficiently high data density such as high capacity hard drives, the throughput (data transferred per unit of time) as well as the cost per unit of data transferred may compete favorably with networked methods of data transfer.

A quantum version of sneakernet was proposed in a paper by Simon Devitt and collaborators in 2016.

In 2021 Taliban-governed Afghanistan, "computer kars" distribute Internet-derived content by hand: "Movies, music, mobile applications, iOS updates, and naughty videos. Also creating Apple IDs and social media accounts, and backing up and unlocking phones and recovering data." The kars collectively maintain an archive of hundreds of terabytes of data. Four terabytes of the latest Indian or American movies or Turkish TV dramas, dubbed in the Afghan national languages Dari and Pashto reportedly wholesale for about 800 afghanis, or nine US dollars, while the retail price of five gigabytes of content is 100 afghanis, or one US dollar. Kars report that their earnings have dropped 90% under Taliban rule.

When Australia joined Usenet in 1983, it received articles via tapes sent from the United States to the University of Sydney, which disseminated data to dozens of other computers on the country's Unix network.

The Rigsum Sherig Collection project uses a sneakernet to distribute offline educational resources, including Kiwix and Khan Academy on a Stick, to hundreds of schools and other educational institutions in the Kingdom of Bhutan. Many of the schools in Bhutan have computers or IT labs, but no Internet connection (or a very slow one). The sneakernet, facilitated by teachers, distributes about 25 GB of free, open-source educational software to the schools, often using external hard disks.