Digital Signal Processing Reference
In-Depth Information
is far more ubiquitous than video conferencing. The video
conferencing options of H.323 feature video compression using
H.264.
Another standard known as session initiation protocol (SIP)
has become very popular for packet-based audio and video
conferencing. SIP focuses on the messaging needed to set up,
maintain and tear-down joint sessions between multiple users.
The actual transport of the audio, video and data is over RTP. SIP
also has additional features, such as instant messaging, and is
generally more flexible than H.323.
Despite efforts to encourage the adoption of video confer-
encing as a primary means of holding long distance meetings,
audio conferencing remains far more prevalent. However, live
sharing of joint data or presentations in conference calls using
technology like WebEx
or Office Communicator has become
commonplace in the business world, leveraging the capabilities
of SIP.
