However, once the first bank became a victim, immediately all the other institutions started to learn more about the attacks, search for solutions, then deploy those solutions quickly. When I look at military cloud security solutions, there are many vendors and partners providing tools and solutions, but not many providing availability security embedded computer attacks are hurting the availability of online services and many antivirus vendors and firewall vendors do not focus on the availability aspect.”  Cloud providers find protecting the shared infrastructure can be challenging because it is an expensive up-front cost, he continues. 

refer to : http://mil-embedded.com/articles/cloud-security-the-dod/