point-to-point or point-to-multipoint, one-way (unidirectional, much like the
delivery method of cable television into a house) or two-way (bidirectional,
where video signals are sent upstream to be retransmitted downstream). Some
of the applications are summarized in following sections.
Media Retrieval
In this application video programming is stored in digital or analog format
and a system administrator or authorized individual users can schedule, or
“call up,” in real time, specific video programming. For example, a mathemat-
ics teacher, possibly with the assistance of a librarian or media director, can
call up a program entitled “Practical Applications of Algebra” for viewing
by the teacher’s 2:00PMalgebra class. A similar application, video on demand
(VOD)—primarily used for movies—is also becoming more mainstream with
the hospitality industry.
Video Conferencing
Video conferencing technology addresses the cost and potential inefficiencies
of live meetings. Its deployment differs by application. It can be personal video
conferencing where participants use a personal computer with a web camera.
In smart buildings the application comprises video conferencing equipment
for a typical meeting room where displays and audio equipment provide for
the exchange of video, content and audio. Most recently this type of video con-
ferencing has evolved to “telepresence.” Telepresence shows every meeting par-
ticipant in true-to-life dimensions to the point that one can read the body
language of others. Each connected telepresence location is equipped with a
duplicated surrounding, such as similar table, chairs, wall coloring, and so
on, and provides a sensation that each participant is seated around the same
table. Regardless of the type of video conferencing deployment, the audio qual-
ity between locations is critical to its success—video can embellish and enrich
the audio conversation but cannot replace it.
Distance Learning
Distance learning can be described as a specialized form of video conferencing.
Typically distance learning has an instructor in one location and a class or indi-
vidual student at another location. The application may also be augmented with
96 Smart Building Systems for Architects, Owners, and Builders