Infobox Top level domain

type=Pseudo-domain-style host suffix
status=Not in root, but used by Tor clients, servers, and proxies
intendeduse=To designate a hidden service reachable via Tor
actualuse=Used by Tor users for services in which both provider and user is anonymous and difficult to trace
restrictions=Addresses are "registered" automatically by Tor client when a hidden service is set up
structure=Names are opaque strings such as jv6g2ucbhrjcnwgi.onion, generated from public keys
document= [http://tor.eff.org/cvs/tor/doc/design-paper/tor-design.html Tor design document]
disputepolicy=See [http://tor.eff.org/faq-abuse.html Tor abuse FAQ]
website= [https://www.torproject.org/ www.torproject.org]

.onion is a pseudo-top-level domain host suffix (similar in concept to such endings as .bitnet and .uucp used in earlier times) designating an anonymous hidden service reachable via the Tor network. Such addresses are not actual DNS names, and the .onion TLD is not in the Internet DNS root, but with the appropriate proxy software installed, Internet programs such as Web browsers can access sites with .onion addresses by sending the request through the network of Tor servers. The purpose of using such a system is to make both the information provider and the person accessing the information more difficult to trace, whether by one another, by an intermediate network host, or by an outsider.

Addresses in the .onion pseudo-TLD are opaque, non-meaningful strings which are automatically generated based on a public key when a hidden service is configured.

The "onion" name refers to onion routing, the technique used by Tor to achieve a degree of anonymity.

A few examples of .onion hosts can be found in the main Wikipedia article on Tor, under hidden services.


.exit is a pseudo-top-level domain used by Tor users to indicate on the fly to the Tor software the preferred exit node that should be used while connecting to a service such as a web server, without having to edit the configuration file for Tor ("torrc")

The syntax used with this domain is "hostname" + ".exitnode" + ".exit", so that a user wanting to connect to [http://www.torproject.org/ www.torproject.org] through node "tor26" would have to type " [http://www.torproject.org.tor26.exit/ www.torproject.org.tor26.exit] " in his browser as the URL.

Example uses for this include accessing a site available only to addresses of a certain country or checking if a certain node is working.

Users can also type "exitnode.exit" alone to access the IP address of "exitnode"

External links

* [http://www.torproject.org/docs/tor-hidden-service.html Tor: Hidden Service Configuration Instructions]
* [http://www.torproject.org/svn/trunk/doc/spec/rend-spec.txt Tor Rendezvous Specification]
* [http://oldd6th4cr5spio4.onion Wiki index of .onion resources] available only through Tor

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • ONION — (Heb. בָּצָל), the Allium cepa, one of the earliest cultivated plants. It is mentioned only once in the Bible as one of the vegetables eaten in Egypt for which the Israelites longed when they were in the wilderness (Num. 11:5). Onion growing was… …   Encyclopedia of Judaism

  • Onion — On ion, n. [F. ognon, fr. L. unio oneness, unity, a single large pearl, an onion. See {One}, {Union}.] 1. (Bot.) A liliaceous plant of the genus {Allium} ({Allium cepa}), having a strong flavored bulb and long hollow leaves; also, its bulbous… …   The Collaborative International Dictionary of English

  • .onion — Введение 2004 Тип домена псевдо домен верхнего уровня Статус действующий Регистратор Tor Назначение Обеспечение доступа к анонимным сервисам сети Tor …   Википедия

  • onion — (n.) early 12c., from Anglo Fr. union, O.Fr. oignon (formerly also oingnon), from L. unionem (nom. unio), colloquial rustic Roman for a kind of onion, also pearl (via notion of a string of onions), lit. one, unity; sense connection is the… …   Etymology dictionary

  • onion — [un′yən] n. [ME oynon < OFr oignon < L unio (gen. unionis), oneness, unity, also a kind of single onion: see UNION] 1. a plant (Allium cepa) of the lily family, having an edible bulb with a strong, sharp smell and taste 2. the bulb of this… …   English World dictionary

  • onion — см. Приложение 1 (Allium). (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • onion — onion. См. луки. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • onion — ► NOUN ▪ an edible bulb used as a vegetable, having a pungent taste and smell and composed of several concentric layers. ● know one s onions Cf. ↑know one s onions DERIVATIVES oniony adjective. ORIGIN Old French oignon, from Latin unio …   English terms dictionary

  • Onion — Onions redirects here. For the name and those bearing it, see Onions (surname). This article is about the plants. For other uses, see Onion (disambiguation). Onion Onions Scientific classification …   Wikipedia

  • onion — onionlike, adj. oniony, adj. /un yeuhn/, n. 1. a plant, Allium cepa, of the amaryllis family, having an edible, succulent, pungent bulb. 2. any of certain similar plants. 3. the bulb of the onion plant. 4. the flavor or odor of this bulb. 5.… …   Universalium