What is network security? Definition, methods, jobs & salaries

Network security is the practice of preventing and protecting against unauthorized intrusion into corporate networks. As a philosophy, it complements endpoint security, which focuses on individual devices; network security instead focuses on how those devices interact, and on the connective tissue between them.

The venerable SANS Institute takes the definition of network security a bit farther:

Network security is the process of taking physical and software preventative measures to protect the underlying networking infrastructure from unauthorized access, misuse, malfunction, modification, destruction, or improper disclosure, thereby creating a secure platform for computers, users, and programs to perform their permitted critical functions within a secure environment.

But the overall thrust is the same: network security is implemented by the tasks and tools you use to prevent unauthorized people or programs from accessing your networks and the devices connected to them. In essence, your computer can’t be hacked if hackers can’t get to it over the network.