Chapter 17 Spanning Tree Protocol

 

Table 29 STP Status (continued)

 

LABEL

DESCRIPTION

 

Hello Time

This is the time interval (in seconds) at which the root switch transmits

 

 

a configuration message. The root bridge determines Hello Time, Max

 

 

Age and Forwarding Delay.

 

 

 

 

Forward Delay

This is the time (in seconds) the root switch will wait before changing

 

 

states.

 

 

 

 

Current Bridge Status

 

 

 

 

MAC Address

This is the MAC address of the current bridge.

 

 

 

 

Priority

Priority is used in determining the root switch, root port and designated

 

 

port. The switch with the highest priority (lowest numeric value)

 

 

becomes the STP root switch. If all switches have the same priority, the

 

 

switch with the lowest MAC address will then become the root switch.

 

 

Priority determines the root bridge, which in turn determines the Root

 

 

Hello Time, Root Maximum Age and Root Forwarding Delay.

 

 

 

 

Max Age

This is the maximum time (in seconds) the Switch can wait without

 

 

receiving a BPDU before attempting to reconfigure. All Switch ports

 

 

(except for designated ports) should receive BPDUs at regular intervals.

 

 

Any port that ages out STP information (provided in the last BPDU)

 

 

becomes the designated port for the attached LAN. If it is a root port, a

 

 

new root port is selected from among the Switch ports attached to the

 

 

network.

 

 

 

 

Hello Time

This is the time interval in seconds between BPDU (Bridge Protocol Data

 

 

Units) configuration message generations by the root switch.

 

 

 

 

Forward Delay

This is the maximum time (in seconds) the Switch will wait before

 

 

changing states. This delay is required because every switch must

 

 

receive information about topology changes before it starts to forward

 

 

frames. In addition, each port needs time to listen for conflicting

 

 

information that would make it return to a blocking state; otherwise,

 

 

temporary data loops might result.

 

 

 

 

Path Cost

Path cost is the cost of transmitting a frame on to a LAN through that

 

 

port. It is recommended to assign this value according to the speed of

 

 

the bridge. The slower the media, the higher the cost.

 

 

 

 

Root Port

This is the number of the port on the Switch through which this Switch

 

 

must communicate with the root of the Spanning Tree.

 

 

 

 

Refresh

Click this to update the status screen.

 

 

 

 

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GS1510 Series User’s Guide