The U.S. Department of Homeland Security has been working with U.S. banks, energy firms and other private companies to test possible solutions to cyber attacks and learn more about how attackers view external systems and infrastructure. According to Krebs on Security, the efforts “are part of a little-known program at DHS designed to help ‘critical infrastructure’ companies shore up their computer and network defenses against real-world adversaries. And it’s all free of charge.” National Cybersecurity Assessments and Technical Services (NCATS) provides testing through two programs — a “Risk and Vulnerability Assessment” and “Cyber Hygiene” evaluation.