Network Security, Firewalls, and VPNs, 3rd Edition

What Is Network Security?

Network security is the control of unwanted intrusion into, use of, or damage to communications on a computer network. This includes monitoring for abuses, looking for protocol errors, blocking nonapproved transmissions, and responding to problems promptly and accurately. Network security is also about supporting essential communication necessary to the organization’s mission and goals, avoiding the unapproved use of resources, and ensuring the integrity of the information traversing the network.

Network security includes elements that prevent unauthorized access and actions while supporting desirable activities, such as accessing customer records or managing inventory. This is hard to do efficiently, cost effectively, ...