closed port

If you provided a wrong sequence of knocks ( or no knocks at all), you would receive a "Connection timed out" message, and the SSH port would remain completely closed with no sign of its existence.

如果提供了错误的敲门序列（或根本没有敲门），会收到Connection timed out消息，SSH端口仍然完全关闭，看不出它是存在的。

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The New York Port Authority said it had closed all bridges and tunnels into the city.

纽约交通部门权威人士称所有入城桥梁和隧道均已关闭.

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Note: Open Port pressure must exceed closed port pressure.

注意: 开户端口的压力必须超过关闭端口的压力.

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The normal-closed electromagnetic valve has reasonable structure design and good close property ofthe valve port to prevent leakage completely.

它结构设计合理，阀口关闭性良好，确保无任何泄漏。

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