User’s Manual of WSD-800 / WGSD-910/WGSD-1022C

The following are the user-configurable STP parameters for the port or port group level:

 

 

 

 

Variable

Description

Default Value

 

Port Priority

A relative priority for each

32768

 

 

port –lower numbers give a higher priority

 

 

 

and a greater chance of a given port being

 

 

 

elected as the root port

 

 

 

 

 

 

Port Cost

A value used by STP to evaluate paths –

19-100Mbps Fast Ethernet ports

 

 

STP calculates path costs and selects the

4-1000Mbps Gigabit Ethernet ports

 

 

path with the minimum cost as the active

 

 

 

path

 

 

 

 

 

 

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)

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