From American Forces Press Service:
Many intelligence analysts and historians contend the SIGABA cipher device is one of the most important encryption systems the U.S. military has ever known.
Wednesday, it was also a time machine.
The unusual contraption first brought two young cryptologists together during World War II, and nearly 60 years later it has reunited them, sparking memories of their critical work.
The National Security Agency’s National Cryptologic Museum in Fort Meade, Md., recognized Helen Nibouar and Marion Johnson during a ribbon cutting ceremony unveiling a new exhibit entitled, “60 Years of Cryptologic Excellence.”
“We not only break codes, but we make codes ... and we stand on the shoulders of giants,” NSA Deputy Director Chris Inglis said of Nibouar and Johnson. “When we celebrate Marion and Helen’s return to the scene of their early work, we’re actually celebrating a long legacy of the history of the National Security Agency.”
As the United States stepped up its search to fill non-combat positions in support of World War II, Nibouar and Johnson initially interviewed for typist-clerk positions. On the day of her interview in the Signal Corps building, Nibouar, while at a water fountain, met a woman who encouraged her to give cryptology a try.
She did, but confessed to having no prior familiarity with the field. Johnson said she took a similar path to cryptology, although she was more outspoken during her interview.
“The [hiring officials] asked me if I liked to do crossword puzzles and I said, ‘No, I hate them!’” Johnson said. “But they hired me anyway.”
Nibouar trained at Morrison Field in West Palm Beach, Fla., where she met Johnson, and the two became fast friends, with no idea they were forging their place in history by obscuring troop movements and other classified material.
“What was really, really difficult was all the messages came in five random letter groups separated by spaces,” Nibouar said. And though she typed about 100 words per minute, putting code to tape was considerably more painstaking.
“You couldn’t type very fast because you couldn’t make a mistake or it would mess up the message,” Nibouar said.
After Florida, Nibouar’s cryptology journey took her to California, Hawaii and even Japan. And though Johnson worked in different locations, the women wrote letters to keep in touch.
All the while, a shrouded, arduous work life and extended time apart from family became the norm for the two women. A single message could take hours to process. They often received messages so secret that even they were excluded from seeing them.
“The first thing the message would say is ‘eyes only,’ and we had to stop, not hit another key, get up and go somewhere,” Nibouar said. “And an officer in charge came and decoded the message, taking it by hand straight to Gen. [Douglas] MacArthur.”
When asked what she thought the messages might have said, Nibouar quipped, “It might have been to have a party.”
Transition back into normal life couldn’t come too soon for the women, they said.
“I just wanted to go home and get married,” Johnson said.
Nibouar also wed, had three children, became a teacher and spent a great deal of time volunteering -- which, at age 91, she continues to this day.
She marvels at modern intelligence technology, but describes SIGABA developer Frank Rowlett as a genius for the machine’s simple design and complex capabilities.
National Cryptologic Museum Curator Patrick Weadon said the SIGABA derives from an earlier randomizing system, Enigma, developed by the Germans.
During World War II, people frequently used electro-mechanical devices to communicate securely, Weadon said.
“Enigma was thought to be utterly secure by the Germans because it produced permutations and possibilities of 3x10114 which made it theoretically impossible to crack,” he said.
But the Allies did crack Enigma -- as early as 1940 -- prompting the Signals Intelligence Service to develop SIGABA, Weadon said.
SIGABA designers looked at the shortcomings and the frailties of Enigma and designed a machine that had the power of Enigma without its shortcomings, Weadon said.
SIGABA’s distinctive ability to advance rotors with another set of rotors made it impenetrable, Weadon explained.
“It was never cracked, it was a perfect machine from the moment it was put on line and it was perfect the day that they took it off,” he said. “You’re talking about a perfect encryption machine, which many people even today believe is practically impossible [to crack],” he added.
Weadon said he’s sure the courage and bravery of U.S. and Allied troops won the war, but the ability to communicate securely on a more consistent basis than the Axis powers ultimately cinched victory.
“When you’re reading the other guys traffic and they can’t read yours -- you got ‘em,” he said.