Think about what technology can inspect and filter network traffic based on the source of a request.
Consider which solution specifically targets network-level access controls rather than physical security or communication methods.
Look for the option that uses rules to identify and allow only certain computers or locations to reach the servers.
Restricting by IP address points to a network-level control.
A firewall rule can permit only specific source addresses to reach a server.
Passwords, cameras, and email encryption don't gate server access by network.

Common attack vectors