The first port contacts the server on port 21, but instead of then issuing a PORT command and allowing the server to connect back to its data port, the client will issue the PASV command.

第一个端口连接服务器的21端口，与主动FTP模式中提交PORT命令并允许服务器来回连它的数据端口不同，客户端会提交PASV命令。

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There will of course be a new binding, a new service and a new port, as shown in Figure 21, Figure 22, and Figure 23 respectively.

当然将会分别使用一个新绑定、一个新服务和一个新端口，如 图 21、 图 22 和 图 23 所示。

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Suraev and Expedition 22commander Jeffrey Williams were the first to use the new docking portwhen they relocated their Soyuz TMA-16 spacecraft from the aft port ofthe Zvezda Service Module on Jan. 21.

苏雷耶夫和远征22的指挥官杰弗雷·威廉姆斯是首先使用新对接口的人，1月21日他们将联盟TMA-16飞船从星辰号服务舱尾部接口移泊于此。

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For instance, Web browsers generally bring HTML code into the system via port 80, while FTP programs transfer files through port 21.

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