I have a LAN network behind a router/firewall which in turn goes to a cable modem. My cable IP has been blacklisted on 3 spam services. I need to monitor port 25 outbound traffic on my Netgear router. The router offers little or no monitoring abilities. Is there a software solution out there that anyone knows of that can monitor the internal or cable router for outbound SMTP traffic? I need something that is simple to use and will give me alerts when port 25 is flooded. I have a suspicion that one of the client pc's in the office started spamming out port 25. I cannot shut down port 25 because we have a legitimate fax server that pushes out faxes to internal users via email. Please advise.