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What exactly is Internet television (TV)? There is no agreement on a definition.
It comes with different names—web TV, IPTV, enhanced TV, personal
TV, and interactive TV, for example—which signify slightly different
things. At the lower end of complexity, it is merely a narrowband two-way
Internet-style individualized (“asynchronous”) channel that accompanies
regular one-way “synchronous” broadband broadcast TV or cable. This
Internet channel can provide information in conjunction with broadcast
programs, such as details on news and sports, or enable transactions (including
e-commerce) in response to TV advertisements. This is known as
“enhanced TV.” At the other end of complexity is a fully asynchronous
two-way TV, with each user receiving and transmitting individualized TV
programs, including direct interaction in the program plot line. In between
is one-way broadband with a narrowband return channel that can be used
to select video programs on demand (VOD). What Internet TV is today and
can be in the future forms the context of this book. |
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