Someone asked you how video conferencing works? The most basic answer is that with at least 2 screens, microphones and devices to transmit live images/video involved, communication through video conferencing is achieved.
Main components required for the system are; video input/output, audio input/output, data transfer (could be an analog/digital network, LAN or the internet) and finally the computer which links the components, maintains data connection via the network and is responsible for the constant compressing and decompressing.
The core technology used in this system is the digital compression of audio (inputted using a microphone) and video (inputted using a camera) streams in real time. The device necessary for this compression is commonly known as the codec (coder/decoder) that produces a digital stream of 1 s and 0 s which are to be transmitted through Internet Protocols (IPs) or any other digital network. As the transmitted digital stream reaches its destination it is decompressed to be seen on monitors and heard from speakers.
As seen in the chart above, the Real Time Protocol (RTP) and Real Time Control protocol (RTCP) work together to provide real time transmission of audio and video stream. Both protocols use the User Datagram Protocol (UDP) as their transport layer underlying protocol.
The clarity of the video or audio greatly depends on the compression ratio (the higher the better) and also on the available bandwidth and connection speed. An example would be a ratio of 2.1 which is like staring at a still picture while talking to the person. In comparison, having a ratio of 100.1 is almost like chatting with someone in real time such that the voice and video is neither choppy nor sticky. On average, the compression rate in video conferencing is in the range of 13.1 to 17.1
In addition to voice and video calling, video conferencing softwares include other useful features like simultaneous messaging, file transfer and screen recording. Currently, popular programs used for social communication are Oovoo, Skype and Google Talk.
I believe that this system redefines what it means to be part of this modern world. It merges the realism and time-sensitive nature of the standard telephone with the ability to actually see the person on the other end of the communication line. I have been using these programs for over 3 years now and more frequently after moving to the US to remain in touch with family and friends. It is slowly becoming a significant part of people’s lives who are always on the go for both professional and personal reasons.
Wikipedia contributors. “Videoconferencing.” Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 27 Apr. 2013. Web. 27 Apr. 2013.
Alvarenga, Richard. How Does Videoconferencing work? 27 April 2013.