Twitter is slowly turning on automatic encryption on its website, a move following other major providers of web-based services to thwart account hijacking over wireless networks.
Twitter has offered an option for users to turn on SSL (Secure Sockets Layer) encryption, but said on Tuesday that it will turn the feature on by default for some users. It did not indicate when the option would be turned on by default for all users.
SSL encryption, indicted by "https" in the URL bar and sometimes a padlock in the browser window, is an encryption protocol used to protect communication between a client and a server. It is important to use because unencrypted information passed over wireless networks can be intercepted.
Many websites encrypt a person's login and password but will stop encrypting further data that is transmitted. A reason for not using SSL throughout a session is that it can occasionally slow interaction between the user and website.
Last year, a freelance web application developer named Eric Butler released Firesheep, an add-on for Firefox that snatches cookies transmitted on unencrypted networks. Web sites drop a cookie, or a small data file, into a person's web browser while they are logged into a session. Cookies are also used to "remember" people and keep them logged into the website.
Firesheep used an technique that was well-known but made it very easy for novice hackers to grab cookies and immediately log into a website as another person with just two clicks, known as session hijacking. If Firesheep detected someone logging into say, Facebook, on an open wireless network it would display their photo and name, which could be clicked in Firesheep, hijacking the person's account.
SSL would thwart such an attack since the cookie would encrypted. Other websites have started to step up their security as well. Facebook allows people to turn on SSL for a person's entire session in the "Account Settings" under "Security." In January 2010, Google turned on SSL for everyone using Gmail by default.