Masterclass: Network Design Issues

Masterclass: Network Design Issues

Introduction
Throughout the course we have examined the techniques for analyzing
a target network and assessing the machines hosted within. To better
interpret the network results gained through our analysis it is desirable
to understand some of the secure network design philosophies in use
today, particularly those relating to the integration of the Corporate
LAN to the Internet.
Clearly the major concerns over network security relate to the integrity,
reliability and availability of the services and data. We will therefore
address secure network designs from those perspectives.

Initially, many corporate networks that connected to public networks
(i.e. the Internet) relied completely upon their router security at either
end of the serial connection (Figure 14 routers 1 and 2) to protect
internal hosts. In many instances this security was negligible or nonexistent.