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Aussie Speed Cameras in Doubt Because of MD5
An anonymous reader writes "A speeding case has been thrown out in Australia after the Roads and Traffic Authority admitted that it could not prove the integrity of speed-camera photos. 'The case revolved around the integrity of a mathematical MD5 algorithm published on each picture and used as a security measure to prove pictures have not been doctored after they have been taken.'" I wonder if Australian police are as (radar gun) trigger happy as they are in certain parts of the U.S.
and you don't get caught...
That sounds like a loophole. However I am not in favor of automated law enforcement, I like to face my accuser.
Many of those red light tickets were dismissed in the US for various reasons, some technical, some through loopholes, and some through plain old dishonesty in the ticket system operator. They had lowered the yellow light timing below legal standards to make more money. Outrageous if you ask me.
Law enforcement is supposed to be run by government employees, who have no axe to grind and nothing to gain by dishonesty. I like it like that.
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I've experianced speed cameras in both Queensland and Victoria and I have to say that by far Melbourne is the dodgiest of the lot. They claim that the cameras are there to save lives however they are little more then revenue raisers.
Melbournians are subjected to hidden cameras looking over overtaking lanes. The cameras are privatised so people get paid more the more cars they catch. The situation there is terrible.
Queensland is somewhat better because police are required to have a sign out saying that there are speed cameras in use, however this sign is usually conveniently placed behind a bush or behind the car with the camera in it. Queensland is also better off because the police do not rely so heavily on the revenue that their cameras drum up, it seems at times the only thing paying for Melbournes police is speeding offiences.
One thing is certain, these cameras do not save any lives. I remember clearly once in high school a Policeman came to give a talk on vehicle safety he showed us a big graph with a stedily declining death rate over the years, he pointed out the huge drop after the introduction of seat bealts, then one after they banned drink driving, and a smaller drop after the introduction of airbags. My hand immediently shot up and I asked him when speed cameras were introduced, my teachers just laughed and he never answered the question.
I think that is the point of the article. They take the picture, write it and a MD5 hash, then try saying that it is official because it has a matching MD5 hash. I can make any picture with a matching MD5 hash. Even this post can have a matching MD5 hash, does the MD5 hash prove that I wrote it?
Video Production Support
Dude! If are going to be going through a school zone with kiddies about (marked 40k's) at 45k's OVER THE LIMIT, (ie 85k's) then you well deserve to loose your licence for 12 months and cough up $451 bucks. I think you are getting off lightly.
Zilch.
I have a pysics teacher (also in WA) that drives as fast as he wants. Then when he goes to court for the speeding tickets he dazzles the judge with science and calculus until the ticket gets dropped.
Well then, if "as fast as he wants" means "much faster than the law allows", then I hope physics brings him some swift justice before he kills some innocent person who is not a complete ass.
War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
I wonder if Australian police are as (radar gun) trigger happy as they are in certain parts of the U.S.
Yes.
And I'd rather have a fine and a few points on my license than a murder conviction for running over a pedestrian at 90km/h in a 60km/h zone
If the laws being enforced are themselves unreasonable, a warning is not out of order. Just because something is "the law" does not mean it's reasonable or prudent.
"Why would a state voluntarily legislate to limit its power?"
Supposedly, the power comes from the people. It's not that the state would take it's power away, rather, it would be that the people have not yet conceeded that authority to it in the first place (by voting for, or electing people who vote for laws granting the state that power).
Let's assume this is the protocol:
- camera takes snap shot, uses signing key on tamper-resistant chip inside camera to sign a hash of that photo (with the time, speed, etc. concatenated onto the end of the photo before hashing)
- send bill to speeder (possibly including hash of picture or in some way "committing" to that particular md5sum)
Then, the problem the bad guy has is to find another picture with that same hash value. This is a preimage attack [find another photo that outputs this hash value] and the weaknesses in MD5 were collision weaknesses: particular collisions found and an algorithm for generating collisions. But collisions are just two messages that have the same hash value, not a particular hash value of your choosing.If the protocol doesn't have a way to securely associate a hash with a photo (e.g. doesn't sign it), then it doesn't make a difference if you're using MD5 or SHA-1 or SHA-256, the cops can still just doctor photos at will and only produce the hashes of the doctored photos. So this line of "attack" has nothing to do with underlying cryptographic weaknesses.
[Note also that the weaknesses in MD5 don't affect the security of HMAC-MD5]. Hell, the case should be thrown out since the defense atty had the temerity to issue this stunning (even in buzz-word-addled tech) mischaracterization: http://www.smh.com.au/news/national/motorist-wins
The point is not that you can generate multiple messages with the same hash; the point is that you can take a photo, doctor it, and plaster a new hash over the old one.
WARNING! Police in Washington enforce laws... that generate a revenue stream!
Personally I have no problem with Police enforcing laws, it's just when they go for the easy, (relatively) harmless, money-grabbing ones to the detriment of rapes, murders, assault, criminal damage, etc. that I have a problem.
Yeah, the problem is pretty bad where I live, too. Cops whoring themselves out for speeding fines when more serious crimes go reported and with no police response for hours or days.
F*** them.
Until he/she has a tyre blowout, or comes across an unexpected pothole in the road, or has to swerve to avoid a rabbit running across the road... at which point that extra 30mph or 50kmph could make a huge difference to the ensuing damage to the person and other people, not to mention their car. Those are things that can happen to anyone, no matter how good a driver they are.
Until he/she has a tyre blowout, or comes across an unexpected pothole in the road, or has to swerve to avoid a rabbit running across the road... at which point that extra 30mph or 50kmph could make a huge difference to the ensuing damage to the person and other people, not to mention their car. Those are things that can happen to anyone, no matter how good a driver they are.
Yes, that reminds me of something I witnessed about 25 years ago when I was a child. On a freeway a car flew past us at high speed, minutes later we drove past to see it, upside down, with a front type blown open and bloody bodies on the ground around it. I'll never forget that.
The World is full of people who are "better than average" in their own minds. Especially young people who think they are the next F1 champion. A while ago on TV in Australia, a current affairs type program got a bunch of hoons together to do a high performance driver training and testing. They all failed because they ALL went out too hard with something to prove. The funniest thing, was that the old guy training them, drove their own hotted up cars around the course much better and faster than the owners did.
War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
Yes, but on a four lane highway, where the most severe turn is about 30 degrees per mile, which is the 'unsafe speed'?
55(1980's speedlimit)
65(1990's)
75(current)
The road has been all of the above. Is 85 even that much of a stretch for a stable, well maintained car with good tires?
I've driven a number of vehicles, and there are a number that I wouldn't drive past 55-65 in on any road. It could be an immaculate runway and I wouldn't go that fast. On the other hand, I've driven a few sports-cars, and they feel more in control even going 30mph faster than the delivery truck.
I don't read AC A human right
Why anybody would swerve and risk their own life and the lives of others to avoid hitting a rabbit, squirrel, cat, et al is beyond rational comprehension.
Ignorance is curable, stupid is forever.
dude, if you're measuring your fuel consumption in litres per mile, you need a new car...
I measure mine in miles per litre...
(cluestick for mods: HUMOUR)
And the people shall be oppressed, every one by another, and every one by his neighbour Isaiah 3:5
Disclaimer I rarely watch "current affairs" on the commercial channels as I think most of it is crap. But I did see part of the story you mentioned...
"These hoons were humiliated. The point of the show was a challenge to the hoons to prove that they were good enough drivers to speed. They all failed."
Dead on, but even after all that some of them still could not see a problem with thier own speeding. They were male and had the "indestructable" attitude (I suffered the same syndrome 25 yrs ago and have the scars to prove it).
Off course we have vast highways over here where you can see a Camel 2km up the road, no traffic, no cops, no bends. Speeding is not a problem in the middle of nowhere, falling asleep and road-trains will kill you.
Speed limits are made so that the AVERAGE driver can make a stupid mistake once in a while and live to be honked at and humiliated. If EVERY driver is driving near thier skill limit then NOBODY can make a mistake, ever!
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
What about a child? Where would YOU draw the line?
That's a ridiculous question - dogs, cats, etc. are legally property. People are not. Of course I'd feel badly running over a cat or other cuddly animal, but if it's between that and losing control of the vehicle, causing perhaps thousands of dollars in damage or worse, injuring someone, the cat doesn't get a second thought at the moment. Certainly I avoid animals on the road where possible. However, the most important part of driving is judgement, and that means knowing when you just have to suck it up and barrel over someone's pet in the road for the greater good.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
Yes, but on a four lane highway, where the most severe turn is about 30 degrees per mile, which is the 'unsafe speed'?
The answer is: any speed other than the one all the other vehicles are moving at.
Numerous studies have shown that the most important factor in reducing the total number of accidents on highways is to get all of the vehicles moving at about the same speed. Driving the speed limit when everyone else is going 10 over is dangerous. Driving 10mph faster than everyone else is dangerous.
Higher absolute speed increases the severity of injuries in case of an accident, different roadways also impose a natural maximum (though the US Interstates were mostly designed for 80mph traffic, since the speed limit was 70mph when they were constructed), and weather conditions can change things dramatically, but the most important consideration in minimizing accidents is getting all of the cars moving at close to the same speed.
If you're the granny with cars whizzing by to the left and right, you're a hazard, even if you're going the speed limit. If you're the punk passing everyone and weaving through traffic, you're a hazard, even if your car is perfectly capable of handling the speed on that road. In both cases, it doesn't even matter how good of a driver you may or may not be... if your actions may surprise another driver, then you'll eventually cause an accident.
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