1.阻塞狀態

Discards frames received on the port（不收資料幀）

Does not learn addresses（不學習MAC地址）

Receives BPDUs（接收BPDU）

2. Listening State

Discards frames received on the port（不收資料幀）

Does not learn addresses（不學習MAC地址）

Receives BPDUs（接收BPDU）

3. Learning State

Discards frames received on the port（不收資料幀）

Learns addresses（學習MAC地址）

Receives BPDUs （接收BPDU）

4. Forwarding State

Learns addresses（學習MAC地址）

Receives BPDUs（接收BPDU）

5. Disabled State

Discards frames received on the port（不收資料幀）

Does not learn addresses（不學習MAC地址）

Does not receive BPDUs（不接收BPDU）