weasel: date=May 2008

A dongle is a small piece of hardware that connects to a computer, and may be portable like a USB Pen. Although earlier use of dongles was to authenticate a piece of software, the word dongle is now widely used to refer to a broadband wireless adaptor.

Electrically the authentication dongles mostly appear as two-interface security tokens with transient data flow that does not interfere with other dongle functions and a pull communication that reads security data from the dongle. Without the dongle, the software will run only in a restricted mode, or not at all. Dongles are used by some proprietary vendors as a form of copy protection or digital rights management, because it is much harder to copy a dongle than to copy the software it authenticates. Despite being hardware, however, dongles are not a complete solution to the trusted client problem.

History

WORDCRAFT was the first program to use a software protection dongle, in 1980. Its dongle was a simple passive device that supplied data to the pins of a Commodore PET's external cassette port in a pre-determined manner. This was possible because the PET cassette port supplied both power and data connections through a proprietary edge connector. It did, however, make the cassette port unusable for its intended purpose.

The two-cubic-inch (32 cm³) resin-potted first generation device was called a "dongle" by the inventor, in the absence of a suitable term. The distributor, Dataview Ltd., then based in Colchester, UK, then went on to produce a derivative dongle, which became their core business.

Dongles rapidly evolved into active devices that contained a serial transceiver (UART) and even a microprocessor to handle transactions with the host. Later versions adopted the USB interface in preference to the serial or parallel interface. Currently, the USB interface is gradually becoming dominant.

Interestingly, modern smart cards present the same feature set as modern dongles. Given this, the dongle market may be overtaken by smart cards, as smart cards are more secure and powerful by design than traditional MCU based dongles. Some dongle vendors are producing one-chip dongles, which combine the smart card and the smart card reader in the same chip. This structure makes a smart card dongle easy and stable.

A 1992 advertisement for Rainbow Technologies (now SafeNet—a dongle vendor in the U.S) claimed the word was derived from the name "Don Gall". Though untrue, this has given rise to an urban myth.

Microcosm Ltd has combined a USB software-protection dongle with a flash drive into a single unit in their Dinkey FD range. This provides an alternative distribution method to the traditional CDROM plus dongle.

Copy protection