OPUS: Six Strategies for Defense-in-Depth

Serious issues often originate inside the network: everything from worms, viruses, and Trojan horses to unsecured wireless networks, peer-to-peer mobile communications and guest users can compromise the security of corporate networks. Thus, to address these threats, the corporate network should no longer be a single homogeneous zone in which users connect from anywhere in the network and receive the same levels of access. Instead, the network requires internal perimeterization and defenses.