Low-cost Security Improvements

Doing it on a shoestring basis:

Document and publish what you expect your system support staff to do with respect to security.
Configure your border routers to deny all unnecessary incoming traffic.
Identify and protect your most valuable assets first.
Secure the perimeter and core systems.
Simplify.
Use freeware vulnerability assessment tools to conduct a self-assessment of your network and computers. Publish the results internally to management staff.
Install freeware host and network based auditing and traffic analysis tools on critical hosts.
Monitor output and logs on a daily basis.

Free Tool Repositories