Configuring Spanning Tree Spanning Tree
Configuration Guide  
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TC Protect
TC Protect function is used to prevent the switch from frequently removing MAC address 
entries. It is recommended to enable this function on the ports of non-root switches.
A switch removes MAC address entries upon receiving TC-BPDUs (the packets used to 
announce changes in the network topology). If a user maliciously sends a large number of 
TC-BPDUs to a switch in a short period, the switch will be busy with removing MAC address 
entries, which may decrease the performance and stability of the network. 
With TC protect function enabled, if the number of the received TC-BPDUs exceeds the 
maximum number you set in the TC threshold, the switch will not remove MAC address 
entries in the TC protect cycle.