Anonymous P2P
Encyclopedia
An anonymous P2P communication system is a peer-to-peer
distributed application in which the nodes or participants are anonymous
or pseudonymous
. Anonymity of participants is usually achieved by special routing overlay network
s that hide the physical location of each node from other participants.
Interest in anonymous P2P systems has increased in recent years for many reasons, ranging from the desire to share files without revealing one's network identity and risking litigation to distrust in governments, concerns over mass surveillance
and data retention
, and lawsuits against blog
gers.
P2P users who desire anonymity usually do so as they do not wish to be identified as a publisher (sender), or reader (receiver), of information. Common reasons include:
A particularly open view on legal and illegal content is given in The Philosophy Behind Freenet.
Governments are also interested in anonymous P2P technology. The United States
Navy
funded the original onion routing
research that led to the development of the Tor
network, which was later funded by the Electronic Frontier Foundation
and is now developed by the non-profit organization The Tor Project, Inc.
, libel
, the exchange of illegal pornography
, the unauthorized copying of copyrighted works, or the planning of criminal activities. Critics of anonymous P2P systems hold that the advantages offered by such systems do not outweigh these disadvantages, and that other communication channels are already sufficient for unpopular speech.
Some proponents of anonymous P2P systems believe that all restrictions on free speech serve authoritarian interests. Others argue that information itself is ethically neutral, and that it is the people acting upon the information that can be good or evil. Perceptions of good and evil can also change (see moral panic
); for example, if anonymous peer-to-peer networks had existed in the 1950s or 1960s, they might have been targeted for carrying information about civil rights
or anarchism
.
Easily accessible anonymous P2P networks are seen by some as a democratization of encryption
technology, giving the general populace access to secure communications channels already used by governments. Supporters of this view, such as Phil Zimmermann
, argue that anti-surveillance technologies help to equalize power between governments and their people, which is the actual reason for banning them. Pilger
opines that monitoring of the populace helps to contain threats to the "consensual view of established authority" or threats to the continuity of power structures and privilege.
, especially on controversial subjects, is difficult or impossible unless individuals can speak anonymously. If anonymity is not possible, one could be subjected to threats or reprisals for voicing an unpopular view. This is one reason why voting is done by secret ballot in many democracies. Controversial information which a party wants to keep hidden, such as details about corruption issues, is often published or leaked anonymously.
While anonymous blogging is possible on the non-anonymous internet to some degree too, a provider hosting the blog in question might be forced to disclose the blogger's IP address (as in the case of Google revealing an anonymous blogger's identity). Anonymous networks provide a better degree of anonymity. Flogs in Freenet
, Syndie
and other blogging tools in I2P
and Osiris sps
are some examples of anonymous blogging technologies.
One argument for anonymous blogging is a delicate nature of work situation. Sometimes a blogger writing under his/her real name faces a choice between either staying silent or causing a harm to himself, his colleagues or the company he works for.
Risk of lawsuits is another reason. Some bloggers have faced multi-million dollar lawsuits that were later dropped completely; anonymous blogging provides protection against such risks.
like "example.com" is a key to accessing information. The censorship of the Wikileaks website shows that domain names are extremely vulnerable to censorship. Some domain registrars have suspended customers' domain names even in the absence of a court order.
For the affected customer, blocking of a domain name is a far bigger problem than a registrar refusing to provide a service; typically, the registrar keeps full control over the domain names in question.
In the case of a European travel agency, more than 80 .com websites were shut down without any court process and held by the registrar since then. The travel agency had to rebuild the sites under the .net top-level domain
instead.
Anonymous networks, on the other hand, do not rely on domain name registrar
s. For example, Freenet
and I2P
implement censorship-resistant URLs based on public-key cryptography
: only a person having the correct private key is able to update the URL or take it down.
For example, most current phone systems transmit caller ID information by default to the called party (although this can be disabled either for a single call or for all calls). If a person calls to make an inquiry about a product or the time of a movie, the party called has a record of the calling phone number, and may be able to obtain the name, address and other information about the caller. This information is not available about someone who walks into a store and makes a similar inquiry.
According to law professor Daniel J. Solove
, such effects "harm society because, among other things, they reduce the range of viewpoints being expressed and the degree of freedom with which to engage in political activity."
, and certain types of content. Other material is legal to possess but not to distribute; for example, copyright and software patent
laws may forbid its distribution. These laws are difficult or impossible to enforce in anonymous P2P networks.
collection. However, any transfer of physical goods between two parties could compromise anonymity.
Some argue that conventional cash
provides a similar kind of anonymity, and that existing laws are adequate to combat crimes like tax evasion
that might result from the use of anonymous cash, whether online or offline.
: instead of being identified by their IP address
es, nodes are identified by pseudonyms such as cryptographic keys. For example, each node in the MUTE
network has an overlay address that is derived from its public key
. This overlay address functions as a pseudonym for the node, allowing messages to be addressed to it. In Freenet
, on the other hand, messages are routed using keys that identify specific pieces of data rather than specific nodes; the nodes themselves are anonymous.
The term anonymous is used to describe both kinds of network because it is difficult—if not impossible—to determine whether a node that sends a message originated the message or is simply forwarding it on behalf of another node. Every node in an anonymous P2P network acts as a universal sender and universal receiver to maintain anonymity. If a node was only a receiver and did not send, then neighbouring nodes would know that the information it was requesting was for itself only, removing any plausible deniability
that it was the recipient (and consumer) of the information. Thus, in order to remain anonymous, nodes must ferry information for others on the network.
and distributed denial-of-service attack
s. Such attacks may require different solutions in anonymous networks. For example, blacklisting of originator network addresses does not work because anonymous networks conceal this information. These networks are more vulnerable to DoS attacks as well due to the smaller bandwidth, as has been shown in examples on the Tor
network.
A conspiracy to attack an anonymous network could be considered criminal computer hacking, though the nature of the network makes this impossible to prosecute without compromising the anonymity of data in the network.
) network type. This describes how a node on the network selects peer nodes:
Some networks like Freenet
support both network types simultaneously (a node can have some manually added darknet peer nodes and some automatically selected opennet peers) .
In a friend-to-friend (or F2F) network, users only make direct connections with people they know. Many F2F networks support indirect anonymous or pseudonymous communication between users who do not know or trust one another. For example, a node in a friend-to-friend overlay can automatically forward a file (or a request for a file) anonymously between two "friends", without telling either of them the other's name or IP address. These "friends" can in turn forward the same file (or request) to their own "friends", and so on.
Users in a friend-to-friend network cannot find out who else is participating beyond their own circle of friends, so F2F networks can grow in size without compromising their users' anonymity.
Some friend-to-friend
networks allow the user to control what kind of files can be exchanged with "friends" within the node, in order to stop them from exchanging files that user disapproves of.
Advantages and disadvantages of opennet compared to darknet are disputed, see friend-to-friend
article for summary.
networks are P2P networks that only allow some mutually trusted computers to share files. This can be achieved by using a central server or hub to authenticate clients, in which case the functionality is similar to a private FTP
server, but with files transferred directly between the clients. Alternatively, users can exchange passwords or keys with their friends to form a decentralized network.
networks are P2P networks that allows users only to make direct connections with people they know. Passwords or digital signatures can be used for authentication. Examples include Retroshare
and OneSwarm
.
; unlike fixed Internet connections, users don't need to sign up with an ISP to participate in such a network, and are only identifiable through their hardware. Even if a government were to outlaw the use of wireless P2P software, it would be difficult to enforce such a ban without a considerable infringement of personal freedoms. Alternatively, the government could outlaw the purchase of the wireless hardware itself. Protocols for wireless mesh networks are Optimized Link State Routing Protocol
(OLSR) and the follow-up protocol B.A.T.M.A.N.
, which is designed for decentralized auto-IP assignment. See also Netsukuku
.
Peer-to-peer
Peer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads among peers. Peers are equally privileged, equipotent participants in the application...
distributed application in which the nodes or participants are anonymous
Anonymity
Anonymity is derived from the Greek word ἀνωνυμία, anonymia, meaning "without a name" or "namelessness". In colloquial use, anonymity typically refers to the state of an individual's personal identity, or personally identifiable information, being publicly unknown.There are many reasons why a...
or pseudonymous
Pseudonymity
Pseudonymity is a word derived from pseudonym, meaning 'false name', and anonymity, meaning unknown or undeclared source, describing a state of disguised identity. The pseudonym identifies a holder, that is, one or more human beings who possess but do not disclose their true names...
. Anonymity of participants is usually achieved by special routing overlay network
Overlay network
An overlay network is a computer network which is built on the top of another network. Nodes in the overlay can be thought of as being connected by virtual or logical links, each of which corresponds to a path, perhaps through many physical links, in the underlying network...
s that hide the physical location of each node from other participants.
Interest in anonymous P2P systems has increased in recent years for many reasons, ranging from the desire to share files without revealing one's network identity and risking litigation to distrust in governments, concerns over mass surveillance
Mass surveillance
Mass surveillance is the pervasive surveillance of an entire population, or a substantial fraction thereof.Modern governments today commonly perform mass surveillance of their citizens, explaining that they believe that it is necessary to protect them from dangerous groups such as terrorists,...
and data retention
Data retention
Data retention defines the policies of persistent data and records management for meeting legal and business data archival requirements. A data retention policy weighs legal and privacy concerns against economics and need to know concerns to determine both the retention time, archival rules, data...
, and lawsuits against blog
Blog
A blog is a type of website or part of a website supposed to be updated with new content from time to time. Blogs are usually maintained by an individual with regular entries of commentary, descriptions of events, or other material such as graphics or video. Entries are commonly displayed in...
gers.
Motivation for anonymity
There are many reasons to use anonymous P2P technology; most of them are generic to all forms of online anonymity.P2P users who desire anonymity usually do so as they do not wish to be identified as a publisher (sender), or reader (receiver), of information. Common reasons include:
- The material or its distribution is illegal or incriminating
- Material is legal but socially deplored, embarrassing or problematic in the individual's social world (for example, anonymity is seen as a key requirement for organizations like Alcoholics AnonymousAlcoholics AnonymousAlcoholics Anonymous is an international mutual aid movement which says its "primary purpose is to stay sober and help other alcoholics achieve sobriety." Now claiming more than 2 million members, AA was founded in 1935 by Bill Wilson and Dr. Bob Smith in Akron, Ohio...
) - Fear of retribution (against whistleblowers, unofficial leaks, and activists who do not believe in restrictions on information or knowledge)
- Censorship at the local, organizational, or national level
- Personal privacy preferences such as preventing trackingWeb visitor trackingWeb visitor tracking is the analysis of visitor behaviour on a website. Analysis of an individual visitor's behaviour may be used to provide that visitor with options or content that relates to their implied preferences; either during a visit or in the future...
or datamining activities
A particularly open view on legal and illegal content is given in The Philosophy Behind Freenet.
Governments are also interested in anonymous P2P technology. The United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
Navy
Navy
A navy is the branch of a nation's armed forces principally designated for naval and amphibious warfare; namely, lake- or ocean-borne combat operations and related functions...
funded the original onion routing
Onion routing
Onion routing is a technique for anonymous communication over a computer network. Messages are repeatedly encrypted and then sent through several network nodes called onion routers. Like someone unpeeling an onion, each onion router removes a layer of encryption to uncover routing instructions, and...
research that led to the development of the Tor
Tor (anonymity network)
Tor is a system intended to enable online anonymity. Tor client software routes Internet traffic through a worldwide volunteer network of servers in order to conceal a user's location or usage from someone conducting network surveillance or traffic analysis...
network, which was later funded by the Electronic Frontier Foundation
Electronic Frontier Foundation
The Electronic Frontier Foundation is an international non-profit digital rights advocacy and legal organization based in the United States...
and is now developed by the non-profit organization The Tor Project, Inc.
General
While anonymous P2P systems may support the protection of unpopular speech, they may also protect illegal activities not protected under some free speech laws, such as fraudFraud
In criminal law, a fraud is an intentional deception made for personal gain or to damage another individual; the related adjective is fraudulent. The specific legal definition varies by legal jurisdiction. Fraud is a crime, and also a civil law violation...
, libel
Slander and libel
Defamation—also called calumny, vilification, traducement, slander , and libel —is the communication of a statement that makes a claim, expressly stated or implied to be factual, that may give an individual, business, product, group, government, or nation a negative image...
, the exchange of illegal pornography
Pornography
Pornography or porn is the explicit portrayal of sexual subject matter for the purposes of sexual arousal and erotic satisfaction.Pornography may use any of a variety of media, ranging from books, magazines, postcards, photos, sculpture, drawing, painting, animation, sound recording, film, video,...
, the unauthorized copying of copyrighted works, or the planning of criminal activities. Critics of anonymous P2P systems hold that the advantages offered by such systems do not outweigh these disadvantages, and that other communication channels are already sufficient for unpopular speech.
Some proponents of anonymous P2P systems believe that all restrictions on free speech serve authoritarian interests. Others argue that information itself is ethically neutral, and that it is the people acting upon the information that can be good or evil. Perceptions of good and evil can also change (see moral panic
Moral panic
A moral panic is the intensity of feeling expressed in a population about an issue that appears to threaten the social order. According to Stanley Cohen, author of Folk Devils and Moral Panics and credited creator of the term, a moral panic occurs when "[a] condition, episode, person or group of...
); for example, if anonymous peer-to-peer networks had existed in the 1950s or 1960s, they might have been targeted for carrying information about civil rights
Civil rights
Civil and political rights are a class of rights that protect individuals' freedom from unwarranted infringement by governments and private organizations, and ensure one's ability to participate in the civil and political life of the state without discrimination or repression.Civil rights include...
or anarchism
Anarchism
Anarchism is generally defined as the political philosophy which holds the state to be undesirable, unnecessary, and harmful, or alternatively as opposing authority in the conduct of human relations...
.
Easily accessible anonymous P2P networks are seen by some as a democratization of encryption
Encryption
In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...
technology, giving the general populace access to secure communications channels already used by governments. Supporters of this view, such as Phil Zimmermann
Phil Zimmermann
Philip R. "Phil" Zimmermann Jr. is the creator of Pretty Good Privacy , the most widely used email encryption software in the world. He is also known for his work in VoIP encryption protocols, notably ZRTP and Zfone....
, argue that anti-surveillance technologies help to equalize power between governments and their people, which is the actual reason for banning them. Pilger
John Pilger
John Richard Pilger is an Australian journalist and documentary maker, based in London. He has twice won Britain's Journalist of the Year Award, and his documentaries have received academy awards in Britain and the US....
opines that monitoring of the populace helps to contain threats to the "consensual view of established authority" or threats to the continuity of power structures and privilege.
Freedom of speech
Some claim that true freedom of speechFreedom of speech
Freedom of speech is the freedom to speak freely without censorship. The term freedom of expression is sometimes used synonymously, but includes any act of seeking, receiving and imparting information or ideas, regardless of the medium used...
, especially on controversial subjects, is difficult or impossible unless individuals can speak anonymously. If anonymity is not possible, one could be subjected to threats or reprisals for voicing an unpopular view. This is one reason why voting is done by secret ballot in many democracies. Controversial information which a party wants to keep hidden, such as details about corruption issues, is often published or leaked anonymously.
Anonymous blogging
Anonymous blogging is one widespread use of anonymous networks.While anonymous blogging is possible on the non-anonymous internet to some degree too, a provider hosting the blog in question might be forced to disclose the blogger's IP address (as in the case of Google revealing an anonymous blogger's identity). Anonymous networks provide a better degree of anonymity. Flogs in Freenet
Freenet
Freenet is a decentralized, censorship-resistant distributed data store originally designed by Ian Clarke. According to Clarke, Freenet aims to provide freedom of speech through a peer-to-peer network with strong protection of anonymity; as part of supporting its users' freedom, Freenet is free and...
, Syndie
Syndie
Syndie is an open source cross-platform computer application to syndicate data over a variety of anonymous and non-anonymous computer networks.-Features:...
and other blogging tools in I2P
I2P
I2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
and Osiris sps
Osiris (Serverless Portal System)
Osiris Serverless Portal System is a freeware program used to create web portals distributed via peer-to-peer networking and autonomous from centralized servers...
are some examples of anonymous blogging technologies.
One argument for anonymous blogging is a delicate nature of work situation. Sometimes a blogger writing under his/her real name faces a choice between either staying silent or causing a harm to himself, his colleagues or the company he works for.
Risk of lawsuits is another reason. Some bloggers have faced multi-million dollar lawsuits that were later dropped completely; anonymous blogging provides protection against such risks.
Censorship via Internet domain names
On the non-anonymous Internet, a domain nameDomain name
A domain name is an identification string that defines a realm of administrative autonomy, authority, or control in the Internet. Domain names are formed by the rules and procedures of the Domain Name System ....
like "example.com" is a key to accessing information. The censorship of the Wikileaks website shows that domain names are extremely vulnerable to censorship. Some domain registrars have suspended customers' domain names even in the absence of a court order.
For the affected customer, blocking of a domain name is a far bigger problem than a registrar refusing to provide a service; typically, the registrar keeps full control over the domain names in question.
In the case of a European travel agency, more than 80 .com websites were shut down without any court process and held by the registrar since then. The travel agency had to rebuild the sites under the .net top-level domain
Top-level domain
A top-level domain is one of the domains at the highest level in the hierarchical Domain Name System of the Internet. The top-level domain names are installed in the root zone of the name space. For all domains in lower levels, it is the last part of the domain name, that is, the last label of a...
instead.
Anonymous networks, on the other hand, do not rely on domain name registrar
Domain name registrar
A domain name registrar is an organization or commercial entity, accredited by both ICANN and generic top-level domain registry to sell gTLDs and/or by a country code top-level domain registry to sell ccTLDs; to manage the reservation of Internet domain names in accordance with the guidelines of...
s. For example, Freenet
Freenet
Freenet is a decentralized, censorship-resistant distributed data store originally designed by Ian Clarke. According to Clarke, Freenet aims to provide freedom of speech through a peer-to-peer network with strong protection of anonymity; as part of supporting its users' freedom, Freenet is free and...
and I2P
I2P
I2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
implement censorship-resistant URLs based on public-key cryptography
Public-key cryptography
Public-key cryptography refers to a cryptographic system requiring two separate keys, one to lock or encrypt the plaintext, and one to unlock or decrypt the cyphertext. Neither key will do both functions. One of these keys is published or public and the other is kept private...
: only a person having the correct private key is able to update the URL or take it down.
Control over online tracking
Anonymous P2P also has value in normal daily communication. When communication is anonymous, the decision to reveal the identities of the communicating parties is left up to the parties involved and is not available to a third party. Often there is no need or desire by the communicating parties to reveal their identities. As a matter of personal freedom, many people do not want processes in place by default which supply unnecessary data. In some cases such data could be compiled into histories of their activities.For example, most current phone systems transmit caller ID information by default to the called party (although this can be disabled either for a single call or for all calls). If a person calls to make an inquiry about a product or the time of a movie, the party called has a record of the calling phone number, and may be able to obtain the name, address and other information about the caller. This information is not available about someone who walks into a store and makes a similar inquiry.
Effects of surveillance on lawful activity
Online surveillance, such as recording and retaining details of web and e-mail traffic, may have effects on lawful activities. People may be deterred from accessing or communicating legal information because they know of possible surveillance and believe that such communication may be seen as suspicious.According to law professor Daniel J. Solove
Daniel J. Solove
Daniel J. Solove is a professor of law at the George Washington University Law School. He is well known for his academic work on privacy and for popular books on how privacy relates with information technology...
, such effects "harm society because, among other things, they reduce the range of viewpoints being expressed and the degree of freedom with which to engage in political activity."
Access to censored and copyrighted material
Most countries ban or censor the publication of certain books and moviesBanned films
For nearly the entire history of film production, certain films have been banned by film censorship or review organizations for political or moral reasons...
, and certain types of content. Other material is legal to possess but not to distribute; for example, copyright and software patent
Software patent
Software patent does not have a universally accepted definition. One definition suggested by the Foundation for a Free Information Infrastructure is that a software patent is a "patent on any performance of a computer realised by means of a computer program".In 2005, the European Patent Office...
laws may forbid its distribution. These laws are difficult or impossible to enforce in anonymous P2P networks.
Anonymous online money
With anonymous money, it becomes possible to arrange anonymous markets where one can buy and sell just about anything anonymously. Anonymous money could be used to avoid taxTax
To tax is to impose a financial charge or other levy upon a taxpayer by a state or the functional equivalent of a state such that failure to pay is punishable by law. Taxes are also imposed by many subnational entities...
collection. However, any transfer of physical goods between two parties could compromise anonymity.
Some argue that conventional cash
Cash
In common language cash refers to money in the physical form of currency, such as banknotes and coins.In bookkeeping and finance, cash refers to current assets comprising currency or currency equivalents that can be accessed immediately or near-immediately...
provides a similar kind of anonymity, and that existing laws are adequate to combat crimes like tax evasion
Tax evasion
Tax evasion is the general term for efforts by individuals, corporations, trusts and other entities to evade taxes by illegal means. Tax evasion usually entails taxpayers deliberately misrepresenting or concealing the true state of their affairs to the tax authorities to reduce their tax liability,...
that might result from the use of anonymous cash, whether online or offline.
Anonymity and pseudonymity
Some of the networks commonly referred to as "anonymous P2P" are truly anonymous, in the sense that network nodes carry no identifiers. Others are actually pseudonymousPseudonymity
Pseudonymity is a word derived from pseudonym, meaning 'false name', and anonymity, meaning unknown or undeclared source, describing a state of disguised identity. The pseudonym identifies a holder, that is, one or more human beings who possess but do not disclose their true names...
: instead of being identified by their IP address
IP address
An Internet Protocol address is a numerical label assigned to each device participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing...
es, nodes are identified by pseudonyms such as cryptographic keys. For example, each node in the MUTE
MUTE
The MUTE Network is an unmaintained peer-to-peer file sharing network developed with anonymity in mind. The MUTE client is open source software released under the Public domain and includes support for the Linux, Mac OS X and Microsoft Windows computer operating systems.-History of MUTE:MUTE was...
network has an overlay address that is derived from its public key
Public-key cryptography
Public-key cryptography refers to a cryptographic system requiring two separate keys, one to lock or encrypt the plaintext, and one to unlock or decrypt the cyphertext. Neither key will do both functions. One of these keys is published or public and the other is kept private...
. This overlay address functions as a pseudonym for the node, allowing messages to be addressed to it. In Freenet
Freenet
Freenet is a decentralized, censorship-resistant distributed data store originally designed by Ian Clarke. According to Clarke, Freenet aims to provide freedom of speech through a peer-to-peer network with strong protection of anonymity; as part of supporting its users' freedom, Freenet is free and...
, on the other hand, messages are routed using keys that identify specific pieces of data rather than specific nodes; the nodes themselves are anonymous.
The term anonymous is used to describe both kinds of network because it is difficult—if not impossible—to determine whether a node that sends a message originated the message or is simply forwarding it on behalf of another node. Every node in an anonymous P2P network acts as a universal sender and universal receiver to maintain anonymity. If a node was only a receiver and did not send, then neighbouring nodes would know that the information it was requesting was for itself only, removing any plausible deniability
Plausible deniability
Plausible deniability is, at root, credible ability to deny a fact or allegation, or to deny previous knowledge of a fact. The term most often refers to the denial of blame in chains of command, where upper rungs quarantine the blame to the lower rungs, and the lower rungs are often inaccessible,...
that it was the recipient (and consumer) of the information. Thus, in order to remain anonymous, nodes must ferry information for others on the network.
Spam and DoS attacks in anonymous networks
Originally, anonymous networks were operated by small and friendly communities of developers. As interest in anonymous P2P increased and the user base grew, malicious users inevitably appeared and tried different attacks. This is similar to the Internet, where widespread use has been followed by waves of spamSpam (electronic)
Spam is the use of electronic messaging systems to send unsolicited bulk messages indiscriminately...
and distributed denial-of-service attack
Denial-of-service attack
A denial-of-service attack or distributed denial-of-service attack is an attempt to make a computer resource unavailable to its intended users...
s. Such attacks may require different solutions in anonymous networks. For example, blacklisting of originator network addresses does not work because anonymous networks conceal this information. These networks are more vulnerable to DoS attacks as well due to the smaller bandwidth, as has been shown in examples on the Tor
Tor (anonymity network)
Tor is a system intended to enable online anonymity. Tor client software routes Internet traffic through a worldwide volunteer network of servers in order to conceal a user's location or usage from someone conducting network surveillance or traffic analysis...
network.
A conspiracy to attack an anonymous network could be considered criminal computer hacking, though the nature of the network makes this impossible to prosecute without compromising the anonymity of data in the network.
Opennet and darknet network types
Like conventional P2P networks, anonymous P2P networks can implement either opennet or darknet (often named friend-to-friendFriend-to-friend
A friend-to-friend computer network is a type of peer-to-peer network in which users only make direct connections with people they know. Passwords or digital signatures can be used for authentication....
) network type. This describes how a node on the network selects peer nodes:
- In opennet network, peer nodes are discovered automatically. There is no configuration required but little control available over which nodes become peers.
- In a darknet network, users manually establish connections with nodes run by people they know. Darknet typically needs more effort to set up but a node only has trusted nodes as peers.
Some networks like Freenet
Freenet
Freenet is a decentralized, censorship-resistant distributed data store originally designed by Ian Clarke. According to Clarke, Freenet aims to provide freedom of speech through a peer-to-peer network with strong protection of anonymity; as part of supporting its users' freedom, Freenet is free and...
support both network types simultaneously (a node can have some manually added darknet peer nodes and some automatically selected opennet peers) .
In a friend-to-friend (or F2F) network, users only make direct connections with people they know. Many F2F networks support indirect anonymous or pseudonymous communication between users who do not know or trust one another. For example, a node in a friend-to-friend overlay can automatically forward a file (or a request for a file) anonymously between two "friends", without telling either of them the other's name or IP address. These "friends" can in turn forward the same file (or request) to their own "friends", and so on.
Users in a friend-to-friend network cannot find out who else is participating beyond their own circle of friends, so F2F networks can grow in size without compromising their users' anonymity.
Some friend-to-friend
Friend-to-friend
A friend-to-friend computer network is a type of peer-to-peer network in which users only make direct connections with people they know. Passwords or digital signatures can be used for authentication....
networks allow the user to control what kind of files can be exchanged with "friends" within the node, in order to stop them from exchanging files that user disapproves of.
Advantages and disadvantages of opennet compared to darknet are disputed, see friend-to-friend
Friend-to-friend
A friend-to-friend computer network is a type of peer-to-peer network in which users only make direct connections with people they know. Passwords or digital signatures can be used for authentication....
article for summary.
Public P2P clients
- Bunzilla - file sharing.
- Calypso - (formerly Kommute) successor to Mute
- FreenetFreenetFreenet is a decentralized, censorship-resistant distributed data store originally designed by Ian Clarke. According to Clarke, Freenet aims to provide freedom of speech through a peer-to-peer network with strong protection of anonymity; as part of supporting its users' freedom, Freenet is free and...
- a censorship-resistant distributed file systemDistributed file systemNetwork file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...
for anonymous publishing (open source, written in Java) - GNUnetGNUnetGNUnet is a free software framework for decentralized, peer-to-peer networking. The framework offers link encryption, peer discovery and resource allocation....
- P2P framework, includes anonymous file sharing as its primary application (GNU ProjectGNU ProjectThe GNU Project is a free software, mass collaboration project, announced on September 27, 1983, by Richard Stallman at MIT. It initiated GNU operating system development in January, 1984...
, written in C) - I2PI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
- a decentralized (overlay) network for strong anonymity and end-to-end encryption, with many applications (P2P, browsing, distributed anonymous e-mail, instant messaging, IRC, ...) running on top of it (free/open source, platform-independent) - I2P-Bote an anonymous, secure (end-to-end encrypted), serverless mail application with remailer functionality for the I2PI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
network - I2P-Messenger an anonymous, secure (end-to-end encrypted), serverless instant messenger for the I2PI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
network - I2PSnark - an anonymous BitTorrent client for the I2PI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
network - I2P-Tahoe-LAFSI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
- a censorship-resistant distributed file systemDistributed file systemNetwork file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...
for anonymous publishing and file sharing (open source, written in Python) - iMuleIMuleiMule is a free open source anonymous P2P file sharing software which connects through the anonymous I2P network and the Kad network.- Description :...
- an eMule port running under I2P network (includes built-in I2P router) - NetsukukuNetsukukuNetsukuku is the name of an experimental peer-to-peer routing system, developed by the in 2006, created to build up a distributed network, anonymous and censorship-free, fully independent but not necessarily separated from the Internet, without the support of any server, ISP and no central...
- a peer-to-peer routing system aiming to build a free and independent Internet - NodezillaNodezillaNodezilla is a peer-to-peer network software written in C++ and Java , and the GUI part is released under the GNU General Public License. It attempts to provide anonymity.-Features:...
- an anonymizing, closed source network layer upon which applications can be built (written in C++ and Java) - OneSwarmOneSwarmOneSwarm is a privacy-preserving P2P client developed at the University of Washington. Although backward compatible with traditional BitTorrent clients, OneSwarm also includes new features designed to protect user privacy when sharing data among friends through creating a distributed darknet,...
- A backwards compatible BitTorrent client with privacy-preserving sharing options, aims to create a large F2F network. - OFF SystemOwner free filing systemThe Owner-Free File System is a peer-to-peer distributed file system in which all shared files are represented by randomized multi-used data blocks. Instead of anonymizing the network, the data blocks are anonymized and therefore, only data garbage is ever exchanged and stored and no forwarding...
- a P2P distributed file systemDistributed file systemNetwork file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...
through which all shared files are represented by randomized data blocks - OmemoOmemoOmemo is an open source social storage platform, in which users anonymously share files on a part of their hard disks. It has been developed by Pablo Soto, who is also creator of Blubster.Omemo uses a ring-shaped DHT based on Chord...
- an open source social storage platform (P2P virtual hard drive) - Osiris spsOsiris (Serverless Portal System)Osiris Serverless Portal System is a freeware program used to create web portals distributed via peer-to-peer networking and autonomous from centralized servers...
- an anonymous and distributed web portals creator. - Perfect DarkPerfect Dark (P2P)is a Japanese peer-to-peer file-sharing application designed for use with Microsoft Windows . It was launched in 2006, its author is known by the pseudonym . Perfect Dark was developed with the intention for it to be the successor to both Winny and Share...
- a P2P client which relies on a mixnetMix networkDigital mixes were invented by David Chaum in 1981. Digital mixes create hard-to-trace communications by using a chain of proxy servers. Each message is encrypted to each proxy using public key cryptography; the resulting encryption is layered like a Russian doll with the message as the...
and distributed datastoreDistributed file systemNetwork file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...
to provide anonymity (freeware, written for WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
) - StegoShareStegoShareStegoShare is a steganography tool, that allows to embed large files into multiple images. It may be used for anonymous file sharing.-Features:* Supports various image formats...
- a steganography software may be used for anonymous file sharing - StealthNetStealthNetStealthNet is a anonymous P2P file sharing software based on the original RShare client, and has been enhanced.- Drawbacks :* There is no technical documentation about the network protocol.* Anonymity is unproven....
- the successor to RShare - SyndieSyndieSyndie is an open source cross-platform computer application to syndicate data over a variety of anonymous and non-anonymous computer networks.-Features:...
- a content syndication program that operates over numerous anonymous and non-anonymous networks - VuzeVuzeVuze is a BitTorrent client used to transfer files via the BitTorrent protocol. Vuze is written in Java, and uses the Azureus Engine. In addition to downloading data linked to by .torrent files, Azureus allows users to view, publish and share original DVD and HD quality video content...
(formerly Azureus) - a BitTorrent clientBitTorrent clientBitTorrent is a peer-to-peer program developed by Bram Cohen and BitTorrent, Inc. used for uploading and downloading files via the BitTorrent protocol. BitTorrent was the first client written for the protocol. It is often nicknamed Mainline by developers denoting its official origins. Since version...
with the option of using I2PI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
or TorTor (anonymity network)Tor is a system intended to enable online anonymity. Tor client software routes Internet traffic through a worldwide volunteer network of servers in order to conceal a user's location or usage from someone conducting network surveillance or traffic analysis...
(open source, written in Java) - WinnyWinnyWinny is a Japanese peer-to-peer file-sharing program which claims to be loosely inspired by the design principles behind the Freenet network, which keep user identities untraceable...
- a P2P client that is very popular in Japan (freeware, written in C++ for Windows)
Defunct or dormant
- ANts P2PANts P2PANts P2P is an anonymous peer-to-peer open source file sharing software written in Java. The software was initially conceived in 2003 to explore the potentials offered by a number of novel routing protocols based on swarm intelligence...
- file sharing and HTTP publishing - BitblinderBitblinderBitblinder was an open source software program that allows users to share bandwidth and IP addresses in order to anonymously download torrents and browse the internet. It was first released in June 2009. It was developed by Josh Albrecht and Matthew Kaniaris of Innominet...
- EntropyEntropy (anonymous data store)Entropy was a decentralized, peer-to-peer communication network designed to be resistant to censorship, much like Freenet. Entropy was an anonymous data store written in the C programming language. It pooled the contributed bandwidth and storage space of member computers to allowed users to...
- I2Phex - a Gnutella client which communicates anonymously through I2PI2PI2P is a mixed-license, free and open source project building an anonymous network .The network is a simple layer that applications can use to anonymously and securely send...
- MarabuntaMarabuntaMarabunta is a fully distributed software application for anonymous P2P. The main goal is the fight against internet censorship and assuring the freedom of speech...
- for chatting only - MUTEMUTEThe MUTE Network is an unmaintained peer-to-peer file sharing network developed with anonymity in mind. The MUTE client is open source software released under the Public domain and includes support for the Linux, Mac OS X and Microsoft Windows computer operating systems.-History of MUTE:MUTE was...
- file sharing - Rodi - a file sharing client which allows for a low degree of anonymity
- RShareRShareRShare is an anonymising peer-to-peer file sharing system. It offers resistance to the analysis of who downloads or shares files, with strong encryption to resist traffic sniffing...
- file sharing
Private P2P clients
Private P2PPrivate P2P
Private peer-to-peer systems are peer-to-peer systems that allow only mutually trusted peers to participate. This can be achieved by using a central server such as a Direct Connect hub to authenticate clients. Alternatively, users can exchange passwords or cryptographic keys with friends to form...
networks are P2P networks that only allow some mutually trusted computers to share files. This can be achieved by using a central server or hub to authenticate clients, in which case the functionality is similar to a private FTP
File Transfer Protocol
File Transfer Protocol is a standard network protocol used to transfer files from one host to another host over a TCP-based network, such as the Internet. FTP is built on a client-server architecture and utilizes separate control and data connections between the client and server...
server, but with files transferred directly between the clients. Alternatively, users can exchange passwords or keys with their friends to form a decentralized network.
Friend-to-friend clients
Friend-to-friendFriend-to-friend
A friend-to-friend computer network is a type of peer-to-peer network in which users only make direct connections with people they know. Passwords or digital signatures can be used for authentication....
networks are P2P networks that allows users only to make direct connections with people they know. Passwords or digital signatures can be used for authentication. Examples include Retroshare
Retroshare
RetroShare is free software for encrypted, serverless email, Instant messaging, BBS and filesharing based on a friend-to-friend built on GPG. It is not a strictly a darknet since peers can optionally communicate certificates and IP addresses from and to their friends.- Authentication and...
and OneSwarm
OneSwarm
OneSwarm is a privacy-preserving P2P client developed at the University of Washington. Although backward compatible with traditional BitTorrent clients, OneSwarm also includes new features designed to protect user privacy when sharing data among friends through creating a distributed darknet,...
.
Hypothetical
The following networks only exist as design or are in development- CrowdsCrowdsCrowds is a proposed anonymity network that gives probable innocence in the face of a large number of attackers. Crowds was designed by Michael K. Reiter and Aviel D. Rubin and defends against internal attackers and a corrupt receiver, but provides no anonymity against a global attacker or a local...
- Reiter and Rubin's system for "blending into a crowd" has a known attack - Herbivore - a distributed anonymous DC-communication system, providing private file sharing and messaging, under development at the Cornell University.
- P2PRIVP2PRIVP2PRIV is a conceptual anonymous peer-to-peer overlay network introduced at Warsaw University of Technology. P2PRIV hides an initiator of communications by a parallelization of network nodes receiving or sending user data independently. This concept is contrary to other anonymity networks topologies...
- Peer-to-Peer diRect and anonymous dIstribution oVerlay - anonymity via virtual links parallelization - currently in development and has significant, unsolved problems in a real world environment - PhantomPhantom Anonymity ProtocolThe Phantom anonymity protocol was designed in 2008 by Swedish security researcher Magnus Bråding to provide anonymity optimized for the current conditions and needs of average internet users. The design goal was feasibility for mass adoption as a de facto internet anonymization standard...
- a fully decentralized high-throughput anonymization network currently working on a plan to implement it - AnoANOAno or ANO may refer to:* Ano, Ethiopia* Ano family, a noble family of Japan* Ano , a sport with two 12 cm balls, conducted at Tuvalu* Abu Nidal Organization, Palestinian Revolutionary Council, founded by Abu Nidal...
- extensible IP anonymizer with steganography support (in development)
Defunct or dormant
- Invisible IRC Project - anonymous IRCInternet Relay ChatInternet Relay Chat is a protocol for real-time Internet text messaging or synchronous conferencing. It is mainly designed for group communication in discussion forums, called channels, but also allows one-to-one communication via private message as well as chat and data transfer, including file...
- Mnet - a distributed file systemDistributed file systemNetwork file system may refer to:* A distributed file system, which is accessed over a computer network* Network File System , a specific brand of distributed file system...
- inactive now - BitblinderBitblinderBitblinder was an open source software program that allows users to share bandwidth and IP addresses in order to anonymously download torrents and browse the internet. It was first released in June 2009. It was developed by Josh Albrecht and Matthew Kaniaris of Innominet...
- a decentralised P2P anonymity software program which included Tor but with increased speed. Website is down and clients are no longer functional.
Anonymous P2P in a wireless mesh network
It is possible to implement anonymous P2P on a wireless mesh networkWireless mesh network
A wireless mesh network is a communications network made up of radio nodes organized in a mesh topology. Wireless mesh networks often consist of mesh clients, mesh routers and gateways.The mesh clients are often laptops, cell phones and other wireless devices while the mesh routers forward traffic...
; unlike fixed Internet connections, users don't need to sign up with an ISP to participate in such a network, and are only identifiable through their hardware. Even if a government were to outlaw the use of wireless P2P software, it would be difficult to enforce such a ban without a considerable infringement of personal freedoms. Alternatively, the government could outlaw the purchase of the wireless hardware itself. Protocols for wireless mesh networks are Optimized Link State Routing Protocol
Optimized link state routing protocol
The Optimized Link State Routing Protocol is an IP routing protocol optimized for mobile ad-hoc networks, which can also be used on other wireless ad-hoc networks. OLSR is a proactive link-state routing protocol, which uses hello and topology control messages to discover and then disseminate...
(OLSR) and the follow-up protocol B.A.T.M.A.N.
B.A.T.M.A.N.
The Better Approach To Mobile Adhoc Networking, or B.A.T.M.A.N., is a routing protocol which is currently under development by the “Freifunk”-Community and intended to replace OLSR....
, which is designed for decentralized auto-IP assignment. See also Netsukuku
Netsukuku
Netsukuku is the name of an experimental peer-to-peer routing system, developed by the in 2006, created to build up a distributed network, anonymous and censorship-free, fully independent but not necessarily separated from the Internet, without the support of any server, ISP and no central...
.
See also
- Anonymity applicationAnonymity applicationAn anonymity application is any software application which can be used to access a network, such as the Internet, anonymously. The application can use either private or public anonymous proxy servers, encryption or even spoofing, diversion and obfuscation to ensure an anonymous and/or difficultly...
- Comparison of file sharing applicationsComparison of file sharing applicationsFile sharing is a method of distributing electronically stored information such as computer programs and digital media. Below is a list of file sharing applications....
- Secure communicationSecure communicationWhen two entities are communicating and do not want a third party to listen in, they need to communicate in a way not susceptible to eavesdropping or interception. This is known as communicating in a secure manner or secure communication...
- Dining cryptographers protocol
External links
- Anomos - Anonymous BitTorrent
- AnoTorrent - Anonymous P2P BitTorrent
- Anonymous-p2p.org
- Planet Peer Board - discussion on anonymous P2P
- Planet Peer Wiki - a wikiWikiA wiki is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor. Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include...
about various anonymous P2P applications - A Survey of Anonymous Peer-to-Peer File-Sharing
- Models for Anonymous-p2p Dr. Fabio Dianda - CNR - Italy
- anoNet
- Cashmere : resilient anonymous routing