Editing Onion routing (section)

{{short description|Technique for anonymous communication over a computer network}}
{{Update|date=March 2017 | inaccurate=yes}}

[[File:Onion diagram.svg|thumb|upright=1.35|In this example onion, the source of the data sends the onion to Router A, which removes a layer of encryption to learn only where to send it next and where it came from (though it does not know if the sender is the origin or just another node). Router A sends it to Router B, which decrypts another layer to learn its next destination. Router B sends it to Router C, which removes the final layer of encryption and transmits the original message to its destination.]]
'''Onion routing''' is a technique for [[anonymity|anonymous]] communication over a [[computer network]]. In an '''onion network''', messages are encapsulated in layers of [[encryption]], analogous to the layers of an [[onion]]. The [[Encryption|encrypted]] data is transmitted through a series of [[network nodes]] called "'''onion routers'''," each of which "peels" away a single layer, revealing the data's next destination. When the final layer is decrypted, the message arrives at its destination. The sender remains anonymous because each intermediary knows only the location of the immediately preceding and following nodes.<ref>Goldschlag D., Reed M., Syverson P. (1999.) [http://www.onion-router.net/Publications/CACM-1999.pdf Onion Routing for Anonymous and Private Internet Connections], Onion Router.</ref> While onion routing provides a high level of security and anonymity, there are methods to break the anonymity of this technique, such as timing analysis.<ref name=":0">{{cite book|last1=Soltani|first1=Ramin|last2=Goeckel|first2=Dennis|last3=Towsley|first3=Don|last4=Houmansadr|first4=Amir|date=2017-11-27|chapter=Towards Provably Invisible Network Flow Fingerprints|arxiv=1711.10079|doi=10.1109/ACSSC.2017.8335179|title=2017 51st Asilomar Conference on Signals, Systems, and Computers|pages=258–262|isbn=978-1-5386-1823-3|s2cid=4943955}}</ref>