The system is designed and implemented around the "Principle of Least Authority" (POLA). Strict adherence to this convention is enabled by the use of cryptographic capabilities which grant the minimal set of privileges necessary to accomplish a given task to requesting agents. A RAIN array acts as storage—these servers do not need to be trusted for confidentiality or integrity of the stored data.
Lee, Changhoon. Secure and trust computing, data management and applications : STA 2011 workshops: IWCS 2011 and STAVE 2011, Loutraki, Greece, June 28 - 30, 2011. Berlin: Springer. pp. 192–193. ISBN3642223648.