Real-time monitor tracks the growing use of network filters for censorship

By | March 3, 2020
map of the world showing censorship activity
(The Michigan Engineer)

Researchers at U-M have discovered the widespread use of popular, commercial network filtering technologies for purposes of censorship in as many as 103 countries around the world. With a framework they call FilterMap, the researchers took advantage of several tools designed to detect censorship in real time to call attention to the proliferation of this technology for these unintended purposes.

The team says their framework can scalably and semi-automatically monitor the use of filtering technologies for censorship at global scale. They identified the use of 90 such filters, and are now able to continuously monitor their use.

Typically these types of network filters, including products from such well-known commercial manufacturers as Palo Alto Networks and Cisco, enable particular workplace or academic networks to restrict access to content determined to be unsafe or inappropriate. Their application for purposes of general internet censorship qualifies the systems as a type of “dual-use technology.”