National Internet Censorship Cascades When ISPs Share Infrastructure And Data

Canadian researchers have uncovered a case of national Internet censorship being passed on to users in another country thanks to shared Internet connections. The Citizen Lab at the Munk School of Global Affairs at the University of Toronto says in a July paper (.pdf) that it examined Internet traffic in Oman over a period of 10 days in June to look for evidence of what it calls "upstream filtering."

That's when censorship controls placed by one Internet service provider end up likewise censoring the Internet connections of another ISP due to data flowing through the infrastructure of the first ISP in order to reach customers of the second. Oman is no paradigm of an open Internet since the major Omani ISP, Omantel (owned by the sultanate), filters online pornography, circumvention tools and other content deemed objectionable such as websites critical of religion.