The following subsections present three situations that build on each other as the network and the needs of the enterprise change. Each type of authentication is demonstrated.
Consider the situation pictured in Figure 8.54. Assuming that all IPs used are routable (i.e., no NAT is necessary), let's implement the security policy listed below.
The Web server in the DMZ will be accessible via HTTP from anywhere.
The e-mail server in the DMZ will be accessible via SMTP from anywhere and via POP-3 from the internal networks.