Process to access a data storage device of a cloud computer system

A computer system comprising:

• a gateway computer system and a cloud computer system, the gateway computer system being connected with the cloud computer system over an external network, the gateway computer system configured to store authentication data of registered users for authentication with respect to the cloud computer system and at least one cryptographic key for each registered user, a registered user being associated with a first asymmetric cryptographic key pair, the first asymmetric key pair including a first public key and a first private key, the cloud computer system configured to store a file directory for files stored in a data storage device of the cloud computer system, and the gateway computer system further configured to store a replica of the file directory, and
• the computer system is configured to,
• set up a protected connection between a first piece of terminal equipment of one of the registered users and the gateway computer system over the external network;
• transfer a DNS request over the external network from the first piece of terminal equipment to a DNS server, the DNS request including a request to retrieve an IP address of the cloud computer system based on a URL corresponding to the cloud computer system;
• receive a response to the DNS request, the response including an IP address of the gateway computer system instead of the IP address of the cloud computer system, from the DNS server by the first piece of terminal equipment;
• transfer a file to be stored on the cloud computer system over the protected connection from the first piece of terminal equipment to the gateway computer system, the file being unencrypted;
• set up a session over the external network between the gateway computer system and the cloud computer system;
• authenticate the registered user with respect to the cloud computer system by the gateway computer system accessing, through the session, the authentication data of the registered user stored in the gateway computer system, for authentication of the registered user;
• encrypt the file by the gateway computer system using the at least one cryptographic key;
• encrypt the at least one cryptographic key using the first public key of the first asymmetric cryptographic key pair associated with the registered user to produce a first ciphertext;
• transfer the encrypted file along with the first ciphertext through the session from the gateway computer system to the cloud computer system;
• store the encrypted file and the first ciphertext in a data storage device of the cloud computer system;
• produce a web page for displaying the replica of the file directory using the gateway computer system;
• transfer the web page from the gateway computer system to the first piece of terminal equipment over the protected connection;
• display the web page by the first piece of terminal equipment and inputting a selection for a file path in the displayed replica of the file directory for storage of the file;
• transfer the selection of the file path over the protected connection from the first piece of terminal equipment to the gateway computer system;
• transfer a storage command from the gateway computer system to the cloud computer system to store the encrypted file in the data storage device in accordance with the selection for the file path;
• receive an acknowledgment signal from the cloud computer system by the gateway computer system, the acknowledgment signal indicating successful execution of the storage command;
• and
• update the replica of the file directory after receipt of the acknowledgment signal of the storage of the encrypted file in the data storage device of the cloud computer system.