A Method To Evade Keyword Based Censorship

Abstract

Many countries block the content of web pages which are deemed against the morals, religious rules or policies set by government or organization. Countries like China block the post which is against their government interest. Germany blocks contents related to Neo-Nazi group. Most of these web pages are subjected to IP address blocking, DNS poisoning and keyword based filtering. We mainly focus on keyword based filtering as it is fine grained filtering technique where the contents of web pages are filtered using blacklisting. So with increase in surveillance over network, arms race for circumvention techniques has also increased. We propose an application framework that provides you an evading technique that allows users to read the blog pages on Internet. This framework allows posing content on sites by replacing the sensitive words in a page by images or uncommon unblocked dictionary words thus bypassing censors. There are three ways to present the blog page so as to bypass censors; Colored dictionary type, Plain dictionary type and Image type. We performed within group-experiments to confirm if the users were able to adopt to this new techniques. Users were asked to read web pages and answer few questions based on the content of blogs to analyze if they could read and understand the content. Users were also asked about their experience reading the page and rate it on difficulty scale of 1 to 5.We measured various metrics according to time complexity, correctness and user response. Time complexity included reading time and time taken by users to answer the questions. Results shows that their was varied response to each type but overall Colored dictionary type was more favored than Image and Plain dictionary.