I think you will find that one of both of these ports are for the "heart beat" if your ISP can't detect these or they aren't responded to, then the isp will believe that you modem has been disconnected or not working and you will loose your ip and connection. You should be able to confirm this with the ISP's technical support so you can't secure anything that isn't directly needed by you or them.
Dallas -----Original Message----- From: Mike Marcus [mailto:mmarcus@;nelsonpub.com] Sent: Saturday, 2 November 2002 4:53 AM To: [EMAIL PROTECTED] Subject: Cable Modems Need Open Ports? I was "playing" with setting on my router that is connected to a cable modem (Comcast is the ISP). After blocking incoming (from wan) UDP and TCP ports 53 and 59 the router lost its external IP. Any ideas? Thanks, Mike
