Project Shield is a so-called reverse proxy service that protects sites from being taken down by attackers who want to overwhelm their servers with data requests. In effect, sites using Project Shield can serve their sites to the public through Google’s infrastructure, which will then take the brunt of the attack when it comes.

These “distributed denial of service” (DDoS) attacks are a real problem for media – notable victims include the BBC and Gawker, but also many news sites in places like Nigeria, particularly around election time.

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“A simple, inexpensive distributed denial of service attack can be carried out by almost anyone with access to a computer — and take a site completely offline before its owners even know they’ve been attacked,” said Jared Cohen, the president of Jigsaw, a unit of Google parent Alphabet. “These attacks threaten free expression and access to information — two of Google’s core values.”

Jigsaw was until recently known as Google Ideas, and was rebranded this month to become Alphabet’s new think tank for tackling “geopolitical challenges.” Cohen, who used to work for U.S. State Department, has been an important bridge between Google and the government for many years.

“Project Shield is not just about protecting journalism. It’s about improving the health of the Internet by mitigating against a significant threat for publishers and people who want to publish content that some might find inconvenient. A free and open Internet depends on protecting the free flow of information — starting with the news,” Cohen wrote.

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Google/Alphabet/Jigsaw’s project is not unique. CloudFlare, probably the most prominent DDoS-protection outfit out there, has for a couple of years been offering a similar free service called Project Galileo, for the benefit of journalists, as well as political and artistic websites.

Project Galileo comes with the backing of the NGOs such as the American Civil Liberties Union, the Electronic Frontier Foundation (EFF) and the Reporters Without Borders. However, it’s a reactive service, meant for sites that have already come under attack — Project Shield appears more preventative in nature.

CloudFlare is also posing problems for users of the Tor anonymity tool (which is, after all, largely intended to protect free expression). The Tor folks have recently been on the warpath over the fact that sites protected by CloudFlare are near-inaccessible to Tor users, because CloudFlare’s system apparently can’t distinguish them from potential DDoS attackers.