List what you judge to be the five most important hardening steps for each of the following component levels. For each of the steps you list, provide a brief description of what security or protection it provides. If you include a hardening step in more than one component type, also provide information on how it differs in each use.

Top 5 Hardening Steps for:

Operating system:

Routers and switches

Host computers

Dedicated servers (DHCP, Database, etc)

SAN/NAS