Anonymity-Enabled Communication Channels: Attacks and Defense Methods

Within information security, anonymous communication has gained momentum and helps to achieve a quantum leap in privacy due to its unique properties like anonymity, un-traceability, un-observability, and pseudonymity. Although end-to-end encryption guarantees the security of the data, it is not able to secure the metadata within the communication channel thereby putting the privacy of the users to be vulnerable. An overview of anonymous communication channels has been delineated in this research work, starting from Chaum’s mix network, DC-nets, onion routing, and other anonymous routing protocols. Although anonymous communication channels are becoming a hot topic to preserve security, the attacks on these channels are endless. To break down this anonymity, eavesdropper uses different types of attacking methods from time to time. This research provides the overall survey of the attacks on anonymous communication channels. These different types of attacks have been analyzed. To overcome these attacks, various measures have been provided over time. We have analyzed these attacks along with their different defense countermeasures. The classical description of the attacks together with their defense methods are given.