The main types of network security devices include firewalls, intrusion protection systems (IPS), unified threat management (UTM) systems, network access control (NAC), email security gateways, web application firewalls (WAF), and VPN gateways. Each layer serves a distinct role in reducing vulnerabilities and reinforcing the security of systems, networks, and data. This layered methodology—commonly referred to as defence-in-depth —ensures that if one control fails, other safeguards remain in place to mitigate the risk. By employing multiple graded protection stages, potential unauthorized access and data breaches can be diffused. Guidance on how to choose, configure and use devices securely. Implementing effective authentication on smartphones, tablets, laptops and desktop PCs. Guidance on some common approaches to system administration architectures.
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