Over the Air Rekeying

Significance

These encryption keys usually comprised printed sheets, punched paper strips or cards, or electromagnetic tapes. The security of their production, transport, storage, distribution, accounting, employment, and finally destruction required thousands of trusted agents, world-wide. Vulnerability of so many physical keys to theft or loss became a statistical reality that was exploited for two decades by the infamous "Johnny Walker" spy ring. Elimination of this vulnerability through adoption of Over The Air Rekeying (OTAR) although little appreciated at the time, was an innovation of inestimable impact. Placing this technology in perspective, OTAR comprised a transformation at the most basic foundations of communications security such that through the decades since introduction of OTAR, not a single new breach of US code systems has occurred. Introduction of OTAR technology into practical application precipitated NSA creation of the Electronic Key Management System (EKMS) which permanently altered the power balance in communications security and espionage. Recent declassification of the details relating to its introduction may be expected to now become the subject of more scholarly work.