I have do investigate some ways and technologies to implement a server or client-server similar to dropbox (a simple repository)...
Probably I'm not making the best search but I can't find the best technologies to implement or some examples or open source projects that implement the file transfer part...
If you implement something like dropbox what technologies would you use?
Other question is, where is the best place to store all files?
Tks for your help and sorry for my english!
On
Regarding transport - the best bet is either WebDAV/S or SFTP as one of options (SSH supports username/password and custom login schemes). There's no need to invent anything custom.
Files should be stored on the disk (there were plenty of discussions here on SO regarding where and how to store files on such servers) or, if you plan to use cloud services (eg. Azure or Google App Engine) as a backend, in BLOB storage.
In general your question is overly broad - more precise and narrow questions would bring more specific and detailed answers.
For a simple way to have remote "places" where files can be placed and shared, and that can also be mounted as a network share, check the WebDAV protocol.