2. Overview of the technology

A complete videoconference system consists of some basic components, some common (and necessary) additional equipment and some extra additional and useful peripherals. The basic components of a videoconferencing system are:

• Codec - the central unit that compresses outgoing and decompresses incoming video signal
• Digital camera - records pictures from your room
• Microphone - records the sound in your room
• Monitor with loudspeakers - see and hear the far end part(s)

Common additional peripherals:

• Ordinary blackboard/whiteboard or flipover
• Document camera
• VHS/DVD-player
• Stationary PC

Additional peripherals:

• Laptop
• Digital whiteboard
• Tablets
• More digital cameras
• Video projector(s)

Please have a look at the following pictures

	Figure 1. A trolley (on wheels) with two monitors, digital camera and codec (hidden).
	Figure 2Here is a document camera, where you can show the other locations figures and tables from a paper or a book. Even 3-dimentional objects can be shown to the others.
	Figure 3. The lecturer is using a digital whiteboard to demonstrate properties of a mathematical 3-dintional object.
	Figure 4.Here is the table version of the digital whiteboard, a so-called tablet.

Moreover have a look at the following video clips. The use of some peripherals is demonstrated here