IP video systems are extremely flexible. Essentially all that is required for operation is a power source and a network connection.
Power sources for the cameras can be part of the standard electrical grid serving the facility, or there are also options for delivering Power over Ethernet. In the PoE environment, electrical power to run the camera is supplied over the same cable that connects the network.
Because some cameras are also wireless capable, it is possible to connect them to a power source such as a battery or solar array and transmit video to a wireless access point.
This means that a camera can be deployed temporarily, or even mounted on a moving platform, provided power is available and the access point stays in range. This makes event security or "roaming" surveillance practical for large facilities or open areas where a wired camera would be too expensive. It also presents the possibility of "virtual presence" allowing a remote viewer to look at a piece of equipment or an area of interest in real time.