Network security refers to the technologies, processes, and policies used to protect networks, network traffic, and network-accessible assets from cyberattacks, unauthorized access, and data loss. Organizations of all sizes need network security to protect their critical assets and infrastructure.
Modern network security takes a layered approach to protect the many edges of the network and the network perimeter. Any element of the network could be an entry point for attackers—endpoint devices, data paths, applications, or users. Because organizations face numerous potential threats, it is common to deploy multiple network security controls designed to address different types of threats at different layers of the network and infrastructure. This is called a defense in-depth security approach.