Citizen Lab is publishing a report today that reveals hidden keyword blacklists that are used to censor chats on three popular Chinese live streaming applications, YY, 9158, and Sina Show. Contrary to prior research and assumptions that Internet censorship in China operates under a uniform set of guidelines, we find uneven implementation of censorship on the live streaming apps we studied.
Live streaming applications have gained huge popularity in China in recent years, with millions of users flocking to them to share karaoke performances, game sessions, and glimpses of their everyday lives. Popular streams attract hundreds of thousands of users who can chat with the live streamers and purchase virtual items to give them. The live streamers can in turn trade those items for cash. These platforms have given rise to a new generation of Internet celebrities who amass audiences, virtual gifts, product endorsements, and even venture capital investment from their video streams. However, the growing popularity of these apps has been met with increased pressure from the Chinese government to ensure real name registration of live streaming performers and censorship of prohibited content.
To examine how censorship works on these applications, we reverse engineered them and found that censorship is done on the client-side, meaning all the rules to perform censorship are inside of the application running on your phone or computer. We were able to collect the keyword lists used to trigger censorship of chat messages. Tracking changes to the keyword lists over the past year gives an inside look into how these applications implement censorship
- Censorship is reactive often in response to current events.
- The keyword lists between companies are not identical suggesting that there is no centralized list provided to them by authorities.
- Censored keywords include references to collective action and government criticism serving as a counterpoint to recent studies.
- Censored keywords include names of competitors, which appears to be motivated by business interests rather than government pressures.
The report is being published alongside a timeline that visualizes events censored by these applications over the past year. This report is part of the Net Alert project, an effort to make research on information controls more accessible. This research continues our work on tracking censorship of popular apps in China, which has included analysis of Sina Weibo, WeChat and other chat apps, and Web browsers.