Embodiments of the present invention are directed to Web-Services-based data
backup and data-archiving applications that provide remote data
backup and data archiving to private individuals, small businesses, and other organizations that need reliable, secure, geographically remote, and cost-effective data
backup, data archiving, and backed-up and archived-
data retrieval. In one embodiment of the present invention, a private or small-business
client contracts with a
service provider for data-backup and data-archiving services. The
service provider, in turn, contracts with a remote data-storage facility to provide secure, reliable data backup and data archiving to the personal or small-business
client. A
client-side application is downloaded to the client computer and configured to allow the client to store locally encrypted data at the remote, data-storage facilities. Neither the
service provider nor the data-storage facility can decrypt or otherwise access the information stored by the client. In addition, the
encryption key or
encryption keys used by the client to encrypt the data for remote storage are securely stored at the remote, data-storage facility for subsequent
recovery by the client, should the client suffer damage or loss to a local computer
system. However, the client
encryption key is stored in a doubly encrypted fashion, preventing access to the client's encryption key by either the service provider or the data-storage facility. Certain embodiments of the present invention also provide local indexing for remotely stored, encrypted data and efficient storage of updates to already remotely stored data.