OPTICODEC-PC INTRODUCTION
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For example, if you have a 100 Mbps network and you want to know how many 32
kbps streams you can support, the equation is 10,000,000 * 70% / 32000 = 2187 si-
multaneous streams.
Your required network bandwidth will be determined by your intended audience
size and whether you are using unicast or multicast streaming.
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Unicast streaming bandwidth, the most common, is the total number of simul-
taneous streams multiplied by the stream bitrate, plus some network overhead,
or:
Bandwidth (Unicast)
= (Number of Concurrent Streams) * (Stream Bitrate) + 20%
•
Multicast streaming bandwidth is simply that of a single stream plus some net-
work overhead, or:
Bandwidth (Multicast)
= (Stream Bitrate) + 20%
To ensure reliability, bandwidth projections must be based on peak usage, not aver-
age usage.
Streaming Architecture
Live Streaming
Live events, such as radio broadcasts, concerts, speeches, lectures, and sporting
events are commonly streamed over the Internet as they happen with the assistance
of broadcasting encoding software such as Orban Opticodec-PC Streaming Encoder.
The broadcasting software encodes a live source, such as studio originated audio, in
real time, and delivers the resulting stream to the server. The server then serves, re-
flects, and/or relays the live stream to media player clients.
Like a radio broadcast, a live stream provides identical, essentially synchronized con-
tent to all listeners. (The only factor that prevents perfect synchronization is varying
network latencies between the server and the various listeners.) This live experience
can be simulated with recorded content by broadcasting from an archive source such
as a playout system or by creating playlists of media on a media server.
File Streaming
With file streaming, or on-demand delivery, such as archived broadcasts, concerts,
speeches, lectures, and sporting events, each user initiates the stream from the be-
ginning, so no user ever comes in late to the stream. No broadcasting or streaming
encoder software is required. The files are encoded prior to upload to the server us-
ing software such as Orban Opticodec-PC File Encoder.
