Ust?d variation with respect -to-office hours found in .nostlarge hwdqwirteps, afforded a lar~o neasurc.of concealment fs Snail volwo h. the- - of operational traffic. The practice of handling classified traffic in clear- text form over local land.linecircuits led to several security beaches, This mode of operation was extremely difficult to po- lice, and it was amazing that the number of violations was not greater. It was of dubious advantage during this operation except in delivering classified traffic between the Joint Crypto Center and the Air Force headquarters on ENIWETOK Island. This could have been accomplished with little delay by notor nessenger. Very little message traffic was passed between the various tributary communica- tion centers other: than information copies of messages to other points; these could in most cases be handled by mail. The small. number requiring off-line encryption would not have presented a significant workload. In view of these factors, the advantages of the transmission of classified matter in the clear over landlines are minor and are insignificant compared to the kzards involved. It should be noted that the hazards are not due to any threat of intercept, but to the possibility of compromise through operator error in the relay center. This raethodof operation definitely falls under the classification of a llpracticedangerous to security”. i. The JTF SEVEN Communication Center in the headquarters building on PARRY Island was operated without major problems other than organizational and personnel. Fron these viewpoints, much : 83