IP-based cameras are not restricted to the lower resolution of analog cameras. A 5-megapixel IP camera gives you ten times more detail than an analog 4CIF camera.
Many analog cameras have a maximum resolution of 704 x 480 pixels (4CIF), but IP cameras can provide much higher resolutions, including HDTV (720p/1080p) and even up to 5 megapixels (2560 x 1920). This means you can either cover a much larger area, or get a highly detailed image to meet more demanding identification requirements.
IP-based cameras also offer several different aspect ratios, making it easier to capture wide scenes and allowing you to focus your coverage where it is most needed.