Multimedia

This may be out of thread , but are there facilities in the .NET framework
to address a situation like this ?

If there are video files being stored in .avi format , and if these have to
be encrypted , along with the corresponding audio files, and saved, and
subsequently be made available on demand, to authorized users over the
internet, are there any features in .NET / Windows which will allow me to :-

1) encrypt the .avi files and save it in a server,
2) read this encrypted file over the internet and decrypt it at the client
end to display it to authorized users,
3) prevent caching of this stream at the client end for better security,
4) allow the client to freeze, rewind frames , fast forward and have a video
like control over the stream ?

If there are issues here, would it help if the .avi files were converted to
Flash files ?

Regards.