Small, low cost cameras for CCTV have been used for decades in banks, casinos, etc. where constant monitoring is required. Closed-circuit television (CCTV) is the use of video cameras to transmit signal to a specific, limited set of monitors as opposed to open broadcasting (source: http://en.wikipedia.org/wiki/Closed-circuit_television)
The goal with these systems is to keep bandwidth low while also capturing any unusual events. For instance, if there is a person walking by, the camera may just capture 2 frames of the person. It may be difficult to see in which direction the person was going but provide confirmation that a person was there. While a large field of view is required to cover a wide area, usually the locations of where an event may occur is known such as an entrance or exit, somewhat limiting the focus area. CCTV cameras have a maximum resolution of 2 Megapixels and more resolution is gained by adding cameras. They offer a simplified system design as lens control is included.
As higher performance cameras (industrial or machine vision-type cameras) have come down in price, new types of surveillance have become possible. High-end industrial cameras with minor modifications for outdoor use can offer very clear images for identification possibilities and significantly longer detection ranges. These imaging systems can allow tracking of an object rather than just detection of an object or movement. They also offer greater abilities when the expected location of an object is unpredictable. Global security or high-end surveillance are more recent terms and refer to many different applications beyond object recognition.
For example, high-end surveillance systems at a port can monitor for a variety of issues. If a ship coming in hits a dock and does damage, a high-performance camera can read the identification of the ship and enable zooming in to document even subtle damage to the dock.
Another example for the advantages of higher quality cameras is border control. Borders are very long and require a lot of resolution. Many of these systems have nice features where when an incident happens, there is a switch into higher resolution mode to save on bandwidth during other times. Because these systems are used outdoors, industrial cameras will have a longer lifetime. CCTV cameras often have moving parts that would degrade quicker in extreme temperatures.
High-performance industrial cameras with functionality for adjusting to changing light conditions (automatic exposure control, etc.) can give the image system designer a lot of flexibility such as control of the depth of field for high-end surveillance systems. The higher resolutions and image quality can improve identification capabilities and enable new global security applications.