Neurotronics began work on OpenXDF in 2003 with the goal of providing a modern, open, and extensible file format with which clinicians and researchers can share physiological data and metadata, such as signal data, signal montages, patient demographics, and event logs.
[citation needed] Neurotronics released the first draft of the OpenXDF Specification just before the 18th meeting of the Associated Professional Sleep Societies in 2004.
OpenXDF is a tiered framework designed to allow standardized and custom specializations of the format while enforcing a common foundation that provides a high-level of compatibility between unrelated systems.
OpenXDF supports encryption of the XML file using TwoFish in Cipher Feedback (CFB) mode with a 256-bit key created from a UTF-8 encoded password hashed with SHA-256.
In addition, OpenXDF supports integrity verification using a SHA-512 hash of the original XML file.