At this point, you may be thinking that EFS is just about as complex a system as you would ever want to deploy to users. But data communications security is just as important as data storage security, and that means you'll need to use several other Windows Server 2003 features that are even more intimidating. This includes IP Security (IPSec), Transport Layer Security (TLS), and support for applications such as email (S/MIME). All of these features require a solid Public Key Infrastructure (PKI) deployment. So let's take a deep breath and plunge ahead.