Darknet

A darknet (or dark net) is an overlay network that can only be accessed with specific software, configurations, or authorization, often using non-standard and ports. Two typical darknet types are friend-to-friend networks (usually used for file sharing with a peer-to-peer connection) and privacy networks such as Tor.

The reciprocal term for an encrypted darknet is clearnet or surface web when referring to search engine indexable content.

As of 2015^[update], "The Darknet" is often used interchangeably with the dark web due to the quantity of hidden services on Tor's darknet. The term is often inaccurately used interchangeably with the deep web due to Tor's history as a platform that could not be search indexed. Mixing uses of both these terms has been described as inaccurate, with some commentators recommending the terms be used in distinct fashions.

"Darknet" was coined in the 1970s to designate networks that were isolated from ARPANET (which evolved into the Internet), for security purposes. Darknet addresses could receive data from ARPANET but did not appear in the network lists and would not answer pings or other inquiries.

The term gained public acceptance following publication of "The Darknet and the Future of Content Distribution", a 2002 paper by Peter Biddle, Paul England, Marcus Peinado, and Bryan Willman, four employees of Microsoft who argued that the presence of the darknet was the primary hindrance to the development of workable digital rights management (DRM) technologies and made copyright infringement inevitable.

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