Comments on: Security Review: Traffic Lights http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/ Sat, 17 May 2008 07:32:37 +0000 http://wordpress.org/?v=2.5.1 By: Michael Loftis http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-5288 Michael Loftis Tue, 22 Apr 2008 10:04:10 +0000 http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-5288 Traffic lights commonly include an independent sort of fail-safe circuit called an "opposing green" detector. If this circuit (sometimes it's mechanical) sees greens go on that would cause opposing traffic to be directed at eachother, it will short the system to some form of flashing red or red/yellow or flashing yellow until the DOT gets out to the box to examine the fault. Traffic lights commonly include an independent sort of fail-safe circuit called an “opposing green” detector. If this circuit (sometimes it’s mechanical) sees greens go on that would cause opposing traffic to be directed at eachother, it will short the system to some form of flashing red or red/yellow or flashing yellow until the DOT gets out to the box to examine the fault.

]]> By: sam http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4993 sam Fri, 11 Apr 2008 18:19:59 +0000 http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4993 Um... surely you simply make the emergency vehicle signal set the traffic lights to all red. Since the emergency vehicle is allowed to cross to the other side of the road and go through the red. Something that would be safe when all the lights are red so no other traffic is moving... That way it's useless to people who want to give themselves and green light. Um…

surely you simply make the emergency vehicle signal set the traffic lights to all red. Since the emergency vehicle is allowed to cross to the other side of the road and go through the red. Something that would be safe when all the lights are red so no other traffic is moving…

That way it’s useless to people who want to give themselves and green light.

]]> By: James Youngman http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4475 James Youngman Wed, 26 Mar 2008 00:44:21 +0000 http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4475 Plurals don't have apostrophes. You might also want to watch the 1969 film, "The Italian Job", for a related example. Plurals don’t have apostrophes. You might also want to watch the 1969 film, “The Italian Job”, for a related example.

]]> By: Jon Thompson http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4299 Jon Thompson Fri, 21 Mar 2008 15:57:09 +0000 http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4299 It would be really simple to stop spoofing for the most part. Assign a randomized serial number to each preemption device, and have that device send the serial number. The reader then compares with a known-good/known-bad database and either allows the user through properly or notifies the police. If further protection is needed, you can use some sort of active encryption between the devices. It would be really simple to stop spoofing for the most part. Assign a randomized serial number to each preemption device, and have that device send the serial number. The reader then compares with a known-good/known-bad database and either allows the user through properly or notifies the police. If further protection is needed, you can use some sort of active encryption between the devices.

]]> By: Rene Schickbauer http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4270 Rene Schickbauer Fri, 21 Mar 2008 11:34:29 +0000 http://cubist.cs.washington.edu/Security/2008/02/03/security-review-traffic-lights/#comment-4270 Traffic lights are (most of the time here in europe) controlled by a PLC (Programmable Logic Controller), located in a grey box near the crossing. The box usually looks like one of those used by phone companies to patch lines. Modern traffic lights (and similar equipment) in the US starts to use standardized hardware and communications protocols, see also <a href="http://en.wikipedia.org/wiki/Traffic_lights#Controller_system" rel="nofollow">Wikipedia</a> and <a href="http://www.ntcip.org/" rel="nofollow">NTCIP.org</a>. This, of course, should give any attacker all information required, as well as possible access to "evaluation equipment" when posing as a possible buyer or security tester. Traffic lights are (most of the time here in europe) controlled by a PLC (Programmable Logic Controller), located in a grey box near the crossing. The box usually looks like one of those used by phone companies to patch lines.

Modern traffic lights (and similar equipment) in the US starts to use standardized hardware and communications protocols, see also Wikipedia and NTCIP.org.

This, of course, should give any attacker all information required, as well as possible access to “evaluation equipment” when posing as a possible buyer or security tester.

]]>