Abstract: A cloud computing environment includes a key management server and a cloud computer system running several virtual machines. A virtual machine hosted by the cloud computer system includes an integrity check module for checking the integrity of the virtual machine and getting identity information of the virtual machine. The integrity check module sends a key request to a key management server, which provides key service to different cloud computer systems. The key management server validates the request and, if the request is valid, provides the key to the virtual machine. The key is used to unlock an encrypted file system in the virtual machine.

Abstract: There is described an electronic mail messaging system in which a plurality of user computers are connected to a mail registration server via the Internet. The mail registration server stores plural sets of decryption data, each set being required to decrypt a corresponding encrypted electronic mail message. Following receipt of an encrypted electronic mail message, a user computer communicates with the mailed registration server to effect decryption of the encrypted electronic mail message using the corresponding decryption data stored by the mail registration server. In this way, the accessing of the electronic mail message can be monitored by the mail registration server.

Abstract: There is described a computer network system in which a computer is in network communication with a server. In order to install a software package on the computer, installation software forming part of the software package is executed which requests entry of an email address for the user of the software package on the computer. The entered email address is then transmitted to the server, which in response sends an email to the email address including a Uniform Resource Locator (URL) addressing a local web server forming part of the software package, with installation information being appended to the URL. When the user of the computer accesses the URL using a web browser, the local web server automatically sends the installation information to the installation software. In this way, it is established that the user of the software package has access to the entered email address.

Abstract: There is described a computer network system in which a computer is in network communication with a server. In order to install a software package on the computer, installation software forming part of the software package is executed which requests entry of an email address for the user of the software package on the computer. The entered email address is then transmitted to the server, which in response sends an email to the email address including a Uniform Resource Locator (URL) addressing a local web server forming part of the software package, with installation information being appended to the URL. When the user of the computer accesses the URL using a web browser, the local web server automatically sends the installation information to the installation software. In this way, it is established that the user of the software package has access to the entered email address.