The 'secure' TETRA communications system has been used by police and security services for decades, it's been revealed that it's seriously flawed. Dr Tim Muller explains. #tetraburst #security #securitybreach The team that reverse engineered TETRA and discovered the problems: This video was filmed and edited by Sean Riley. Computer Science at the University of Nottingham: Computerphile is a sister project to Brady Haran's Numberphile. More at