Tresorit

Introduction 

The quantity of companies providing the service of file storage has grown to the number 10, however, there still remains the issue of the unreliability of these servers. The idea of such service is of course brilliant, but the hackers are pretty brilliant at breeching the fragile walls of any virtual storage room. The problem has stayed on the developers' agenda till 2011, when the Hungarians led by Istvan Lam founded Tresorit. This is the one and only server using AES-256 and HMAC codes for SHA-512.

Features 

To raise the authority of the server and prove it capable of top security for its users' confidential information, the administration of the company organized a contest for hackers in 2013. An award in the amount of $10,000 would have been given to the hacker who could infiltrate the server. Well, the codes remain intact today and the server works according to the principal of Dropbox, that is you enter it through the user's program and paste your files which are then synchronized with the cloud storage room. 

Bottom Line 

If you are often in urgent need of different files and a cloud server is the only option for the amount you need to store and operate daily, then Tresorit is the best server you can find.