Bandwidth Simulator
When you create a streaming media presentation that targets audiences at
different connection speeds, it's important to test your presentation at each
target speed. Using the RealOne Player bandwidth simulator, you can use a
single RealOne Player to evaluate how your presentation works at streaming
speeds.
Streaming Your Presentations
The bandwidth simulator works only with clips that are streamed. It does not
function when you play clips from your local computer. Although you can use
a Web server, using Helix Universal Server (or an earlier version of RealSystem
Server) is recommended for testing if you plan to stream to your audience over
RTSP. If you do not have access to a Helix Universal Server used to stream
actual content, you can download and install the
free version of Helix Universal Server Basic on your desktop computer from
this Web address:
http://www.realnetworks.com/products/server/index.html
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Tip:
By using Helix Universal Server on your local computer,
you can test a presentation at any bandwidth, even at speeds
higher than your computer's actual network speed.
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Installing the Bandwidth Simulator
Installing Helix Producer Plus adds the bandwidth simulator to RealOne
Player automatically. You should therefore download and install the latest
version of RealOne Player from http://www.real.com. Helix Producer Plus is
available for purchase and download at this Web page:
http://www.realnetworks.com/products/producer/index.html
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Note:
The bandwidth simulator is not included with the free
version of Helix Producer.
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Tip:
If you install RealOne Player after you install Helix
Producer Plus, you can install the bandwidth simulator by
running the Bandwidth_Simulator_Setup.exe program in the
Helix Producer Plus installation directory.
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Running the Bandwidth Simulator
Once you have installed the bandwidth simulator and have a Helix Universal
Server with content to stream, you can use the bandwidth simulator in
RealOne Player.
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To use the bandwidth simulator:
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- Start RealOne Player and request your presentation from Helix Universal Server's content directory with File>Open. If you installed a copy of Helix Universal Server on your desktop machine, you typically can use the local host address to request the presentation, as shown in this example:
rtsp://127.0.0.1/my_presentation.smil
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- Give the RealOne Player command Tools>Bandwidth Simulator to display the bandwidth simulator.
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Tip:
This command appears in the menu only after you've
requested streaming content.
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- Click and drag the bandwidth slider to the bit rate at which you want to test your presentation. The figure below shows the simulator set to an average streaming speed of 64 Kbps.
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Note:
Choosing another bandwidth automatically restarts the
presentation as long as Restart on Bandwidth Change is
checked.
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- Optionally, you can simulate one, five, or ten percent packet loss if you want to test how the presentation runs on a network, such as the Internet, where IP packets may be lost. A good Internet connection will lose no packets, or only a small percentage. The top range of 10 percent loss represents a severely bad connection.
- Monitor the presentation playback to ensure that it works properly for your chosen audience target.
Using the SMIL Test File
You can use the file bandwidth_simulation_test.smil
in the samples/simulator
directory of this online manual to test the bandwidth simulator. The file uses
a <switch>
group with inline text clips that report the approximate bandwidth
of the simulated connection. Copy this SMIL file (it has no externally linked
clips), to the content directory of your Helix Universal Server and request it
through RealOne Player using an RTSP URL like one of the following:
rtsp://helixserver.example.com/bandwidth_simulation_test.smil
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rtsp://127.0.0.1/bandwidth_simulation_test.smil
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