Question 7

Host isolation is essential to ensure a device is inaccessible to a network-connected resource.

Host isolation effectively restricts a device's connectivity to the network, ensuring that it cannot communicate or be accessed by any other network resources. This method is crucial for maintaining security and preventing unauthorized access.

A) Disablement of unused services

While disabling unused services is a good security practice to minimize potential attack vectors, it does not guarantee that a device remains inaccessible to network-connected resources. A device can still be connected to the network even if certain services are disabled, which means it may still be vulnerable to network access.

B) Web application firewall

A web application firewall (WAF) protects web applications by filtering and monitoring HTTP traffic, but it does not isolate devices from the network. It primarily serves to defend against web-based attacks rather than ensuring a device's complete inaccessibility from network resources.

C) Host isolation

Host isolation is the most effective option for ensuring that a device is inaccessible to network-connected resources. By isolating a device, it is removed from the network, preventing any communication with other devices or resources, thus enhancing security.

D) Network-based IDS

A network-based intrusion detection system (IDS) monitors network traffic for suspicious activity and potential attacks. However, it does not provide isolation for devices; therefore, it does not ensure that a device remains inaccessible to other network resources.

Conclusion

Host isolation is the definitive correct answer as it directly addresses the requirement of making a device inaccessible to network-connected resources. Other options, although relevant to security, do not provide the same level of protection against unauthorized access as isolation does. Thus, selecting host isolation is crucial for maintaining device security in a networked environment.