Internet sites ‘blocked by censors’ as China hosts world web conference

The action comes as China hosts the World Internet Conference, which brings together many of the world’s top technology companies.

EdgeCast, an affiliate of Verizon, said censors have taken down several networks that provide local servers to help speed up website performance.

EdgeCast provides such a network, and its clients include software company Mozilla, publishing company The Atlantic and content management system Drupal.

The online activist group Greatfire.org said it was the target of the Chinese action, which blocked many other sites that use EdgeCast. The group enables Chinese internet users to access websites otherwise blocked by Chinese censors.

A Greatfire.org co-founder, who goes by the pseudonym Charlie Smith, said they had chosen to use several content delivery networks knowing that any move to take down their site would affect others.

“We knew that ahead of time,” he said. “It was our feeling that the authorities would not take that kind of action.”

China employs thousands of censors who block hundreds of websites and erase social media messages dealing with sensitive political topics. At the same time, it claims some of the world’s most popular online sites, including e-commerce giant Alibaba.