DNS blocking in Latin America: a comparative study across political systems

Abstract

This report documents DNS practices across six countries in Latin America: Argentina, Cuba, El Salvador, Honduras, Uruguay, and Venezuela. Researchers tested 4,635 websites using local and VPN-based measurements as well as conducted desk research and expert interviews, as part of a hands-on collaborative teaching and research project on internet censorship. The study found that there are no significant differences in how the DNS is technically blocked in repressive and democratic contexts and that the scale of blocking in these countries varies dramatically. In democracies with transparent legal processes such as Argentina and Uruguay, gambling sites and other copyright issues dominate the blocking instances, and this technical practice matches the publication of the legal orders for commercial enforcement. In authoritarian countries, this research showed far smaller amounts of DNS blocking, while the qualitative evidence reveals extensive political censorship and the cultivation of cultures of self-censorship and self-regulation of speech. Additionally, this research finds that commercial VPNs are effective in bypassing a large majority (86-97%) of these blocks. While testing DNS blocking remains a relevant approach to study Internet censorship practices, to comprehensively analyze internet censorship in a country or region, there is a need to integrate other complementary technical and non-technical methodologies.