1
Measuring Global Internet Filtering
Robert Faris and Nart Villeneuve
The Scope and Depth of Global Internet Filtering
In this chapter, we set out to provide an overview of the data regarding Internet filtering that
the OpenNet Initiative
1 has gathered over the past year. Empirical testing for Internet blocking
was carried out in forty countries in 2006. Of these forty countries, we found evidence of technical filtering in twenty-six (see table 1.1). This does not imply that only these countries filter
the Internet. The testing we carried out in 2006 constitutes the first step toward a comprehensive global assessment. Not only do we expect to find more countries that filter the Internet as
we expand our testing, but we also expect that some of the countries that did not show signs
of filtering in 2006 will institute filtering in subsequent years.
2
Conceptually, the methodology we employ is simple. We start by compiling lists of Web
sites that cover a wide range of topics targeted by Internet filtering. The topics are organized
into a taxonomy of categories that have been subject to blocking, ranging from gambling, pornography, and crude humor to political satire and Web sites that document human rights
abuses and corruption. (See table 1.2.) Researchers then test these lists to see which Web
sites are available from different locations within each country.
3
The states that filter the Internet must choose which topics to block (the scope of filtering)
and how much of each topic to filter (the depth of filtering). The results of these decisions are
summarized in figure 1.1, comparing the breadth and depth of filtering for the countries where
evidence of filtering was found.
The number of different categories in which Internet filtering was found to occur is shown on
the horizontal axis. We put this forward as a measure of the scope of Internet filtering in each
country. (The categories are shown in table 1.2.)
The vertical axis depicts the comprehensiveness of filtering efforts as measured by the highest degree of content blocked in any of the topical categories. This captures a markedly different angle on filtering. If the breadth of filtering represents the ambition of censors to limit
information related to a range of topics, the depth of filtering measures the success in actually
blocking content. This might correspond to the level of sophistication of the filtering regime
Measuring Global Internet Filtering
Robert Faris and Nart Villeneuve
The Scope and Depth of Global Internet Filtering
In this chapter, we set out to provide an overview of the data regarding Internet filtering that
the OpenNet Initiative
1 has gathered over the past year. Empirical testing for Internet blocking
was carried out in forty countries in 2006. Of these forty countries, we found evidence of technical filtering in twenty-six (see table 1.1). This does not imply that only these countries filter
the Internet. The testing we carried out in 2006 constitutes the first step toward a comprehensive global assessment. Not only do we expect to find more countries that filter the Internet as
we expand our testing, but we also expect that some of the countries that did not show signs
of filtering in 2006 will institute filtering in subsequent years.
2
Conceptually, the methodology we employ is simple. We start by compiling lists of Web
sites that cover a wide range of topics targeted by Internet filtering. The topics are organized
into a taxonomy of categories that have been subject to blocking, ranging from gambling, pornography, and crude humor to political satire and Web sites that document human rights
abuses and corruption. (See table 1.2.) Researchers then test these lists to see which Web
sites are available from different locations within each country.
3
The states that filter the Internet must choose which topics to block (the scope of filtering)
and how much of each topic to filter (the depth of filtering). The results of these decisions are
summarized in figure 1.1, comparing the breadth and depth of filtering for the countries where
evidence of filtering was found.
The number of different categories in which Internet filtering was found to occur is shown on
the horizontal axis. We put this forward as a measure of the scope of Internet filtering in each
country. (The categories are shown in table 1.2.)
The vertical axis depicts the comprehensiveness of filtering efforts as measured by the highest degree of content blocked in any of the topical categories. This captures a markedly different angle on filtering. If the breadth of filtering represents the ambition of censors to limit
information related to a range of topics, the depth of filtering measures the success in actually
blocking content. This might correspond to the level of sophistication of the filtering regime