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Global Cyber Alliance
Global Cyber Alliance

Global Cyber Alliance

About the Global Cyber Alliance

The Global Cyber Alliance (GCA) is an international, cross-sector effort dedicated to confronting cyber risk and improving our connected world. It is a catalyst to bring communities of interest and affiliations together in an environment that sparks innovation with concrete, measurable achievements. While most efforts at addressing cyber risk have been industry, sector, or geographically specific, GCA partners across borders and sectors. GCA’s mantra “Do Something. Measure It.” is a direct reflection of its mission to eradicate systemic cyber risks.

GCA, a 501(c)3, was founded in September 2015 by the Manhattan District Attorney’s Office, the City of London Police and the Center for Internet Security. Learn more at .

GCA currently has two solutions for which we have developed tools and resources to improve the security of our cyber ecosystem.


GCA has made DMARC implementation simple with a free, easy-to-use online setup guide and a DMARC resource kit to aid with implementation and promote adoption.


Quad9 is a free, recursive, anycast DNS platform that provides end users robust security protections, high-performance, and privacy. Quad9, in collaboration with

GCA, IBM, and Packet Clearing House, routes your DNS queries through a secure network of servers around the globe. The system uses threat intelligence from multiple leading cyber security companies to give a real-time perspective on what Websites are safe and what sites are known to include malware or other threats. If the system detects that the site you want to reach is known to be infected, you'll automatically be blocked from entry - keeping your data and computer safe.

If you are interested in Quad9 protection, please visit the Website at ​​​​