It's not always practical for the President of the United States to go back to Air Force One to have private conversations without fear of eavesdropping. So the White House sets up a high-tech tent that permits him/her to talk with others securely. Such temporary structures are called Sensitive Compartmented Information Facilities or SCIFs:
This can mean creating a self sufficient pod with its own air supply, says Phil Lago, who is one of the founders of Command Consulting Group, a company which provides SCIFs to government agencies.
"We have to make sure that any kind of emissions don't get out. That could be from your laptop, your radio, your telephone," he explains.
Rather than a ring of steel around a secure complex, he likens it to a "ring of electronic waves" which prevents signals from getting in and out of the tent. The only signal which can get out is the encrypted communications, which are made through a secure and encrypted phone line, which sends conversations through a satellite, he says.[...]
The tent itself is windowless and is made from a secret material which is designed to keep emissions in and listening devices out.
Only those specially authorised can go inside a SCIF, with entry usually requiring a combination of pin numbers, access badges and biometric data.
The perimeters of the tent might be controlled by guards, but there would also be people monitoring outside to see if any data gets out. "You have a line of defence for everything," says Mr Lago.
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