I have just installed Cisco 1721 on a public network ( internet connectity ) for a small office i have been given 20 ips from my ISP to use .
As of now i have done a NAT between my office ip and ISP ips .
What security measures I can undertake to gaurd against any untoward incident on my office network. please give security settings.
Can any one inform me on how PAT ( Port Address Translation works ) and how to do it , is PAT more secure than NAT.