I would not buy a switch at this time. I would first connect a computer to one of the ports in the router from your ISP. Once you have internet connection on that computer I would run ipconfig /all on the command line. Look for your gateway and make a note of it. Open your browser and in the URL put the IP address of your gateway (the ISP router) if asked for a user name and password try admin admin or nothing or a combination of both. If you are able to get into the router look to see if it is in bride mode. Most of the time the routers from the ISP are in bridge mode. If so then it is basically transparent to the networks and all you have to do is on the Linksys router put the IP of the DVR in the DMZ of the router. Also you want to setup DDNS because your public IP address may change and then you cannot connect to the DVR. Sometimes even tough the DVR is on the DMZ you may still need to forward the TCP and UDP ports that the DVR is using to the IP address of the DVR in the router. Hope this helps
