A Survey of Internet Censorship and its Measurement: Methodology, Trends, and Challenges

Internet censorship limits the access of nodes residing within a specific network environment to the public Internet, and vice versa. During the last decade, techniques for conducting Internet censorship have been developed further. Consequently, methodology for measuring Internet censorship had been improved as well. In this paper, we firstly provide a survey of Internet censorship techniques. Secondly, we survey censorship measurement methodology, including a coverage of available datasets. In cases where it is beneficial, we bridge the terminology and taxonomy of Internet censorship with related domains, namely traffic obfuscation and information hiding. We cover both, technical and human aspects, as well as recent trends, and challenges.