Learn about the atDirectory behind the atPlatform
atDirectories are the only centralized part of the atProtocol and are centralized to provide a single namespace and a global dependable platform. No data beyond the atSign and responding authoritative atServer is held on the atDirecory. This information is considered public and no authentication is required to look up the atServers for a particular atSign.
The atDirectory have been designed to scale to billions of atSigns and handle the request for atSign lookups at near real-time, globally. To achieve this, in-memory databases are utilized and only the absolute minimum of data is stored.