Local Area Network Security 263 14. The Perimeter In Figure 10.3, you will see yet another IP network labeled demilitarized zone (DMZ). You may ask, why yet another network? The rationale behind this design is as follows. The users that belong to IN might want to access the resources on the Internet, such as read their email and send email to the users on the Internet. The corporation needs to advertise its products on the Internet. The DMZ is the perimeter network, where resources have public IP addresses, so they are seen and heard on the Internet. The resources such as the Web (HTTP), email (SMTP), and domain name server (DNS) are placed in the DMZ, whereas the rest of the resources that