Connecting computers to networks significantly increases risk. Networks connect large numbers of users to share information and resources, but network security depends heavily on the cooperation of each user.
Security is as strong as the weakest link.
Studies have shown that most of the abuses and frauds are carried out by authorized users, not outsiders. As the number of LANs and WANs increase, cost-effective security becomes a much more significant issue to deter fraud, waste, and abuse and to avoid embarrassment. This chapter is intended to help LAN managers understand why they should be concerned about security, what their security concerns should be, and how to resolve their concerns. We will begin by introducing the concept of risk management and touch on basic requirements for protecting LANs. This will be followed by a summary of LAN components and features that will serve as a foundation for determining security requirements.