Apply a few basic hardening principles to secure your cloud environment. I've written about simple server-hardening techniques in the past. Those articles were inspired in part by the Linux Hardening in Hostile Networks book I was writing at the time, and the idea was to distill the many different hardening steps you might want to perform on a server into a few simple steps that everyone should do. In this article, I take the same approach only with a specific focus on hardening cloud infrastructure. I'm most familiar with AWS, so my hardening steps are geared toward that platform and use AWS terminology (such as Security Groups and VPC), but as I'm not a fan of vendor lock-in, I try to include steps that are general enough that you should be able to adapt them to other providers.