Following the hack in Dallas, Milwaukee County determined its sirens were vulnerable to a similar type of tampering.
To date, no one has attempted to hack the 57 sirens in Milwaukee County.
But Monday, the county finished up the installation of encryption technology meant to keep the sirens protected against cybersecurity threats.
Roughly half of the 57 sirens are owned by the county. The other half are owned by local municipalities.
However, the county controls the activation of all the sirens from its 911 Center Downtown. It spent $47,000 to upgrade all of the sirens across Milwaukee County, including the ones owned by local governments.
The signals sent from the 911 Center to the sirens across the area will now be encrypted. They were previously unencrypted.
Erik Viel, Radio Services Director for the Office of Emergency Management, said it’s the same federal encryption standard used by the CIA and FBI.
“There’s a key that scrambles all the information that’s sent over the airwaves,” Viel said. “Then an encryption card at each siren decrypts it and executes whatever command we sent over.”