Defense in Depth is a strategy used in cybersecurity where multiple layers of security controls (defense) are placed throughout an information technology (IT) system. Its intent is to manage risk with diverse defensive strategies, so if one layer of defense turns out to be inadequate, another layer of defense hopefully prevents a full breach.
Employ multiple layers of security measures so if one mechanism fails, others are already in place to prevent an attack.
Have multiple systems that can do the same task. If one system fails, others can take over.
Use security controls from different vendors to minimize the impact of a single vulnerability across multiple systems.
Keep details of the environment and security controls undisclosed to add an extra layer of protection.
Defense in depth is not just about technology but also includes people and processes.
Separate the network into segments to contain potential attacks and prevent lateral movement.
Use firewalls to control incoming and outgoing network traffic based on an organization’s previously established security policies.
Monitor network traffic for malicious activities or policy violations and report it to a management station.
Help protect against malware which can be used to gain unauthorized access to a system.
Keep all systems, applications, and security controls updated with the latest patches.
Use two or more different types of credentials for authentication to add an extra layer of security.
Train users about security best practices and how to spot potential attacks, like phishing.
Monitor and log all activities on the network and regularly audit these logs.
Have a plan in place to respond effectively to security incidents.
For more information on Defense in Depth and to stay updated with the latest strategies and practices, refer to the following resources:
Remember, no single strategy or product can completely secure an organization. Defense in Depth provides a comprehensive approach to security by using a balanced combination of administrative, technical, and physical security controls.