TP-Link TL-SG3424P manual Application Example for STP Function, TC Protect

Port:	Displays the port number of the switch.
Loop Protect:	Loop Protect is to prevent the loops in the network brought by
	recalculating STP because of link failures and network congestions.
Root Protect:	Root Protect is to prevent wrong network topology change caused by
	the role change of the current legal root bridge.
TC Protect:	TC Protect is to prevent the decrease of the performance and stability
	of the switch brought by continuously removing MAC address entries
	upon receiving TC-BPDUs in the STP network.
BPDU Protect:	BPDU Protect is to prevent the edge port from being attacked by
	maliciously created BPDUs
BPDU Filter:	BPDU Filter is to prevent BPDUs flood in the STP network.
LAG:	Displays the LAG number which the port belongs to.

7.4.2 TC Protect

When TC Protect is enabled for the port on Port Protect page, the TC threshold and TC protect cycle need to be configured on this page.

Choose the menu Spanning Tree → STP Security → TC Protect to load the following page.

Figure 7-11 TC Protect

The following entries are displayed on this screen:

TC Protect

TC Threshold: Enter a number from 1 to 100. It is the maximum number of the

TC-BPDUs received by the switch in a TC Protect Cycle. The default value is 20.

TC Protect Cycle: Enter a value from 1 to 10 to specify the TC Protect Cycle. The default value is 5.

7.5 Application Example for STP Function

Network Requirements

Switch A, B, C, D and E all support MSTP function.

A is the central switch.

B and C are switches in the convergence layer. D, E and F are switches in the access layer.

There are 6 VLANs labeled as VLAN101-VLAN106 in the network.

All switches run MSTP and belong to the same MST region.

The data in VLAN101, 103 and 105 are transmitted in the STP with B as the root bridge. The data in VLAN102, 104 and 106 are transmitted in the STP with C as the root bridge.

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