Nowadays it is essential to have a good firewall installed in your PC, as there are many dangers and attacks coming from hackers who can enter it. If you still don`t have one, then not a bad option is this iolo Personal Firewall.
With iolo Personal Firewall, apart from protecting and restricting access, you can monitor all the transfers that are contiually being done, it shows the programs/applications that ask for those transfers, and also the packets that are sent, it establishes more severe restriction rules for protection, has different levels of security, blocks certain programs, etc.
With iolo Personal Firewall you can also limit the traffic permitted for certain applications, restrict access, generate detailed reports of all access that happens (and the traffic it generates), etc. iolo Personal Firewall supports the wide majority of existing protocols.