Chinese netizens have expressed concern that their government may only be months away from having the ability to cut them off from overseas websites altogether.
Rumors were rife on the popular chat service QQ this week that China's Ministry of Industry and Information Technology was stepping up plans to funnel all Web traffic between China and overseas sites through a single route.
In doing so, the government would have the option to "cut off" China's Internet from the outside world entirely.
Chinese technology analyst Li Li said that while the rumors were probably exaggerated, the government was more likely to be working on ways to limit overseas access to sites it hasn't approved in advance, however.
"I think these reports probably aren't correct," Li said. "What's more likely is that the government is compiling a 'whitelist' of sites."
Li said the government would also probably limit access to netizens using encrypted connections.
"It's very likely that they will find a way to cut off access via circumvention tools," he said.
A total 'kill switch'
Legal scholar He Weifang said there were few legal obstacles to a total "kill switch" for the Internet in China, however.
"The practice of pulling the plug on the Internet didn't start in Xinjiang; it started in Tibet," He said, referring to regional Internet shutdowns during unrest in July 2009 and March 2008 respectively.
"In a democratic country, you can't just take away people's rights like that, but [in China] they can take away whatever they like."
Internet services in the troubled northwestern region of Xinjiang were subject to a full and then partial lockdown since ethnic rioting was sparked in July 2009 by a Uyghur demonstration in the regional capital, Urumqi.
Even when general online access was restored more than 300 days later, popular Uyghur-language websites still remained offline, with some editors of Uyghur websites detained under national security charges.
New tools likely
Experts say the transition to IPv6 network addresses, from the current generation of IPv4 addresses used to identify computers and devices online, could give Beijing a far more powerful tool in the continuing development of its system of Internet blocks and filters known as the Great Firewall, or GFW.
Prominent blogger Beifeng said he did not believe Beijing is close to developing a "kill switch." But he said more sensitive filters and online user identification tools are very likely.
"This means that only people who really need to will be able to access the Internet [freely], like scholars who need it for their research," he said. "I think that's very likely."
"[The Communist Party's] highest aim is to stay in power."
New law
Chinese lawmakers have drafted a new state secrets law that will, if passed, require Internet service providers to release information about anyone who uses their networks to leak sensitive material.
China habitually uses state security and state secrecy charges to imprison people who air unpopular political views online, or who give information to journalists that would otherwise be censored by online filters, blocks, and top-down directives.
Egyptian authorities cut off all Internet access in late January amid a wave of anti-government protests in that country, sparking debate about how far government control of online activity should be allowed to reach.
In Washington, the Cybersecurity and Internet Freedom Bill, often referred to as the "Internet kill switch," currently being debated in Congress would give the White House authority to declare a "cyber emergency," enabling bureaucrats to issue mandates to Internet companies to protect cyber-security.
Reported by Xin Yu for RFA's Mandarin service. Translated and written in English by Luisetta Mudie.