hi Shiby Way 2 is the only way to prevent the Client from decrypting data, but if you go that far that the user will debug your client he´ll be able to intercept the data after generating and before sending. This is a securityhole you can´t close. If the data you want to send gets larger you should go a middle-way between 1 and 2, because with asymetric encryption you can only encrypt small blocks. (e.g. with rsa 2048 bit you can encrypt 245 byte which will result in 256 encrypted byte). Encrypting with a asymetric algorithm is also slower than a symetric one. The middleway would be then: encrypt everything with a randomly generated symetric key and encrypt only this key asymetric for passing it to the server. Azraelgod

Hi! I`m tryng to connect to a ftp-server which allows only a secure connection. Connecting with Flashfpx it works with both "auth ssl" and "auth tls", but when i try to do it with the menatils security-library and the example ftp-client i get this exception: 220 (glFTPd 2.00 Linux+TLS) ready. AUTH TLS 234 AUTH TLS successful Org.Mentalis.Security.SecurityException: An error occurs while communicating with the remote host. ---> Org.Mentalis.Security.Ssl.Shared.SslException: The server hello message uses a protocol that was not recognized. at Org.Mentalis.Security.Ssl.Shared.CompatibilityLayer.ProcessServerHello(Byte[] bytes, Int32 offset, Int32 size) in D:\ssh-server\seclib-1.0\seclib\Security\Ssl\Shared\CompatibilityLayer.cs:line 80 at Org.Mentalis.Security.Ssl.Shared.CompatibilityLayer.ProcessHello(Byte[] bytes, Int32 offset, Int32 size) in D:\ssh-server\seclib-1.0\seclib\Security\Ssl\Shared\CompatibilityLayer.cs:line 71 at Org.Mentalis.Security.Ssl.Shared.SocketController.OnReceive(IAsyncResult ar) in D:\ssh-server\seclib-1.0\seclib\Security\Ssl\Shared\SocketController.cs:line 82 --- End of inner exception stack trace --- at Org.Mentalis.Security.Ssl.SecureSocket.EndSend(IAsyncResult asyncResult) in d:\ssh-server\seclib-1.0\seclib\security\ssl\securesocket.cs:line 380 at Org.Mentalis.Security.Ssl.SecureSocket.Send(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags) in d:\ssh-server\seclib-1.0\seclib\security\ssl\securesocket.cs:line 326 at FtpClient.SendCommand(String command) in d:\csharpproggies\windowsapplication1\ftpclient.cs:line 146 at FtpClient.DownloadFile(Url url, Int32 choice) in d:\csharpproggies\windowsapplication1\ftpclient.cs:line 115 at FtpClient.Start() in d:\csharpproggies\windowsapplication1\ftpclient.cs:line 91 at FtpClient.Main(String[] args) in d:\csharpproggies\windowsapplication1\ftpclient.cs:line 48 I´ve read somewhere that the menatlis-library didn´t support dhe/dss and the server seems to need this. Here´s a part of the log when connecting with FlashFXP: [R] AUTH SSL [R] 234 AUTH SSL successful [R] Connected. Negotiating SSL session.. [R] SSL negotiation successful... [R] SSL encrypted session using cipher DHE-DSS-AES256-SHA (256 bits) [R] PBSZ 0 [R] 200 PBSZ 0 successful I´ve been told OpenSSL would support this authenticationmode, but i don´t have a clue how to use this library in my project. Any suggestions and help will be appreciated. Azrael