Video Conferencing Standards, Protocols and Terminology

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Video conferencing can be defined as a real-time
video session that takes place between two or
more users who reside in different locations.
This technology together with numerous functions
facilitate virtual meetings with video/audio
enabled. There are many brands in the market
which are specialized in creating video software
but very few can create highly productive and
advanced ones like ezTalks. Videoconferencing is
very useful as it helps users to schedule
meetings, invite participants, record sessions,
and share and even make presentations.
Furthermore, many users can actively take part in
a running session at the same time.
With video conferencing defined, here is some
information on the video conferencing standards
and protocol used in video conferencing. Video
conferencing can be run across two types of
networks i.e. packet switched and circuit
switched. Circuit switched The characteristics
of circuit switched include the following
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• ?The network has a bandwidth that is guaranteed
  through it.
• ?There is no sharing of connection after
  connection is established.
• ?A circuit can be brought up on demand through
  the network.
• ?A single bit stream is used in sending
  information.
• Packet switched
• The characteristics of packet switched include
  the following
• ?Bandwidth is not guaranteed.
• ?There is sharing of the bandwidth.
• ?Circuits are not available on demand are built
  as required.
• ?Information has to be broken down into packets
  before it is sent.
• The International Telecommunications Union (ITU)
  is the body which is responsible for developing
  global recommendations for telecommunications.
  H.3xx are considered to be the umbrella
  recommendations that are specific to
  videoconferencing. The recommendations are used
  to reference other recommendations which are
  inclusive of the protocols for audio/video,
  control, signaling and multiplexing.
• The main video conferencing standards and
  terminology utilized include the following

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5. Showing Data - The standards in use here are
H.239 and T.120. H.239 splits bandwidth between
a second video source and the conferencing video.
It allows participants to connect their PCs to
the 2nd video stream so as to share their
computer screens with the whole conference. The
main H.3xx recommendations include H.320, H.321,
H.323, H.324 and H.310. Video conference meeting
protocols of concern are the H.323 and the
H.320. The H.323 The H.323 can be defined as an
International Telecommunications Union standard
which describes the equipment, services and
protocols which are necessary for multimedia
communications. This is inclusive of d data,
video and audio on networks that lack guaranteed
Quality of Service. The main network components
of the H.323 are multipoint control unit (MCU),
gateway, gatekeeper (optional) and the mandatory
terminal. The audio standards for the H.323 are
G.711, G.722 and G.728. The video standards for
the H.323 are H.263, G.722 and H.264. The data
standard for H. 323 is H.239. The control
standards for the H.323 are H.225, RAS, Q.931 and
H.245. The H.320 The H.320 is one of the video
conference meeting protocols. It defines the
manner in which circuit switched networks are
utilized in video communications. Integrated
Services Digital network (ISDN) is the most
common circuit switched network. This standard
includes the signaling mechanisms for ISDN and
the way video, voice as well as other r payload
are transmitted over its interface. This
standard is an umbrella for many other standards
that have been adopted by the key manufacturers
of equipment for video conferencing. G.711 Audio,
H.261 Video, H.221 Packaging, H.242 Handshaking
and H.230 Frame-synchronous Control.
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The audio standards include G.711, G.722,
G.722.1, G.723, G.728, G.729 and G.703. The
video standards include H.261, H.263 and H.264.
The communications standards include H.221,
H.223, H.224, H.225, H.230, H.231, H.233, H.234,
H.242, H.243, H.244, H.245, H.281 and
H.331. Protocols for data collection are defined
by the family of recommendations called T.120.
The recommendations that fall under it include
T.121, T.122/125, T.123, T.124, T.125, T.126,
T.127 and T.128. SIP SIP is the acronym for
Session Initiation Protocol. This protocol was
developed for the purpose of initiating,
modifying as well as terminating all interactive
multimedia user sessions like voice, video,
instant messaging, online games and virtual
reality. It functions to provide each and every
call processing features and functions of
PSTN. SIP is strictly for conveying signals. It
doesnt carry video, voice or even streaming
information, SIP simply sets up and allows the
transfer of information. There are 6 kinds of
SIP requests (signaling messages) i.e. Invite,
Acknowledge, Options, Bye, Cancel and
Register. The information outlined above is not
exhaustive as it has not delved into voice chat
protocols in video conferencing. This is not to
discount the importance of a voice chat protocol
in the functioning of the technology. Conclusion
The above video conferencing standards and
protocol used in video conferencing give us the
background knowledge on how the convenient
technology works. https//www.eztalks.com/video-c
onference/video-conferencing-standards-protocols-t
erminology.html