System Updates: Regular software updates are key to ensuring system security. Operating system vendors and software manufacturers are issuing patches and fixes to fix security vulnerabilities found.

Firewall: A firewall is a mechanism that controls network traffic to protect the system from unauthorized connections. It can block unwanted traffic, control access to network resources and monitor network activity.

Privilege restrictions: Limiting the privileges of system users can help minimize the risk of attack. Users should be given only those permissions necessary to perform their tasks, and redundant permissions should be restricted.

Strong passwords: Requiring strong passwords for users is a basic security principle. Strong passwords should contain a combination of letters, numbers and special characters, and should be changed regularly.

Remove unnecessary applications and services: Only necessary applications and services should be present on the system. Unnecessary or unused software can be potential entry points for attackers.

Monitoring and recording: Systems should be monitored to detect suspicious activity and attempted security breaches. Event logging can help identify possible incidents and track the activities of suspicious users.