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TYPES OFWEBCASTING 679and Netscape. Audio, graphics, and Web pages are sent
automatically to the users’ e-mail boxes.
The push and pull technologies work together to pro-
vide consumers effortless access to information of inter-
est to them. Pull technologies use software to pull infor-
mation for the consumer from the Internet. Consumers
can set up their own selections, or the intelligent software
agents can search out information that consumers would
be interested in. Amazon.com, for example, has pull tech-
nologies that remembers the products consumers have
purchased in the prior visits and pull information of sim-
ilar products to the user on the next visit.
The greatest benefits of using the push technologies
is that consumers can download programs, receive news
updates, and interact with the webcaster in different for-
mats such as audio, video, text, and graphics without ac-
tively searching for the information. It brings “intelligence
and efficiency to the distribution of all kinds of informa-
tion, giving webcasters more control over what users see
and when” (Miles, 1998, p. 24). Push technologies pro-
vide effortless reception of materials with little consumer
knowledge requirement and save consumers the time to
find information on the Internet.
The latest development in push technologies is to
become more interactive and automatic. Webcasters in-
creasingly provide information based on users’ past
behaviors and their response to previous information.
Editors are seldom used to sort or filter content. Some
inherent problems of push technology surround how
much information should be provided to the audience and
the potential invasion of Internet users’ privacy by pulling
intelligence from users’ past choice and preferences
without their explicit consent. Users are increasingly in-
tolerant of unsolicited materials that webcasters send
without permission. They will tune out these materials
and the effectiveness of pushing materials is thus greatly
diminished.On-Demand
On-demand webcasting refers to the webcasting of
content based on the request of the consumer at the time
of use. The webcaster supplies the media contents in a
catalog or playlist for consumers to choose. The term
on-demand refers to the ability of the user to control the
scheduling and appearance of the webcast. The audience,
instead of the webcaster, chooses when and what to view.
In many on-demand webcasts, additional features are
provided, such as instant replay; no waiting for rewind or
fast forward during live events; interactive devices such as
question and answer, chat rooms, product or service order
forms, multiple camera angles, and zooming in and out
the picture. On-demand webcasting’s greatest attractions
are the convenience to the consumer and the audience’s
ability to retrieve information or content that has been
missed. There are both business and consumer uses of
on-demand webcasting. Business and governments are
already making use of on-demand webcasting to provide
training and product information for employees, suppliers,
and customers. Intel, for example, frequently uses web-
casts to provide live seminars to prospective customers.
On-demand webcasting can be downloadable or show
the content in real time. If the webcast is downloadable,compressed files are downloaded to the user’s computer
and a media player is used to play back the files (also
called HTTP streaming). On-demand can also use real-
time streaming to broadcast the content directly from a
server as selected by the user so that the user can instantly
watch or listen to it. No file storage or cache is involved
in streaming (Real Networks, 2002). Users cannot store,
copy, or retransmit the content because the stream never
touched the local drive of the user and the data are dis-
carded after playback. Hence the content owners can pre-
vent piracy of their content. In addition, on-demand can
extend webcasters’ reach, increase the value of their media
contents over a long period of time, and save bandwidth
as well because not everyone connects at the same time
(Mack, 2002).Live Streaming
Streaming is an Internet data transfer technique that does
not need to wait for the whole file to download to a user’s
computer before playback begins (Mack, 2002). It involves
three different types of software: (1) anencoder,which
converts an audio or video signal from an analog format
to a digital format and compresses the digital files for
transmission over the Internet; (2) aserver,which deliv-
ers data streams to audience members; and (3) aplayer,
which viewers use to watch or listen to the streaming me-
dia. The content of webcasts using streaming technologies
can either be live or on-demand. In live streaming web-
casts, the broadcast schedule is fixed so that time-sensitive
contents can be delivered instantaneously to users. Users
must follow the schedule to receive the content. Live web-
casts require multiple streaming servers to reduce the load
of each server and to minimize the chance of crashing a
server by too many users tuning in at the same time.
In a live streaming webcast, users can also interact with
the event as it is happening such as clicking on a picture of
a car to view its details or change its color. Although many
refer “streaming” to the retransmission or repurposing of
traditional broadcast content such as television and radio
signals on the Web, streaming is not limited to retrans-
mission. It can also be original content transmission with
intent to reach the public. Webcasting using streaming
technology can pick up viewers or listeners from areas
around the world.
The ability to squeeze the audio and video into a stream
is the basis of streaming technologies. These technologies
use software to compress the signals for transmission and
decompress the signals for display on the viewer’s screen
in the correct order continuously so that the viewer can
view the content almost instantly. It is very important that
the signals are reassembled in the correct order during the
decompression process. Any gaps in between will make
speech and video incomprehensible. For successful web-
casting using streaming technology, the webcaster needs
to secure a powerful high-speed server to deliver the sig-
nal, and they need enough bandwidth to enable multiple
users to view the program.
Multicasting can be a method to save on bandwidth
costs for webcasters. It is the ability to take one signal and
send it to lots of people through a network or over the In-
ternet. The one signal locates a device (e.g., a router) that
sends the signal to a number of computers or television