Rstp parameters, Rstp operation levels – Interlogix GE-DSH-73 Series User Manual User Manual
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Chapter 5: Web-Based Management
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GE-DSH-73/DSH-82 and DSH-82-PoE User Manual
RSTP Parameters
RSTP Operation Levels
The Switch allows for two levels of operation: the switch level and the port level. The 
switch level forms a spanning tree consisting of links between one or more switches. 
The port level constructs a spanning tree consisting of groups of one or more ports. 
The STP operates in much the same way for both levels. 
NOTE:
On the switch level, RSTP calculates the Bridge Identifier for each switch and
then sets the Root Bridge and the Designated Bridges.
On the port level, RSTP sets the Root Port and the Designated Ports.
The following are the user-configurable STP parameters for the switch level: 
 
Parameter
Description
Default Value
Bridge Identifier (Not user 
configurable except by 
setting priority below) 
A combination of the User-set priority and 
the switch’s MAC address. 
The Bridge Identifier consists of two parts:
a 16-bit priority and a 48-bit Ethernet 
MAC address 32768 + MAC 
32768 + MAC
Priority
A relative priority for each switch – lower 
numbers give a higher priority and a 
greater chance of a given switch being 
elected as the root bridge 
32768
Hello Time
The length of time between broadcasts of 
the hello message by the switch 
2 seconds
Maximum Age Timer
Measures the age of a received BPDU for 
a port and ensures that the BPDU is 
discarded when its age exceeds the value 
of the maximum age timer. 
20 seconds
Forward Delay Timer
The amount time spent by a port in the 
learning and listening states waiting for a 
BPDU that may return the port to the 
blocking state. 
15 seconds
 
 
