Anonymous Communication

Abstract

Anonymous communication is thus a necessary measure to protect the privacy of users, and protect computer systems against traffic analysis. Anonymity systems seeks to build an infrastructure running on top of the existing Internet protocols that allows people to communicate with each other without necessarily revealing their personal network identifiers. The basic idea behind any anonymous system is to provide unlink ability between communicating parties by relaying traffic through a number of intermediate nodes. If the messages are delayed and buffered at these intermediate nodes then they can provide stronger anonymity. Such message based systems are suitable for high latency anonymous applications such as anonymous email. Such systems are called Mix based system. Circuit based randomized routing techniques like Onion Routing and TOR are used for providing low latency applications like anonymous web browsing or remote login. All these anonymous systems are used by are used by diverse group of users to protect their identities on the Internet.

Onion Routing

It is the most prevalent design for low-latency anonymous communication which is initially developed by Goldschlag.

Cypherpunk Remailers

These referred to as Type I remailers, were first developed by Hughes and Finney and are loosely based on Chaum’s mix design .The system consists of multiple, distributed servers. Clients pick a sequence of servers and include a header for each hop that specifies the next server in the path to which the payload should be forwarded.

Relay cells

Once a circuit has been established, the initiator can relay cells through it. Upon receiving a relay cell, an OR looks up the corresponding circuit, and decrypts the relay header and payload with the session key for that circuit. If the cell is headed away from the client OP the OR then checks whether the decrypted cell has a valid digest.

Incentives

Any successful anonymity network requires a diverse user base, as well as server operators all over the world. This requires to encourage people to participate in an anonymity system by providing incentives. For example the Freedom Network took a commercial approach, by paying people to operate servers and charging clients a subscription fee for the service.

Scalability

As the general public becomes increasingly concerned about threats to personal privacy on the Internet, the number of users of anonymity systems is likely to grow. For an anonymous communication system to be able to support truly ubiquitous use, designs must be able to support not just more users, but also more servers in the anonymity network.

Applications Of Anonymous Systems

Anonymity serves different interest for different user groups.

Vulnerabilities

Onion Routing is not invulnerable to traffic analysis attacks. With enough data, it is still possible to analyze usage patterns and make educated guesses about the routing of messages. Also, since our application requires real time communication, it may be possible to detect the near simultaneous opening ofconnections on the firrst and last proxy servers revealing who is requesting what information.

 Conclusion

 Researches in the last 30 years have made significant progress towards enabling private and anonymous communication on the Internet. With an increasing level of public awareness about threats to personal privacy, such as identity theft or online advertisers tracking user behavior, academic and public interest in anonymous communication systems is likely to continue to increase in the near future.