Dark web

The dark web is a portion of the internet intentionally hidden from standard search engines and reached through specialized software or configurations. Many dark-web services are designed to provide anonymity.

Tor: Tor is a network that routes internet traffic through relays to reduce the ability to trace its source and destination. Tor is the best-known network for reaching dark-web services.
SecureDrop: SecureDrop is an open-source whistleblower submission system used by news organizations to receive documents securely. It uses anonymity technologies to connect sources with journalists.
Surface web: The surface web consists of publicly accessible web pages indexed by standard search engines. Its searchable pages contrast with intentionally unindexed dark-web services.
Online anonymity: Online anonymity is the condition of using digital services without readily linking activity to a real-world identity. Dark-web systems are designed to strengthen anonymity, but cannot guarantee it.
Traffic analysis: Traffic analysis infers communication patterns from timing, volume, or direction of network traffic, even when content is encrypted. Observers may correlate traffic patterns to weaken anonymity without decrypting messages.
Onion service: An onion service is a network service reachable through Tor without exposing its server’s IP address to clients. Onion services are the hidden sites most commonly associated with the dark web.
Whistleblowing: Whistleblowing is the disclosure of information about wrongdoing within an organization or institution. Anonymous channels can help sources disclose material while limiting exposure.
Deep web: The deep web consists of online content not indexed by standard search engines, including private databases and account pages. The dark web is a smaller portion of the broader deep web.
Threat model: A threat model identifies an asset, potential attackers, their capabilities, and the protections needed against them. Anonymity depends on which observers and technical failures a user must withstand.
Sybil attack: A Sybil attack occurs when one actor creates many identities to gain disproportionate influence in a network. Control of numerous relays could threaten anonymity-network security.

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CybercrimeRelated: Some illicit marketplaces and forums operate there, though the dark web also has lawful uses.