Q. How are people still tweeting in Turkey?
A. Users can change the “phone book” their computer uses. The domain name system has multiple copies of these phone books, all of which are supposed to be identical. The Internet access provider usually picks the one used, but users can change settings on their machines to a different one. That way, Twitter.com would pull up the real IP address for Twitter's website.
People also can use masking services called proxies. A person's PC or mobile device connects to the proxy, which uses its own domain name servers to reach out to Twitter on the user's behalf. Turkish access providers know only that the user is reaching the proxy, not Twitter. Instead of a proxy, people can also use virtual private networks, the tools common for accessing secured corporate networks from home. Just like proxies, VPNs reach out to websites on users' behalf. Plenty of free VPNs exist.
Twitter can also be accessed by text messaging. In fact, the reason tweets are limited to 140 characters is to fit the length constraints of texts. Twitter Inc. posted on its Policy account instructions on how to send tweets through texts. The guidelines are in both English and Turkish. It's possible to receive texts on followed accounts as well, though users must enable that one account at a time. Keep in mind that this is a Twitter feature that won't work with other sites that get blocked.
Users also might be able to turn to Twitter aggregation services such as HootSuite. It's similar to a proxy in that the aggregation service is what's making contact with Twitter. The user's computer looks up the IP address for that service, not Twitter. Many of these services let people both post and read tweets.
Q. What's the big deal about the ban if it can be circumvented?
A. These circumvention techniques aren't easy for everyone to carry out. Think of the last time you had to help a tech-challenged friend or relative do something relatively simple, such as attaching a photo to an email.
The government also might step up its blocking efforts, as China does every time a new hole pops up. If people are using HootSuite, the IP address for that website can be changed as well. Proxies and VPNs can be blocked, too. If changing the domain name servers proves ineffective, there are other ways to carry out a ban - including content filtering based on keywords.
Andrew Przybylski, a researcher at Oxford Internet Institute in Britain, said Turkey's techniques so far appear relatively primitive.
“This is Round One of something that could easily escalate,” Przybylski said. The domain name system is “the easiest to block, and then the easiest to get around the block. It's more the mindset here.”
