Abstract: A cloud storage system supporting user agnostic encryption and deduplication of encrypted files is described. Further the cloud storage system enables users to share a file, a group of files, or an entire file system with other users without a user sending each file to the other users. The cloud storage system further allows a client device to minimize the utilization of bandwidth by determining whether the encrypted data to transfer is already present in the cloud storage system. Further the cloud storage system comprises mechanisms for a client device to inform the cloud storage system of which data is likely to be required in the future so that the cloud storage system can make that data available with less latency one the client device requests the data.

Abstract: A method and apparatus for securing a directed acyclic graph (DAG) is described. In one embodiment, an algorithm enables encryption of a DAG given a start node (an entrypoint), the node key for that node, and a path to traverse in the graph. A unique and cryptographically random key is generated for each node (sometimes referred herein as a unique node key). The node key encrypts the node it is generated for and also any edges exiting the node. The node key is stored on the incoming edge to the node (the edge from its parent node) encrypted with the node key of the parent node. Storing the keys on the edges of the DAG instead of on nodes of the DAG enables efficient querying of the DAG and the ability for a node to have multiple parents that may change without affecting the node's relationship with the non-changing parents.

Abstract: A cloud storage system supporting user agnostic encryption and deduplication of encrypted files is described. Further the cloud storage system enables users to share a file, a group of files, or an entire file system with other users without a user sending each file to the other users. The cloud storage system further allows a client device to minimize the utilization of bandwidth by determining whether the encrypted data to transfer is already present in the cloud storage system. Further the cloud storage system comprises mechanisms for a client device to inform the cloud storage system of which data is likely to be required in the future so that the cloud storage system can make that data available with less latency one the client device requests the data.