RFC 2773:Encryption using KEA and SKIPJACK
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file transfer


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... The File Transfer Protocol (FTP) provides no protocol security except ...
... user authentication password which is transmitted in the clear. In addition, the protocol does not protect the file transfer session beyond the original authentication phase ...


... Postel, J. and J. Reynolds, "File Transfer Protocol", STD 9, RFC 959std9, October 1985. ...



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