The main difference is how the images are sent. Analogue systems use standard base band formats to send the video signals down coaxial cable. The images are then sent to a DVR (Digital Video Recorder) where they are then digitised and stored locally onto a hard-drive. With an IP system the information is sent digitally over network cabling and is then received by an NVR (Network Video Recorder). In terms of video quality, IP systems currently have the capacity for much better camera resolutions due to the limitations in using coaxial cabling on analogue systems but there are some new coaxial based technologies, mainly HDCVI, that are allowing for much higher HD resolutions to be sent down coax.