Appendix A - Bandwidth Considerations In Qsx; Overview - Polycom QSX Administrator's Manual

Appendix A – Bandwidth Considerations in QSX

Overview

The QSX 2.0 offers a number of bandwidth options that allow you to optimize its use for
your particular environment. The flowchart below is designed to serve as a guide for
making the proper bandwidth configurations.
This flowchart assumes that you are starting with an idea of how you want to use the
QSX (e.g.- in a Stand Alone mode to share content with web viewers only or in a mixed
environment with other QSX units and web viewers). It also assumes you have a general
idea of the bandwidth that you have available. Based on that information, you can use
this chart to determine the performance with various numbers of participants and what
settings you need to configure on the Web Admin page of the QSX.
Usage Usage Bandwidth Bandwidth
High Bandwidth High Bandwidth
1920 Kbps 1920 Kbps
QSX to web- QSX to web- Med Bandwidth Med Bandwidth
viewers only viewers only 512 Kbps 512 Kbps
Low Bandwidth Low Bandwidth
384 Kbps 384 Kbps
How are you How are you
going to use going to use
the QSX? the QSX?
High Bandwidth High Bandwidth
1920 Kbps 1920 Kbps
QSX to QSX QSX to QSX
& web- & web-
viewers viewers
Low Bandwidth Low Bandwidth
512 Kbps 512 Kbps
Note: In the above diagram, "Transition Speed" is the average number of seconds it takes
for a new image to refresh on a meeting participant's screen. These times are all
approximate. Actual times are based on actual bandwidth and amount of network traffic.
This chart was based on a PC input resolution to the QSX of 1024x768. The QSX was
configured for no scaling (1024x768) for H.323 connections and 800x600 for web
viewers.
Performance Performance
# of web viewers # of web viewers 1 1 5 5
Transition Time (sec) 1-3 Transition Time (sec) 1-3 3-5 3-5
# of web viewers # of web viewers 1 1 5 5
Transition Time (sec) 3-5 Transition Time (sec) 3-5 7 7
# of web viewers # of web viewers 1 1 5 5
Transition Time (sec) 3-7 Transition Time (sec) 3-7 7-16 7-16
# of web viewers # of web viewers 1 1 5 5
Transition Time (sec) 1-3 Transition Time (sec) 1-3 2-6 2-6
# of QSX units # of QSX units 1 1 2 2
Transition Time (s) Transition Time (s) 0.25 0.25 0.25 0.25
# of web viewers # of web viewers 1 1 5 5
Transition Time (sec) 3-5 Transition Time (sec) 3-5 6-15 6-15
# of QSX units # of QSX units 1 1 2 2
Transition Time (s) 0.25 Transition Time (s) 0.25 0.25 0.25
52
QSX Settings QSX Settings
(Web Admin Page) (Web Admin Page)
Bandwidth Sharing Mode: Bandwidth Sharing Mode:
10 10
Max Average Tx: Max Average Tx:
6-8 6-8
Max Average Rx: Max Average Rx:
Bandwidth Sharing Mode: Bandwidth Sharing Mode:
10 10
Max Average Tx: Max Average Tx:
12 12
Max Average Rx: Max Average Rx:
Bandwidth Sharing Mode: Bandwidth Sharing Mode:
10 10
Max Average Tx: Max Average Tx:
7-22 7-22
Max Average Rx: Max Average Rx:
10 10
Bandwidth Sharing Mode: Bandwidth Sharing Mode:
6-8 6-8
Max Average Tx: Max Average Tx:
Max Average Rx: Max Average Rx:
4 4
0.25 0.25
>5 web >5 web
viewers not viewers not
Bandwidth Sharing Mode: Bandwidth Sharing Mode:
recommended recommended
at this at this
Max Average Tx: Max Average Tx:
bandwidth bandwidth
Max Average Rx: Max Average Rx:
4 4
0.25 0.25
Bandwidth Bandwidth
1024 1024
1024 1024
Bandwidth Bandwidth
512 512
512 512
Time Sharing Time Sharing
384 384
1024 1024
Bandwidth Bandwidth
1920 1920
1920 1920
Bandwidth Bandwidth
512 512
512 512