title: The Oxford Common File Layout
creators: Andrew Hankinson David Wilcox Simeon Warner
abstract: The Oxford Common File Layout (OCFL) initiative is an effort to define a shared approach to file hierarchy for long-term preservation. What began as a discussion at the Fedora and Samvera Camp held in Oxford, UK in September of 2017 has grown into a focused community effort. Many repository systems store large amounts of data that are difficult to migrate, and such migrations risk data loss. Within a storage system, digital objects should be designed under the assumption that they will be accessed and managed by a variety of applications. This effort is an attempt to decouple the structure of the persisted files from the software that might manage it by creating an expectation of file hierarchy to which software applications must conform, whether implemented in a conventional filesystem with files and directories, or in an object store. Thus the file hierarchy functions as a storage Application Programming Interface (API). This effort addresses three primary requirements: 1) completeness, so that a repository can be rebuilt from the files, 2) parsability, both by humans and machines in the absence of original software, and 3) robustness against errors, corruption and migration between storage technologies. This paper describes motivations, principles and anticipated features of the proposed file layout. The OCFL initiative aims to produce draft specifications for trial use by Fall 2018.
keywords: boston