中国的网络审查

We can also now trace complicit Bing Chinese censorship back to 2009 as highlighted by Nicholas Kristof. It looks like Microsoft has indeed changed its censorship mechanism after our research made headlines this week. But Bing is still seriously flawed on two fronts: its algorithm favors pro-Chinese government websites by default on all search terms in simplified Chinese and their front end mistakenly delivers explicit censorship of search results on some search terms for users from all over the world.

Microsoft says: “The results themselves are and were unaltered outside of China”. This is simply not true.

在国际调查记者同盟发布“机密文件披露中国精英的海外资产”后，中国大量封锁外媒网站。 以下网站都是因为转发此新闻被封锁。以往中国很少封锁外语网站。

网站	主语言	文章
http://www.icij.org	英文	中文
http://www.theguardian.com	英文	英文

Yesterday we witnessed one of the largest Internet outages ever in China. We have three theories about why this outage may have occurred - two related to the Falun Gong but our third theory is that the Chinese authorities set out to attack our unblockable mirror websites.

From 15:30 to 16:30 (China time) on January 21, DNS lookup to any domain would incorrectly resolve to 65.49.2.178. Websites inside and outside of China were affected. Even Baidu and Sina were inaccessible. Only software using IP directly (e.g. QQ, VPNs) worked during that time. Attempts to visit any website redirected to http://65.49.2.178, which didn’t respond during that time.  The overwhelming traffic to this IP likely crashed the server.

Timeline	Event
15:15	GFW DNS poisoning begins. First recorded instance.
15:17	Local DNS servers began to cache incorrect responses. Some large websites in China began to be affected e.g Sina Weibo.
	Incorrect DNS continue to spread through Chinese DNS servers. Major websites including Baidu, Sina affected.
15:39	DNS poisoning lifted by GFW. But local DNS resolvers cached incorrect responses. Users continued to experience outage.
16:00