Polycom QSX 3725-22370-001/B Manual De Usuario

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Additional Information 
Maximum Bandwidth Utilization in Low Bandwidth Environments 
Most low bandwidth connections (e.g.- DSL) are asymmetrical—transmission speeds are 
usually slower than reception speeds.  The Transmit and Receive configurations of the 
QSX 2.0 use this fact to fully utilize available bandwidth.  Look at the following 
example, where to QSX units are connected at different rates: 
 
 
Transmit Speed Receive Speed
QSX1
384Kbps
1024Kbps
QSX2
128Kbps
1024Kbps
 
 
 
 
In this case, even though the QSX2 has a slower connection, the QSX1 can still transmit 
data at 384Kbps and the QSX2 can receive it at that speed.  The extra bandwidth 
available allows you to share content with people, minimizing delays in delivering that 
content to them. 
 
Bandwidth Sharing versus Time Sharing 
The QSX allows you to choose between two different modes of bandwidth sharing for 
Web Viewers. Depending on the type and speed of connection that participants have to 
the meeting, you can use one of these modes to optimize the quality of information 
exchange. 
 
Time Sharing 
The Time Sharing mode was developed to accommodate web viewers in a low bandwidth 
environment.   
 
In the Time Sharing mode, current images will be uploaded to participating web viewers 
on a rotating basis.  For example, if 32Kbps is available for web viewing and there are 
three (3) web viewers connected to the QSX, they will, in turn, use the full 32kbps to 
upload images. 
 
No matter how many web viewers are connected, the bandwidth used by each web 
viewer will not exceed the maximum allowed value.  Moreover, each web viewer still 
works under normal bandwidth conditions. 
 
The advantage of Time Sharing is that a web viewer will have the full amount of 
bandwidth for a period of time to upload shared content.  The disadvantage is that one 
slow connection could affect the performance of the rest of the web viewers.  If, for 
example, the bandwidth allowed is 128Kpbs, but one of three web viewers has a 56Kbps 
connection, then the real bandwidth usage will be: 
 
 
 
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