This document discusses the history and future of security as a service (SaaS). It outlines how security has evolved from protecting individual computers to protecting networks and now personal digital data. The document suggests that SaaS is not a new concept, but rather the explicit outsourcing of security infrastructure to the cloud. It notes potential benefits of SaaS including managed security, authentication management, and ongoing security tasks like patching and logging. However, it also lists trust and potential marketing issues as concerns for the SaaS model. Ultimately, the document argues that SaaS could work if implemented thoughtfully to address ongoing security threats to user data and authentication.