DTKA, a Prototype Implementation of Delay-Tolerant Security Key Distribution(NPO-49413-1)

Unlike all Internet mechanisms for security distribution (e.g., certificate authorities), DTKA operates over the extremely long signal propagation times and interrupted links that characterize communication with interplanetary spacecraft. It has no single point of failure and cannot be "spoofed" by an attacker's subversion of any single key authority machine (or even two key authority machines, in most configurations.