[Ubuntu]Ubuntu11.10 Firewall

Linux doesn't need to install antivirus,you can open the firewall to protect your computer.
There are two ways to open firewall in Ubuntu 11.10
1.GUI firewall configuration
Search firewall in Software center and install  firewall configuration

Then,you can  open the firewall and modify your firewall setting by using firewall configuration

2.Open firewall by terminal

 To open:                                                Close:                                                To check your firewall status:

 sudo ufw enable                                    sudo ufw disable                               sudo ufw status

 To open a port:                                      close an opened port:

 sudo ufw allow 22                                  sudo ufw deny 22

Although Linux doesn't need to install antivirus,you can install it to check your whether has virus in windows.
Search ClamTK in Software Center and install it OR you can install AVG linux edition manually.

To improve your security,you can install SELinux.