What does host-level MTD require changes to?

Host-level MTD, or Moving Target Defense, requires changes to host resources, operating systems, and configurations. This approach aims to enhance security by dynamically changing the attack surface of computing resources, making them harder for attackers to exploit.

To effectively implement host-level MTD, modifications to host resources are necessary, as this may involve reallocating CPU, memory, or storage to support newly shifted services or configurations. Additionally, the operating system must be adapted to facilitate these changes, such as using different kernel versions or applying specific patches which can change how the system behaves and interacts with potential threats. Lastly, configurations must be tailored to ensure that defenses align with the active state of the host, including alterations to firewall rules, service settings, and user access controls.

By focusing on these aspects, host-level MTD enhances resilience against attacks, using the principle of diversity in security postures to complicate an attacker’s task. The approach does not primarily concern itself with the external infrastructure components such as network bandwidth, VPN configurations, hardware components, or application versioning, which are more closely related to wider network security strategies rather than specific adjustments at the host level.