We use computer networks for everything from banking and investing online to communicating with others through email or chat programs. Due to the value of information on these networks, it has become a lucrative target for unauthorized users or criminals. To protect both the network and the information on it, network managers must consider taking some security measures. Security measures help you to stop unauthorized users from accessing any part of your computer network. As more and more people become 'wired' or 'connected' and the world becomes more tightly interconnected, network security becomes more important. Network security is the process of preventing and detecting unauthorized use of your network. We begin this chapter by looking at the network security requirements. We then discuss the types and sources of threats there are against computer networks. We go on to consider access control methods, cryptography, firewalls, intrusion detection, and security standards.

Chapter Contents:

• 17.1 Security Requirements
• 17.2 Network Threats
• 17.3 Access Control Methods
• 17.4 Cryptography
• 17.4.1 Substitution Cipher
• 17.4.2 Transportation Ciphers
• 17.4.3 RSA
• 17.5 Firewalls
• 17.6 Intrusion Detection
• 17.7 Security Standards
• 17.7.1 IPSec
• 17.7.2 DES
• Summary
• Review Questions
• Problems

Inspec keywords: cryptography; computer networks; firewalls

Other keywords: access control methods; cryptography; intrusion detection; security standards; network managers; banking; investing; firewalls; network security; computer networks; security measures

Subjects: Data security