Two things struck me when I first flew into Beijing: lack of sunlight and lack of Internet.

The sun, on many days, hangs behind a haze of pollution, its light filtered down to a soupy dusk. The Internet is stuck behind a government firewall, its main offerings obstructed to those living in China.

That neither the sun nor the Web is fully gone, merely crippled, makes dealing with their abbreviated selves especially annoying. You know their full versions are out there somewhere because they tease you most days. The sun’s orange halo might appear briefly at dawn, only to be engulfed by the smog. Gmail’s homepage might begin to load tentatively, only to stumble and freeze.

In many parts of the world (with some notable exceptions), we have come to count breathable air and unfettered Internet access among basic human conveniences, alongside indoor plumbing and access to education. That’s why it is so jarring and disorienting to suddenly lose them in Beijing to man-made forces of breakneck industrialization and censorship. No amount of reading or hearing about Beijing’s air pollution and the Great Firewall, as the system of Internet censorship is inevitably known, is enough to prepare you to deal with them.

For the moment, I’ll leave the sun where I hope it still is, wrapped away in a blanket of smog so thick I can barely see the high-rises less than a mile away. It smells faintly as if someone is burning tires.

Registration Required

The Great Firewall is a more complex and nuanced phenomenon, and it appears to be getting more capable in tripping up undesirable Web connections.

Like many foreigners in China, I signed up for a virtual private network, or VPN, geek-speak for a link to an overseas server, which allows you to leapfrog the Chinese Internet and plug straight into the real thing, as if you were sitting in New York or London. Twitter, the New York Times and Gmail loaded seamlessly on my iPad, ending a tense couple of days of withdrawal symptoms. And then it all crashed.

My VPN provider, a major player in the market, explained in an e-mail that the disruption was due to a recent update of the Great Firewall, referred to as the GFW, which “now has the ability to learn, discover and block VPN protocols automatically.”

The next day, the Global Times, a Chinese newspaper, ran an article headlined, “Foreign-run VPNs illegal in China: govt.” In it, the man known as the founding father of the Great Firewall was quoted as saying that foreign VPN providers needed to register with the government. “I haven’t heard that any foreign companies have registered,” Fang Binxing, who is now president of Beijing University of Posts and Telecommunications, told the newspaper.

Fang gained notoriety in 2011 when a student threw a shoe at him while he was delivering a lecture on cybersecurity. The shoe connected with the target. The student fled the scene and went into hiding, becoming an instant celebrity among the country’s many opponents of Internet curbs. Sometime later, hackers broke into the homepage of Binxing’s university and defaced it with an image from something called Angry Shoes, a spoof on the wildly popular “Angry Birds” game. The birds at the slingshot are replaced with shoes, and the pigs in the wooden house are replaced with Binxing’s face.

The most recent VPN disruption seemed intended to target mobile devices, which are fast becoming an important way to access the Internet. As my VPN provider promised to find a way to outwit the Great Firewall, several articles in state-run media reminded readers of the dangers lurking on the Web.

China’s Rationale

On Dec. 18, for instance, a commentary piece on Xinhua, China’s official news agency, called for new laws to govern the Internet: “If there is no strict legal punishments on the violators in cyber space, the negative factors will run wild to destroy the Internet order and even incite online violence, which will bring great damage to people and society.” This is the Chinese government’s original rationale for erecting the Great Firewall, an elaborate network of blocks, network slowdowns and censorship rules that keep many of China’s half- billion Internet users in the dark about events in the world and in their own country.

The unease about the broader issue of curbs on free speech was stoked anew recently when Mo Yan, the Chinese writer who won this year’s Nobel Prize for literature, seemed to liken censorship to airport-security checks: an indispensable nuisance.

China’s Internet is a strange place. Twitter and Facebook are blocked, their ability to disseminate unwelcome news and serve as organizing platforms for all sorts of protests deemed too grave a threat. Some of Google Inc.’s services, including Gmail, are intentionally slowed down to a snail’s pace, which is arguably even worse than being blocked outright because it gives customers an impression of poor service.

At the same time, Chinese clones of these American companies operate freely and load lightning-fast, their searches carefully scrubbed for sensitive terms by in-house censors. Western Internet companies that choose to enter the booming Chinese market have to play by the government’s rules.

The most striking example is Skype Inc., owned by Microsoft Corp. As detailed by, a website tracking all things related to the Great Firewall (and, of course, blocked by it), when you download Skype software in China, you are actually getting a product tweaked in a crucial way. Chinese Skype, a joint venture majority-owned by a local company, allows the government to monitor your chats.

Among the many curious things about the Chinese Internet, one apparent contradiction stands out. Xinhua, which insists on blocking Twitter, recently opened a Twitter account, sending out more than 3,000 tweets, and attracting 8,000 followers — following no one itself. Xinhua’s appearance on Twitter, and the one-way nature of its boosterish account, invited an avalanche of ridicule in the Chinese blogosphere.

Blocked Sites

Western news outlets that touch taboo subjects are blocked, too. and are both blocked because of their recent investigative reports on the financial dealings of top Chinese leaders.

How effective is the Great Firewall, given the many ways of leaping over it? China’s Internet sleuths aren’t overly concerned with how foreign companies and individuals access the Web, or what they read there. They are concerned about Chinese public opinion, and about ways to influence it by regulating what the Chinese people are and aren’t allowed to see on the Internet.

By that second measure, the firewall achieves its objectives just fine, despite the availability of VPNs and other technical tricks, many of them free.

Of China’s 500 million Web users, only about 1 percent “use these tools to get around censorship, either because most do not know how or because they lack sufficient interest in — or awareness of — what exists on the other side of the ‘great firewall,’” Rebecca MacKinnon writes in “Consent of the Networked,” a book on Internet freedom around the world.

Meanwhile, the wizards at my VPN provider finally found a way around the firewall’s latest crackdown on smartphones and tablets. My iPad is useful again, until the firewall catches on and a new round of cat-and-mouse begins.

Sadly, there’s no good news to report on breaching the wall of smog blocking the sun. No one has yet invented a virtual private network to transport one through the Beijing pollution.

Editor’s note: Philip Shishkin is a fellow at the Asia Society and the author of “Restless Valley: Revolution, Murder and Intrigue in the Heart of Central Asia,” to be published in May by Yale University Press. The opinions expressed are his own.