China makes headlines every other week for its censorship of the Internet, but few people outside the country know what it's like to live with those access controls, or how to get around them.\nForeigners who visit the country should expect some headaches. Be prepared to live without Google, Twitter and your favorite daily newspapers, and to have a hard time connecting with friends back home, or even firing off an email. That's how bad it can get.\n+ Also on Network World: +\n"Connection Timed Out" is the dreaded error message when you try to visit a blocked site. It makes you think the site itself is down, but it's actually the "Great Firewall" at work, a vast censorship system that blocks access to many of the world's most popular services.\nI've lived in China for close to six years and censorship has been a near constant, lurking in the background ready to "harmonize" the Web and throw a wrench in my online viewing.\nIt's been especially evident this month. Google's services, which don't follow the strict censorship rules, are currently blocked. How long that will last is unknown, but it coincides with the 25th anniversary of the Tiananmen Square protests earlier this month -- an event the Chinese government wants no one to remember.\nLosing access to the world's biggest search engine is enough of a nuisance, but the censorship also affects Gmail, Google Talk, Google Calendar, Google Play, the Chrome browser, and even the news and weather widget that loads on my Android phone. Some of those services are running erratically or not at all. Most annoying is that friends can send me messages on Google Hangouts but for some reason I can't reply.\nThe censorship is a culture shock for foreigners visiting China for the first time. They expect to chat with friends on Facebook or Twitter only to find those services unavailable. Major publications like The New York Times, The Wall Street Journal and Bloomberg are blocked. You need to find alternatives for all these things. I often end up using Microsoft Bing, which complies with China's censorship rules.\nPlenty of other foreign websites are accessible, including Reddit, Buzzfeed, Yahoo, and politically non-sensitive Wikipedia pages. Most foreigners here end up subscribing to Virtual Private Networks (VPNs), which let you mask your location and bypass the censorship. I've been using a VPN for four years and the US$7 a month is money well spent for access to the entire Internet.\nChina's censorship wasn't always this strict. When I arrived to teach English here in late 2008, Facebook, Twitter and YouTube all were available and I could use Google's Blogger.com to record day-to-day experiences. All that ended in 2009 when China began blocking sites more actively. In March that year, supporters of the Dalai Lama -- an unwelcome figure here -- released a YouTube video that appears to show Chinese police beating Tibetans. A few months later, ethnic riots broke out in Western China, and the authorities cut access to Twitter and Facebook.\nBlogger.com had already fallen victim in May, and to keep my blog alive I emailed posts to my dad in the U.S. so he could update it for me. Eventually I bought a domain name and blogged through GoDaddy, which wasn't blocked.\nAll this censorship happens without official explanation. The Chinese government rarely mentions the topic or says why particular sites are blocked, but it's clear the authorities do everything they can to control what China's 618 million online users can access.\nAll local Chinese sites abide by the censorship rules or risk being shut down. That means China's largest search engine, Baidu, filters out sensitive content, like any mention of the Tiananmen Square protests. And social networks like Sina Weibo delete posts about contentious topics, or ban users who have gone too far. In rare cases, Chinese police have even sought out and arrested Internet users for starting online rumors.\nBut China's Internet is far from bland. While you can't access YouTube, Twitter or Google, there are Chinese equivalents, albeit with regulated content. Video sites show U.S. TV shows like "The Walking Dead" and "Homeland," and online users can discuss some controversial matters, like celebrity scandals and even corruption by low-level officials. But it all happens under the watchful eye of censors, who keep the discussions from crossing a line.\nIt's partly why many Chinese don't notice the censorship; there's enough leeway that the Internet is still a useful medium. Most don't miss Facebook or Twitter because they can connect via WeChat, a local messaging app used by hundreds of millions. China effectively has its own Internet, with its own providers and its own rules. So far, none of the big U.S. Internet firms has managed to make significant headway here, and the ones who try must play by the rules. LinkedIn, for instance, which entered the market this year, is drawing flak for blocking posts about political matters in China.\nThere's little sign that the country's stance on censorship will change anytime soon. The clampdowns on foreign services tend to come and go, but this latest block on Google could remain indefinitely. Last November, citing threats to stability, the government laid out plans to control access even more.\nI recommend anyone visiting China buys a subscription to a VPN service. I've used one provided by Astrill.com and it's a must-have for me. Hopefully China won't block it.