Polycom RMX 1500 Administrator's Manual page 729

On the slider bars, red areas to the left of the blue slider buttons
indicate allocated resources and purple areas to the right of the blue
slider buttons indicate unallocated resources in the system.
Allocated Resources
When the position of a slider is changed the system calculates the
effect on the remaining system resources and adjusts the slider scales
accordingly.
For example: Decreasing the allocated CIF ports from 80 to 53, free
ports for allocation that can be used to allocate up to 135 voice ports
or 10 SD ports or 6 HD 720p ports, or any combination of the resource
types.
Allocating five Audio Only ports decreases the number of CIF ports
while allocating one SD port decreases the number of CIF ports.
4 Click OK to activate the new Resource Capacity.
Polycom RMX 1500/2000/4000 Administrator's Guide
Slider button
Decreasing CIF Resources increases the number of available
Audio Only, SD, HD720p and HD1080p Resources
Un-allocated Resources
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