Internet censorship is broadly defined as blocking access to websites, Internet outages and shutdowns, online trolling and self-censorship online. Netalitica focuses on investigating Internet blocking occurring on the network level such as blocking of websites and applications by local Internet Service Providers (ISPs).

In authoritarian states, ISPs fulfill “requests” from authorities to block access to specific content for political, economic, religious and other reasons. Democratic and authoritarian countries alike may adopt restrictive Internet legislations that oblige local ISPs to block access to certain content (e.g. child pornography, hate speech, terrorist and militant websites) in order to protect society. Such legislations may be vaguely formulated, thus leaving room for blocking liberal voices as well.

OpenNet Initiative, ONI Access and Freedom House provide great overview of the censorship regimes in countries around the world. Other useful sources include Citizen Lab , Reporters Without Borders, Article 19, Internet Monitor.

ISPs can block access to select websites by a variety of methods such as IP blocking, DNS tempering, HTTP blocking, SNI filtering. The Open Observatory for Network Interference (OONI) provides an overview of these techniques. Their open-source app OONI Probe represents the industry standard for measuring Internet censorship. It uses Citizen Lab test lists to uncover blocking of websites in more than 200 countries. Other popular network measurement projects include Censored Planet and ICLab.

Citizen Lab test lists are available for download on GitHub. Each country list is made of popular locally websites that are organized into 30 thematic categories encompassing all spheres of social life (e.g. environment, communication tools, economics, political criticism, human rights, news media, and others). Besides individual country lists, there is also the Global test list, which is made of websites that have universal usability (e.g. Facebook, YouTube, Twitter, CNN, BBC, DW).

Staring in 2019, Netalitica has hired researchers to update the Citizen Lab test lists for 50 countries from Asia, Africa, MENA, CIS, Latin America and Europe. Our researchers clean existing lists from faulty URLs, add fresh websites and balance the lists to make sure all thematic categories are populated with websites.