Tor (formerly named Onion Router) is free software that provides online anonymity.
The main implementation of Tor is written in the C programming language and consists of approximately 146,000 lines of source code.
During its operation, the Tor browser directs Internet traffic through a free, worldwide network of more than three thousand links to hide the user's location and prevent any network tracking or traffic analysis. Using Tor significantly complicates the tracking of Internet activity, including visits to specific sites, sent and received Internet messages and other forms of communication. Tor browser is designed to protect the privacy of users, maintain their freedom and ability to conduct a confidential business.
The source data, including the destination, when working through this browser, are encrypted several times and sent through a virtual channel, which includes consecutive and randomly selected links. Each link recognizes the “layer” of encryption, which is detected only in the next link. The final link takes the last layer of encryption and transfers the source data, without revealing it or even not knowing the sender, to the destination. This method reduces the likelihood of interception of the source data and completely hides routing. For this reason, when the best browsers are mentioned, Tor takes one of the first places among them.
However, it also has weaknesses. Like all existing networks to ensure anonymity, Tor cannot and does not try to defend itself against monitoring traffic at the edge of its network. This means that entry and exit from the network can be viewed. In addition, the Tor browser provides protection against traffic analysis, however, it cannot prevent traffic recognition.
Despite the above disadvantages, Tor and alternative JonDonym (JAP) systems are considered more robust than their VPN alternative. Studies conducted to analyze the amount of encrypted data stream that passes through a VPN, Tor, or JonDo system have shown that the last two services are much more difficult to analyze.
Despite this, the operators of some Internet sites have the ability to prevent connections from Tor sites, or offer limited functionality for users of this browser. If you touch other free browsers, then it’s obvious that such restrictions no longer exist. For example, it is usually not possible to change data on Wikipedia when using Tor or even using an IP address that uses the Tor output node (this is recognized due to the use of the TorBlock extension).
Despite the many illegal and harmful things that some users do when using this service, it has significant approval for legitimate purposes. According to international data, Tor browser fits into a broader strategy of protecting privacy and anonymity. In recent years, there has been an increase in the popularity of this service associated with doing business on the network and making financial transactions.