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STP provides one direct route for packets of information. This eliminates the loops that happen when other routes are available.
The objective of this document is to explain how to setup the global STP (Spanning Tree Protocol) settings. This configuration covers both the Global and Bridge settings.
Steps to Configure Global STP
Step 1. Log in to the web configuration utility and choose Spanning Tree > Global STP. This opens the Global STP page.
Step 2. In the Spanning Tree State drop-down list, choose the appropriate option.
• Disable — This disables STP for the device.
• Enable — This enables STP for the device.
Step 3. In the STP Operation Mode drop-down list, choose the appropriate option. This indicates the STP mode.
• Classic STP — This is a network protocol used to eliminate loops. This is the default value.
• Rapid STP — This is just like Classic STP but at a faster speed.
• Multiple STP — This includes all spanning tree information but in a single BPDU (Bridge Protocol Data Unit) format.
Step 4. In the BPDU Handling drop-down list, choose the appropriate option. BPDUs are used to transmit spanning tree information.
• Flooding — This option sends the packet information to all ports. This is the default option.
• Filtering — This option sends the packet information to ports that need the information instead of sending it to all the ports.
Step 5. In the Past Cost Default Values drop-down list, choose the appropriate option.
• Long — This option specifies a 0 to 200,000,000 range for port path costs.
• Short — This option specifies a 0 to 65,535 range for port path costs. This is the default option.
Step 6. In the Priority field, enter a value for the bridge priority. Each switch/bridge is assigned a priority when it runs STP. The default value is 32,768. The range is 0 to 65,535, but in increments of 4,096. The lowest value provides the greatest priority.
Step 7. Click the appropriate radio button option.
• Hello Time — This sends messages through the most preferred path with the least hop counts. This indicates the grace period, the time that is spent between messages being sent. If this is selected, a value in seconds will need to be entered into the field to the right. The default value is 2 seconds. The range is 1 to 10 seconds.
• Max Age — This indicates the time that the device waits to send a message through any available path. If this is selected, a value in seconds will need to be entered into the field to the right. The default value is 20 seconds. The range is 6 to 40 seconds.
• Forward Delay — This indicates the time that a message is held on the path before it completes the message transfer. If this is selected, a value in seconds will need to be entered into the field to the right. The default value is 15 seconds. The range is 4 to 30 seconds.
Step 8. Click the Save Settings button.