A Proxy Identifier Based on Patterns in Traffic Flows

Proxies are used commonly on today´s Internet. On one hand, end users can choose to use proxies for hiding their identities for privacy reasons. On the other hand, ubiquitous systems can use it for intercepting the traffic for purposes such as caching. In addition, attackers can use such technologies to anonymize their malicious behaviours and hide their identities. Identification of such behaviours is important for defense applications since it can facilitate the assessment of security threats. The objective of this paper is to identify proxy traffic as seen in a traffic log file without any access to the proxy server or the clients behind it. To achieve this: (i) we employ a mixture of log files to represent real-life proxy behavior, and (ii) we design and develop a data driven machine learning based approach to provide recommendations for the automatic identification of such behaviours. Our results show that we are able to achieve our objective with a promising performance even though the problem is very challenging.