But the displays don't give away too much.
Highlighting technology used to keep sensitive information safe
from prying eyes and ears, the displays range from a Teletype "hot line" with turn-of-the-century encryption technology to devices still being developed that use computers to scan physical characteristics such as facial features and fingerprints.
"This is an exhibit that I didn't think would be shown while I was still working," said Jack E. Ingram, the museum's curator and historian who has worked for NSA for more than 30 years. "It was highly classified just a few years ago. NSA doesn't keep secrets just for secret's sake, and when we can tell stories, we are."
But the agency is still keeping some things under wraps.
For example, the display of devices used by U.S. troops from the Vietnam War to the present to disguise radio communications uses only the outer coverings of the devices, according to Larry Roelofs, a senior electronic engineer with NSA who helped assemble the exhibit. All the components have been removed from inside the metal containers, which are displayed in glass and wood cases.
And while Roelofs is happy to explain how an NSA-designed plastic bag will show evidence of tampering once the seal pattern has been broken, he won't reveal how a floppy-disk pouch made of yellowish transparent plastic is resistant to tampering.
"There are other techniques that aren't public," he said.
The exhibit, which opened last week, goes beyond the museum's focus on the history of making and breaking codes and takes visitors into the field of protecting information as it is transmitted via airwaves, telephones, computers and satellites.
The exhibit includes a Norwegian-made Teletype encryption device used in the Washington-Moscow hot line, which allowed U.S. and Soviet heads of state to communicate securely from 1963 to the early 1980s.
Each country had to use identical encryption tape to exchange messages. Any person who wanted to intercept the messages would have to have the same tape the machines were using.
"It came about in 1918 and it still can't be broken today," Roelofs said.
The exhibit also traces the evolution of telephones used for secure conversations between government officials.
The first devices, used only by U.S. diplomats, were filing-cabinet-sized units worth $35,000 each in the 1960s with voice quality "similar to listening to Donald Duck," according to Roelofs. Today, the $1,500 units are the size of typical electronic office telephones, and can be found in many government offices where workers use plastic keys containing computer-chips to switch the telephones from normal to secure communications.
Only one display in the exhibit lets visitors get a taste of biometrics, the technology that uses computers to identify people by their physical characteristics, such as facial features and fingerprints. Visitors can have their thumbprints scanned and displayed on a screen inside a case.
Although the exhibit hardly gives away secrets, Ingram and Roelofs hope it will make the public more aware of the risks to security breaches and NSA's role in preserving national security, a role that was barely known even to the families of NSA employees until recent years.
Pub Date: 12/24/96