"The Net interprets censorship as damage, and routes around it" - John Gilmore, Electronic Frontier Foundation

The Beijing trial of businessman Lin Hai, accused of distributing 30,000 e-mail addresses to a pro-democracy journal, emphasises China's position at the epicentre of a conflict over the free flow of information on the Internet.

A totalitarian state trying to impose order and control on the anarchic Net always promised to be a battle royal, and it is being waged on several fronts:

• Websites: China channels Internet access for its one million users, who have to register with the police, through government-controlled servers in Beijing, Shanghai and Shenzhen. This means it can block access to sites it considers subversive.

  But last weekend hackers breached the servers' firewalls, a form of Internet security, according to a Wired News report. They instructed the software to ignore the list of banned addresses, which the hackers said included ones at the BBC, ABC, MSNBC and Wired.

• E-mail: The authorities may deter dissidents from using e-mail to further their cause by finding Lin Hai guilty and imposing a stiff sentence. But in practice, e-mail can be anonymous, encrypted and hard to intercept. The hacker group Cult of the Dead Cow is developing an e-mail plug-in which will allow Chinese users to receive e-mails of banned Web pages.

• Newsgroups:China has blocked access to newsgroups. Users could get round this with an international call to an Internet Service Provider outside China.

• Official sites:The Chinese government is exploiting the Internet as a propaganda tool. In October, it launched a site defending its human rights record. But it was instantly hacked and replaced with a page denouncing it as propaganda and providing a link to Amnesty International.