Port Priority
A relative priority for each
port –lower numbers give a higher priority
and a greater chance of a given port being
elected as the root port
32768
Port Cost
A value used by STP to evaluate paths –
STP calculates path costs and selects the
path with the minimum cost as the active
path
19-100Mbps Fast Ethernet ports
4-1000Mbps Gigabit Ethernet ports
Default Spanning-Tree Configuration
Feature
Default Value
Enable state
STP enabled for all ports
Port priority
128
Port cost
19
Bridge Priority
32,768
User-Changeable STA Parameters
The Switch’s factory default setting should cover the majority of installations. However, it is advisable to keep the
default settings as set at the factory; unless, it is absolutely necessary. The user changeable parameters in the
Switch are as follows:
Priority
– A Priority for the switch can be set from 0 to 65535. 0 is equal to the highest Priority.
Hello Time
– The Hello Time can be from 1 to 10 seconds. This is the interval between two transmissions of
BPDU packets sent by the Root Bridge to tell all other Switches that it is indeed the Root Bridge. If you set a Hello
Time for your Switch, and it is not the Root Bridge, the set Hello Time will be used if and when your Switch
becomes the Root Bridge.
NOTICE:
The Hello Time cannot be longer than the Max. Age. Otherwise, a configuration error will
occur.
Max. Age
– The Max Age can be from 6 to 40 seconds. At the end of the Max Age, if a BPDU has still not been
received from the Root Bridge, your Switch will start sending its own BPDU to all other Switches for permission to
become the Root Bridge. If it turns out that your Switch has the lowest Bridge Identifier, it will become the Root
Bridge.
Forward Delay Timer
– The Forward Delay can be from 4 to 30 seconds. This is the time any port on the
Switch spends in the listening state while moving from the blocking state to the forwarding state.
NOTICE:
Observe the following formulas when setting the above parameters:
Max. Age _ 2 x (Forward Delay - 1 second)
