OpenNet Initiative: Bulletin 007

Geolocation filtering: blocked during run-up to election

October 27, 2004
Last Updated: October 27, 2004

- Background
- Methodology & Results
- Conclusions
- About the OpenNet Initiative


The BBC, using data collected by Netcraft, reports that since Monday October 25th 2004, the official website of the Bush-Cheney campaign website ( has been restricted to Internet users located in the United States. Subsequent reports indicate that this filtering was implemented for unspecified security reasons.

Geolocation filtering refers to a situation when Internet content providers, such as websites, restrict or modify the content delivered to users based on geographical regions. This type of geographically-targeted filtering uses geolocation technology to determine an Internet user's geographic origin by looking up the requesting users' numerical Internet protocol (IP) address in databases that associate IP addresses with particular countries. Advanced geolocatation databases can also match regions and cities with specific IP addresses.

The primary difference between geolocation filtering and other forms of internet content filtering is that geolocation filtering is done by the target website, instead of an external third party (such as the user's Internet Service Provider, or along the national backbone between the user and the target website).

Examples of geolocation filtering include:

Methodology & Results

The ONI connected to remote computers located in fifty countries* around the world in order to test the accessibilty of We requested the website,, through these remote computers so that the geolocation filtering software would respond as if we were physically located in each of these countries. The testing was conducted on October 27, 2004, following the release of BBC's report. Out of the fifty locations tested, only those in Canada and the United States were able to access All others were shown an Access Denied page. However alternative URLs to reaching the content are still globally accessible, such as and

These results show a map of which countries were able to reach the website.


According to the non-governmental organization American Citizens Abroad, as of 1999 over one million United States citizens live in Mexico, over one million live in Europe and over four million live around the world. Under typical circumstances, none of these citizens are able to access to George W Bush's website during the run-up to the presidential election.

Wired reports that geolocation technology companies claim an accuracy rate of up to 99% when filtering by country and higher than 80% when filtering at the city level. During the Yahoo! France case, a panel of experts, including Vint Cerf, argued that there was no way for Yahoo! to restrict access to all Internet users in France but suggested that using overlapping mechanisms of geofiltering Yahoo! could block nearly 90% of them.

Geolocation technology is thus not always accurate, leading to situations in which there is both over and under blocking. Users or locations that are targeted for geolocation filtering may be mistakenly denied access to specific content they are supposed to be allowed to access. Conversely, users may have access to information that they were not intended to be allowed to access. There are also ways in which users can employ the use of proxy servers and anonymous communications sysems to disguise their true location from geolocation technologies.

Although generally used by specific, individual websites to restrict access or to deliver targeted content to users based on geographic location, geolocation technology allows for content to be modified subtly or restricted within specific target areas. When used in conjunction with self-censorship strategies, geolocation filtering adds an additional level of fine grain control over Internet filtering, and raises questions about the gradual stifling of the global commons of information that the world-wide web initially promised.

About the OpenNet Initiative

The OpenNet Initiative is a partnership of the Citizen Lab at the Munk Centre for International Studies, University of Toronto, the Berkman Center for Internet & Society at Harvard Law School, and the Advanced Network Research Group at the Cambridge Security Programme, University of Cambridge.

The OpenNet Initiative releases occasional bulletins based on our ongoing research. These bulletins are meant to be limited responses to current events, policy debates, and/or issues raised by our ongoing research that we feel justify immediate wider circulation. Our more detailed analyses can be found in our major reports.


* This list includes Hong Kong and Taiwan.,1377,64178,00.html