Ja sa v tomto nevyznam, ako pisem je to iba moj pocit. Ale viem ze kamos, ktory sa pripaja na net cez modem dostava do hodiny po preinstalovani windowsu varovania z Kerio firewallu ze sa niekto/nieco snazi pripojit na jeho pocitac. Pokial to povoli tak mu zacne kvikat antivirus, ze sa na disk prave zapisal nejaky zavireny subor. Mne sa za routerom nic taketo nestava.

Trochu som kvoli tebe aj pogooglil:

If it is a NAT Router it'll only stop Internet worms and BOTs. These use network protocols to look for vulnerabilities in services that open network ports such as TCP ports 135 and 445 and NetBIOS over IP and attempt to exploit those vulnerabilities.

a este aj toto:
http://www.technologyspeak.com/articles/using-your-router-to-defend-against-viruses-and-other-malicious-attacks/