<html><head></head><body><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div>On May 17, 2018, John Gilmore < gnu at toad.com> wrote:</div><br>> Do the cops' radios have backdoors built in to them?<br><br>The articles I skimmed were pretty lowbrow and did not seem aware of this aspect. Schneier mentions it in his blog<br><br>https://www.schneier.com/blog/archives/2018/05/virginia_beach_.html<br><div><br>and one commenter says:</div><div><div><br><div>"TETRA systems for public safety and security agencies (PSSA) are almost always encrypted using TEA2 (Europe) and TEA3 (elsewhere). However the networks have recording systems which hold some or all call sessions for periods often exceeding 3 months. These recordings can be archived for longer periods if there is some question about the activities during the recorded period."<br><div><br><div>One assumes that such systems detect deletions, etc.<br><div><br><div><br><div>Mike<br></div></div></div></div></div></div></div></div><br><br><br><br><br><br></div></body></html>