From the desktop:
A camera, microphone & speakers or a headset, internet access and your pc or laptop either loaded with Video Conferencing software or access to a hosted Video Conferencing service.
OR an executive desktop Video Conferencing system with an IP or ISDN connection.
From the meeting room:
Each site participating in the Video Conference will require, as a minimum, a camera, a codec, a microphone, a speaker, a monitor and an IP or ISDN connection. The camera and microphone capture the image and sound, the codec converts the video and audio into a digital signal, encodes it and sends it out. The codec at the other end decodes the signal and distributes the video and audio to the monitor and speaker.