Abstract: Techniques are presented for versioning file systems. Files and directories are versioned in a manner that permits the versions to be mounted on a device of a user. The original security restrictions that existed with the versions when they were versioned are retained with the mount. Moreover, the user can browse and access the versions via the mount using an existing file system of the user's device. Further, names for each of the versions include detailed information that reveals the relationship of each particular version to its parent version.

Abstract: Techniques are presented for snapshotting. Blocks associated with a storage volume are frozen from volatile access upon receipt of a snapshot request. Continued volatile access to the frozen blocks is permitted by transparently mapping each frozen block to an available block within the volume that is not associated with the snapshot. Volatile access continues on the available blocks.

Abstract: Techniques are presented for retaining security restrictions with file versioning. Files are versioned in such a manner that metadata including full directory paths and access restrictions are retained for each version of the file and enforced when each version is accessed. The files are versioned to hashed subdirectories for space and management efficiencies. In an embodiment, prior versions of a particular file are maintained as delta data structures while a most-recent version of that file is maintained in its full or complete data state.

Abstract: Apparatus, systems, and methods may operate to taking a snapshot of an origin volume in conjunction with a backup process in response to receiving a snapshot request by a snapshot service. A persistent time stamp associated with the creation time of the snapshot may be recorded on the origin volume. The persistent time stamp is accessible to the file system process associated with the origin volume in most embodiments. If access to a file is requested, the time the file was last modified may be compared with the persistent time stamp, and if the file modified time is earlier than the persistent time stamp, the file's archive bit can be reset. Otherwise, the archive bit is not reset. Additional apparatus, systems, and methods are disclosed.

Abstract: Techniques are presented for randomly generating bits. A seed is inverted and a non repeating portion of the resulting digits from the inversion are retained. The inverted seed is then raised to a power to acquire another non repeating portion or additional digits. This process is repeated for a desired number of iterations. The resulting digits are then selectively combined to generate a stream of randomly generated bits with an infinite period.

Abstract: Techniques for assuring a receiver's non repudiation of a communication are provided via cooperation with a secure device. A secure device operates within a local environment of a receiver and exchanges certificates with a sender via the receiver. The sender encrypts data in a communication with the receiver. Separately, the sender sends an encrypted version of a decryption key to the receiver. The receiver presents the encrypted version of the key to the secure device and the secure device supplies the decryption key for use by the receiver to decrypt the previously sent encrypted data.

Abstract: Techniques for assuring a receiver's non repudiation of a communication are provided. A sender encrypts data pursuant to a key. The encrypted data is sent to a receiver. A key to decrypt the data is sent separately to the receiver. The sender ensures the proper verifying information is acquired from the receiver for both the encrypted data and for the key.