Rooting K9608-2W
Let's say you have one of these and you want shell access for some reason, like setting the date & time programatically. By adding a couple magic files to a USB mass storage device, connecting it to your NVR and rebooting, you will be able to login via telnet.
Login to the web user interface of your NVR, go to Settings (wrench and screwdriver icon). If you see the following info listed in the DevInfo tab, then these instructions should work for you. This may work with other software versions too but no promises.