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Smart Meters Reveal What You're Watching

Unknown Lamer posted more than 3 years ago | from the we're-always-watching dept.

Privacy 170

xororand writes "H-Online reports that 'researchers at the Münster University of Applied Sciences have discovered that it is possible to use electricity usage data from smart electricity meters to determine which programmes consumers are watching on a standard TV set. By analysing electricity consumption patterns, it is, in principle, also possible to identify films played from a DVD or other source.' It's time for some clever EEs to come up with a countermeasure. Unfortunately alumfoil hats have already been dismissed."

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Hmmm... (2)

MightyMartian (840721) | more than 3 years ago | (#37459824)

I'm guessing if you built a plugin AC device that just sort of created random draws on your electrical supply, say ten times a minute, for random durations, I imagine that would pretty much kill any leak of such information.

Re:Hmmm... (0)

Anonymous Coward | more than 3 years ago | (#37459930)

I would bet you could defeat this by plugging in about 3 sets of those random-flashing cheap Chinese Christmas lights in a closet somewhere.

Re:Hmmm... (1)

tripleevenfall (1990004) | more than 3 years ago | (#37460656)

In China, Christmas lights watch YOU!

Re:Hmmm... (1)

Chatterton (228704) | more than 3 years ago | (#37459932)

It will kill any leak, but explode your electricity bill :-(

Re:Hmmm... (1)

vlm (69642) | more than 3 years ago | (#37460070)

No all you need to screw up their signature is "about equal to a TV".

Now insert the stereotypical /. complaint from coasties that they can easily afford a $1200K house on their $50K salary the only problem being the 15 cent per KWh draw of their 200 watt TV will surely bankrupt them. Happens every "electricity consumption" /. article. Close on the heels of the "The average american watches TV 8 hours per day, works 16 hours per day, sleeps 8 hours per day, and commutes in their vehicle at 5 MPH on the freeway for 4 hours per day loving every minute of it while hating electric cars, so this will bankrupt them" comment.

Re:Hmmm... (3, Informative)

MatthiasF (1853064) | more than 3 years ago | (#37459956)

You could also buy a cheap uninterruptable power supply (battery) or line filter (capacitors) for the same effect.

Unlikely the battery or filter would draw 1 for 1 from the wall and would probably smooth the signal out enough to be indistinguishable.

Re:Hmmm... (1)

PIBM (588930) | more than 3 years ago | (#37460004)

Actually, there`s always a non-neligible loss of power from the AC => DC => AC conversion :(

Re:Hmmm... (2)

MightyMartian (840721) | more than 3 years ago | (#37460012)

That's a good point. A UPS isn't a bad idea for your electronics, and can save you from nasty things like lightning strikes and overloads.

Re:Hmmm... (0)

Anonymous Coward | more than 3 years ago | (#37460370)

Get a continuous conversion UPS, then charge rate is independent of usage.

Re:Hmmm... (1)

dougmc (70836) | more than 3 years ago | (#37460414)

You could also buy a cheap uninterruptable power supply (battery) or line filter (capacitors) for the same effect.

A (cheap) UPS generally latches it's output directly to the A/C input rather than conditioning the power in any way beyond a surge protector. If there is a problem with the incoming power, it disconnects the A/C input and switches to battery in a fraction of a second, but until that happens, it wouldn't do much to mask exactly how much power is used from instant to instant (beyond the small amount of power it consumes itself, mostly to charge it's battery.)

Some fancier UPSs are always powered by the battery and these would have the desired effect, but they aren't the cheap ones you'll find at Frys.

Re:Hmmm... (1)

Muros (1167213) | more than 3 years ago | (#37460494)

You got there before me. Cheap UPSs have a mechanical switch. Inline UPSs are much more expensive.

Re:Hmmm... (1)

mrmeval (662166) | more than 3 years ago | (#37461440)

The line filtering and surge suppression in a UPS is active all the time but the batteries are not. A ferroresonant transformer will smooth out transitions in both directions; it is an always on device.

http://www.allaboutcircuits.com/vol_2/chpt_9/6.html [allaboutcircuits.com]

The transformer does smooth fast transients from either load or line but there is still variation. I've only used the ones for computers that have a clean sinewave out.

There are ones so noisy they'd swamp any line monitoring but using them for electronics is not a good idea.

Re:Hmmm... (1)

Artraze (600366) | more than 3 years ago | (#37460102)

You could just do it with a cron script or similar. I doubt the variance they're picking up is any larger than the difference between idle and full power on a modern desktop computer. Hell, just leaving a bunch of tabs open on Firefox while watching TV may provide enough variance to prevent this analysis.

Re:Hmmm... (1)

DarkOx (621550) | more than 3 years ago | (#37460236)

Probably not a cron script. If you introducing noise to obfuscate information that might leak through a side channel attack like this you want that noise to be as random as possible. If its predictable someone may be able to work out that pattern, interpolate what the side channel data would look like with out it, and then run their original analysis.

What would be better is a little C program that read a byte two from /dev/urandom, slept that number of ticks, woke up did some calculations on some more random values, and then went back to sleep for the length of the result. The more spiky the CPU utilization the better.

Re:Hmmm... (0)

logjon (1411219) | more than 3 years ago | (#37460480)

Cron + prng + switch would have a similar effect.

Re:Hmmm... (1)

Artraze (600366) | more than 3 years ago | (#37460504)

That's not really going to do it. This attack seems to rely primarily on the dynamic back lighting in modern LCDs. That and the line about "second by second" implies that the detection bandwidth is 1Hz, and more likely minute long detections of average light and dark periods which they then correlate to known values in the streams they're searching. As this is very low frequency, you'd want your noise band to be more like .001 - 1Hz rather than 10 to 1000 Hz as you are implying, where it would average out over the periods they're measuring.

That said, a C processes would still be the better choice; the cron bit was mostly a quip to highly the unnecessary extreme of building a discrete device.

P.S. Bonus points if you have your program just SIGSTOP/SIGCONT BOINC or similar :)

Re:Hmmm... (2)

fuzzyfuzzyfungus (1223518) | more than 3 years ago | (#37460198)

It might well be easier(and possibly even more efficient) to plug the object you don't want leaking data into a proper dual-conversion UPS, tweaked slightly to allow itself to discharge to a random level(somewhere between 50 and 90 percent, say) before starting a charge cycle.

Re:Hmmm... (1)

Reece400 (584378) | more than 3 years ago | (#37460202)

Two TV's on at the same time, on different channels?

Re:Hmmm... (1)

Thud457 (234763) | more than 3 years ago | (#37460498)

That's what I'd do if I had a million dollars.

Re:Hmmm... (1)

owlstead (636356) | more than 3 years ago | (#37460926)

You don't need a million dollars to own two TV's. Second hand TV's especially come pretty cheap (compared to many other costs anyway, not that that matters if you are broke...)

Re:Hmmm... (1)

amRadioHed (463061) | more than 3 years ago | (#37461144)

I'm pretty sure he was making an Office Space [youtube.com] reference.

Re:Hmmm... (1)

owlstead (636356) | more than 3 years ago | (#37460918)

And they would find out what you are displaying on two TV's, and the one that never zaps, or zaps in the middle of the movie, that's the one you are not watching.

Re:Hmmm... (1)

Trax3001BBS (2368736) | more than 3 years ago | (#37460300)

Very good.

Even being on the Internet while the TV is on, not that either are ever off or unused at my place.
----

If someone goes to the extreme of monitoring your electrical usage,
you best be growing pot or your in a world of hurt.

Re:Hmmm... (0)

Anonymous Coward | more than 3 years ago | (#37460306)

No, it wouldn't. It would just mask the signal a little (increase the noise). Unless the noise is much larger than the signal, it should still be possible to extract information about the non-random part of the signal.

Re:Hmmm... (1)

owlstead (636356) | more than 3 years ago | (#37460888)

And, knowing a bit about side channel attacks and statistics, you would be wrong.

Re:Hmmm... (0)

Anonymous Coward | more than 3 years ago | (#37461148)

I had some experience with Ethernet over Power Lines a few years ago. It worked OK, until someone turned on a vacuum cleaner or hair dryer. Just run a vacuum cleaner in another room.

the conter mesure is implied in the artcle (1)

JonySuede (1908576) | more than 3 years ago | (#37459834)

Light and dark passages in these films, large volumes of data, and a minimum of interference from other devices are the key to performing this analysis.

turn on a motor that draws at least 0.5A and you should be safe from those boxes....

I fail to see how it would work anyhow (2)

Sycraft-fu (314770) | more than 3 years ago | (#37460126)

They say that "a minimum of interference from other devices". Right, except my electricity meter is for my house, and it has many other devices. So unless you think I'm going to turn off all my lights, my computers, unplug my fridge, shut off my A/C, and so on when I watch a movie, then I can't see this working.

Also there's the fact that light vs dark really doesn't have much difference in terms of power draw on an LCD. Yes there is a bit used to change the crystals, but not nearly as much as the backlight. Then to that you add maybe a receiver, drawing power to do sound and so on.

I could see this perhaps working if you had a meter right on the feed to the TV, but on the whole house? Good luck getting useful data when the A/C is running, drawing 30 amps.

Re:I fail to see how it would work anyhow (0)

JonySuede (1908576) | more than 3 years ago | (#37460246)

the fridge have a motor of more the 1amp so does the A/C
computer switching power supplies are also a good source of line noise
therefore I agree with you, this have no chance of working in the field.

Re:I fail to see how it would work anyhow (1)

Artraze (600366) | more than 3 years ago | (#37460366)

Lights, Fridge, A/C don't provide much noise, and neither will an idling computer*. The last is largely because many people these days use laptops (low power with a big filter to begin with) and often leave them sleeping or with no apps running. Of course, if they're actually using it while watching TV, then all bets are off.

The thing about TV's, is what you said would be true for CRTs and early LCDs, but I think this will depend a lot on the dynamic features that LCDs employ. Very dark scenes diminish the back light, while very bright will turn it up. Flashing will cause the panel to basically overdrive crystals, etc. I can imagine that, with enough time, you can pick up useful power deviations.

*I'm assuming the variations they're picking up are on the order of 5W, which are easily distinguished from 100W cooling devices / stoves and the mW white noise that a light might provide.

Re:I fail to see how it would work anyhow (1)

JonySuede (1908576) | more than 3 years ago | (#37460724)

I disagree with you, I was in a lab in a past life, that use to develop software to detect things that I can't talk about but I can tell you without breaking my NDA that the fridge compressor was our worst enemy.

Re:I fail to see how it would work anyhow (1)

JonySuede (1908576) | more than 3 years ago | (#37460768)

Also I can tell you that the application was not for any three letters agencies neither was it for the police forces. I would not break anything by telling that it was a modified smart-meter from a European company. That as far as I can talk about it without getting sued...

Re:I fail to see how it would work anyhow (0)

Anonymous Coward | more than 3 years ago | (#37460394)

Simple... a refrigerator and air conditioner have fairly predictable power cycles based on time of day and local weather. Simply look for those patterns in the data and subtract it out. Having computers or other devices plugged in would add noise to the data. But if you fit the known data for various movies with the meter data I bet you could find a good enough correlation to know what you are watching.

Here is how you really defeat this: Press pause and rewind a lot.

But who knows, maybe you will accidentally create a pattern that correlates with a terrorist training video and have the DHS render you to a secret torture chamber for questioning.

Burn them (1, Interesting)

Anonymous Coward | more than 3 years ago | (#37459850)

More reason to ban their implementation!
Power companies should NEVER be allowed to gain knowledge about, nevermind make a profit from my porn viewing habits!

LOL Alumfoil (1)

stevegee58 (1179505) | more than 3 years ago | (#37459894)

Dang. Y'all'd think they had a differnt word fer everthang over thar.

Simple countermeasure (0)

Anonymous Coward | more than 3 years ago | (#37459904)

Turn on another TV and display a different channel or play a different DVD.
With all the possible combinations that presents good luck trying to determine what is being watched on either TV.

Re:Simple countermeasure (0)

Anonymous Coward | more than 3 years ago | (#37460540)

Or mooch power off of your neighbor. If they didn't want me to use their power, why did they run that power line right along the fence. Oh, they claim it is for the "pool filter" or some such. I believe it was for me to use.

Easy... (0)

Anonymous Coward | more than 3 years ago | (#37459906)

Batteries.

Van Eck Phreaking (0)

Anonymous Coward | more than 3 years ago | (#37459914)

What's even scarier is them being able to tell exactly what you are watching
http://en.wikipedia.org/wiki/Van_Eck_phreaking

Re:Van Eck Phreaking (1)

JonySuede (1908576) | more than 3 years ago | (#37460016)

According to page 6 of the referenced paper on Van_Eck_phreaking applied to lcd, it does not works on hdcp. A win for DRM, who would have thought.

Re:Van Eck Phreaking (1)

queazocotal (915608) | more than 3 years ago | (#37460666)

If you read carefully that - it says only if the HDCP signal goes all the way to the display. It doesn't.
Inside the monitor, the cable from the mainboard of the monitor to the LCD screen contains an unencrypted LVDS signal still, which can be snooped.

Re:Van Eck Phreaking (1)

JonySuede (1908576) | more than 3 years ago | (#37461000)

you are right, they could probably filter the hdcp signal and tune to the unencrypted LVDS.

Re:Van Eck Phreaking (0)

Anonymous Coward | more than 3 years ago | (#37460164)

A blast from the past, and PGP wasn't even mentioned this time.

Why do it like this when the cable box can report (1)

Joe_Dragon (2206452) | more than 3 years ago | (#37459918)

Why do it like this when the cable box can report a lot more info about what you are viewing and does not need new hardware to pull it off.

Re:Why do it like this when the cable box can repo (0)

Anonymous Coward | more than 3 years ago | (#37460074)

Because the electric company doesn't own the cable company. It wants its cut.

On a side note, I did interview for a cable box data mining company. Its a bit freaky what they send back and the information they can get out of it.

Re:Why do it like this when the cable box can repo (1)

Trax3001BBS (2368736) | more than 3 years ago | (#37460530)

I've never connected my DirecTV to a phone line or to the Internet because of this.

The set complains every so often :} and no I've never ordered any on demand program or PPV.

Re:Why do it like this when the cable box can repo (2)

LordKronos (470910) | more than 3 years ago | (#37460108)

Well, for starters, I'm assuming the cable company wouldn't want to be sharing its data with the electric company. Second, this is useful for anyone who doesn't have a cablebox. Cablecards installed into a TV, PC, or anything other than a cablebox are inherently one-way devices. The current spec has no mechanism for them to do 2-way communication (unless it's a SDV system that requires a tuning adapter). The same is true for the little DTA devices and QAM tuners.

Re:Why do it like this when the cable box can repo (2)

marnues (906739) | more than 3 years ago | (#37461214)

To add to the other commenter, cableboxes are mostly one-way devices as well. They keep trying to implement 2-way communications, but even if the box is capable the cable company I work for does not implement this. Video engineers are a dying breed because they don't want to learn about things like 2-way communication and packet switching. I can guarantee that once the network engineers have their way and video is just another packet service, the pipes will be cleaner, your digital feed will be much smoother, and Nielson will be dead as a doorknob.

BATTERY BACKUP (1)

schwit1 (797399) | more than 3 years ago | (#37459922)

And what if the TV, STB and various players are connected via a battery backup?

Re:BATTERY BACKUP (0)

Anonymous Coward | more than 3 years ago | (#37461094)

I had the same thought, power -> battery -> inverter. (or use a battery operated set with the charger on) Seems like kind of a waste though.

The key seems to be that it has to be a known program, they couldn't see the picture you're seeing, only identify its signature.

A *far* easier and more reliable way might be for them to simply ask the person what they're watching? :-)

Stupid (0)

Anonymous Coward | more than 3 years ago | (#37459944)

Okay, just think about it for a minute.

If you watch, using the same TV and cable box, the same show, of course that pattern is going to show up. However if you leave both on 24/7, there is much less to trace, but it gets better, the length of the show and the commercials also generate a signature. A LCD television doesn't really use that much power, but a CRT does, when it comes to brightness. However what's completely missed is audio, which 300 watts of power can be used in a full surround system if you're one of those audiophiles who like to play things till the walls shake. Solution? Headphones and dump the CRT's. For more privacy, use a DVR and timeshift everything.

Are you a pirate? Good news, the same rule applies.

At any rate just run other noisy stuff at the same time like defragment your hard drives while watching TV, that will mask out the Hard drive activity from watching or recording on the PVR.

A new DPA application (2)

Andy Dodd (701) | more than 3 years ago | (#37459946)

In the cryptography world, this is known as a sidechannel attack - specifically DPA.

"It's time for some clever EEs to come up with a countermeasure."
There are plenty of countermeasures for DPA in the crypto world - However:
1) The negative impact of this is a hell of a lot lower than key extraction
2) The positive effects of having power consumption tied to scene brightness are significant. Localized backlight dimming means that a scene with low average brightness uses less power. OLED displays take this to another level - black pixels use no power.

Also - In this case it appears they were only able to identify which channel a TV was tuned into. DVR makes this MUCH more difficult because fast-forward/rewind vastly increases the number of datasets you need to compare against. Also, while in theory you could identify a DVD, the selection of possible DVDs is so great and the amount of noise in the measurements is such that you're never in practice going to be able to identify someone's watched content reliably.

Re:A new DPA application (0)

Anonymous Coward | more than 3 years ago | (#37459980)

OLED displays take this to another level - black pixels use no power.

Wow, I can play Doom 3 without using any power at all... but then I'd be playing Doom 3.

Re:A new DPA application (0)

Anonymous Coward | more than 3 years ago | (#37460344)

Also - In this case it appears they were only able to identify which channel a TV was tuned into

That technology was developed in England in the 60s by Peter Wright (80s Spy Catcher controversial book chap, over being conned out of his pension) IIRC. It's ancient and was how they used to track down Russian spies making their transmissions.

Also the same tech BBC used to prove people had TVs when their vans were out putting the willies on people who didn't have a license. Although it's worth noting, no one ever saw such a van and was probably more about shitting people up knowing the whats_that_device_tuned_to tech, was rather long in the tooth by then. And I'm sure the BBC never "proved" anything with this.

Re:A new DPA application (1)

Andy Dodd (701) | more than 3 years ago | (#37460454)

No, it wasn't.

The technologies you're thinking of are:
1) Van Eck phreaking (affects CRTs) - not sure of any actual implementations of this that were of much use
2) Local oscillator leakage detection - many TV tuners use a standardized IF frequency, and you can analyze IF and LO leakage to determine where it's tuned. This is also how "radar detector detectors" work.
3) Generic radio direction finding - hunting down Russian spies that are transmitting is a lot easier than detecting a receive-only device.

This is a different technique - it analyzes the power usage patterns of a household and matches those to the expected power usage patterns that a set of candidate content would cause in order to determine which content choice was viewed. The larger this content set becomes and the smaller the time intervals compared become (e.g. arbitrary pauses/rewinds/fast-forwards for DVR recordings, Internet streaming, and DVD/BluRay viewing), the harder the task becomes.

Re:A new DPA application (0)

Anonymous Coward | more than 3 years ago | (#37460482)

Its not too bad to find things in large datasets. Use a hash...

Even if you have say 50 shows that are 'close hashes' you can at least get close... Getting close lets you narrow in...

Re:A new DPA application (0)

Anonymous Coward | more than 3 years ago | (#37460582)

You underestimate the scale of Google's set of server farms.

Re:A new DPA application (0)

Anonymous Coward | more than 3 years ago | (#37461096)

It is easy to just look at the light patterns coming out of the windows.

Even easier, look through a window.

Easiest, text your neighbor with "What are you watching?"

DVR's negate this (1)

gurps_npc (621217) | more than 3 years ago | (#37459976)

And most new cable boxes include a DVR.

Of course, the reason a DVR negates this is that they draw a huge amount of electricity even when you are not watching the show. They are the biggest single draw of electricity most people have. Incredibly wasteful, but so addictive.

That is because current versions always need to be "on" if you want to record something when you are not around to turn it on.

Supposedly, new versions will be able to go into 'sleep' mode until their internal clock says it is time to wake up.

Re:DVR's negate this (1)

geekoid (135745) | more than 3 years ago | (#37460082)

" biggest single draw of electricity most people have. "

citation needed. I would doubt it pulls more power then my electric stove. or furnace.

Re:DVR's negate this (1)

Tekfactory (937086) | more than 3 years ago | (#37460188)

It is on more often than your stove, and maybe more than your furnace. The article I read stated DVRs were a bigger drain than new energy efficient Fridges which used to be second only to AC as power draws.

I was feeling pretty bad about my 2 Tivo habit, so I googled it and apparently Tivo got some Energy Star rating not too long ago for power savings versus their previous models.

And to the detriment of the GP, a DVR with pretty much consistent power usage decrypting content and constant spinning hard drive would not negate this, the TV would still be the power spiking on the TV as scenes got darker and lighter. Now if the person watching your smart meter setup a hash of the movie or show you were watching, it might not adjust for commercial skipping.

Re:DVR's negate this (1)

vlm (69642) | more than 3 years ago | (#37460284)

" biggest single draw of electricity most people have. "

citation needed. I would doubt it pulls more power then my electric stove. or furnace.

I've seen those studies, and it is true if you live a nearly amish lifestyle w/ respect to other electronic devices. Perhaps in a small dorm room? If you exclude everything that can compete, what you want to win usually wins by virtue of being last standing. Also cherry pick the oldest, most wasteful DVR that has ever been deployed in at least quantity 1 to at least one home on the planet. I haven't been able to follow the money to figure out what they are trying to do, maybe they own patents on saving DVR power and are trying to sic the greenies on them to get them to buy patent licensing...

People like putting AV gear in closets / closed door boxes in their living room. Supposedly people watch TV for 8 hours a day or some nonsense, which means it reaches steady state temperatures every day. Think logically... if the DVR drew 1 KW, then the first day the owner watched TV it would set the "entertainment console" on fire. Therefore you can guess that it must draw less than, say, 100 watts, so as to remain below liquefaction temperature.

UPS (1)

Mister Whirly (964219) | more than 3 years ago | (#37459988)

And using a UPS should easily defeat this. Move along, nothing to see here.

In Soviet Amerika.. (1)

Roachie (2180772) | more than 3 years ago | (#37460014)

wait for it....

TV watch YOU!

Re:In Soviet Amerika.. (3, Funny)

prefec2 (875483) | more than 3 years ago | (#37460648)

I thought TV in America is like TV in 1984, but in color and with more channels.

In other news (1)

brusk (135896) | more than 3 years ago | (#37460028)

A similar effect can be achieved by analysis of photon leakage through amorphous silica, aka looking through your living room window.

Re:In other news (1)

Anonymous Coward | more than 3 years ago | (#37460190)

They do even better.

Hidden 3G Chips in TV sets without visible antennas. They run a long strip of metal inside the wafer and connect that to the chip all underneath the top layer..

Don't say I didn't warn you. The problem is they don't transmit until a receiver picks up a short wave broadcast. So until they are nearby or interested, your device emits no suspicious RF and no one finds anything.

Posting AC for obvious reasons.....

Re:In other news (0)

Anonymous Coward | more than 3 years ago | (#37460520)

Wouldn't the hundreds of hidden cameras in every room of your house be a much better option for seeing what you're seeing than integrating it directly into the TV?

How about... (2)

walkerp1 (523460) | more than 3 years ago | (#37460040)

simultaneously running an identical device with an inverted signal? Now may I please have my daily allotment of tinfoil? Yummy!

Actually, this is not too new. (0)

Anonymous Coward | more than 3 years ago | (#37460084)

Privacy matters re: smart meters is not a new topic. An interesting article [ieee.org] from last year on IEEE Spectrum discusses the same problem in relevance to using home appliances. Two researchers quoted provide a couple of ideas as counter-measures; batteries being one of the two.

Opps, the BS meter went off again (0)

frovingslosh (582462) | more than 3 years ago | (#37460118)

OK, I might believe this if one is using a Plasma Display or an old CRT TV (and I stress the "might"). But with a modern LCD display the lighting pretty much stays on and the LCD liquid crystals are turned on and off. The power to make the screen update changes is minimal and certainly can't be detected at the meter, so the claim from the article "Light and dark passages in these films ...." is simply not going to be valid for a modern TV. And if you're watching on an old CRT TV we already know that you're watching old re-runs of "I Love Lucy", so what's the point?

Re:modern LCD display (1)

DocSavage64109 (799754) | more than 3 years ago | (#37460448)

Plenty of modern LCD displays use dynamic back-lighting to improve contrast and low light detail.

From wikipedia [wikipedia.org] : "Since the total amount of light reaching the viewer is a combination of the backlighting and shuttering, modern sets can use "dynamic backlighting" to improve the contrast ratio and shadow detail. If a particular area of the screen is dark, a conventional set will have to set its shutters close to opaque to cut down the light. However, if the backlighting is reduced by half in that area, the shuttering can be reduced by half, and the number of available shuttering levels in the sub-pixels doubles."

Countermeasures (2)

StikyPad (445176) | more than 3 years ago | (#37460128)

Countermeasures already exist. They're called capacitors.

Don't use smart meters (0)

Anonymous Coward | more than 3 years ago | (#37460136)

How about just not using smart meters. Works for me.

The bigger problem is ... (1)

xkr (786629) | more than 3 years ago | (#37460146)

Anybody who can hack into the communications link (already published -- easy to crack) can tell if you are home or not. Ideal for someone wanting to break in. Also, a working husband can easily track a stay-at-home (maybe) wife's activity.

Re:The bigger problem is ... (0)

Anonymous Coward | more than 3 years ago | (#37460812)

That doesn't work. When I leave the house, I leave the TV on. And I keep it on ESPN to not only make it look like someone is at home, but is a male.

Why go to the trouble? (1)

jdcope (932508) | more than 3 years ago | (#37460148)

The feds can just ask the cable companies what you are watching. They'll cave.

Standard TV set (2)

vlm (69642) | more than 3 years ago | (#37460156)

I think the key in the article is "standard TV set" by which they mean a CRT. A CRT varies its HT current draw by scene brightness, and its quite visibly obvious when troubleshooting. Heck even a cheapie consumer grade wattmeter could probably detect it. On /. a CRT is probably not considered a "standard TV" anymore, but out in the real world, deployed CRTs on the ground showing shiney pictures probably still outnumber all other deployed and working technologies, at least for a few more years...

On the other hand, the florescent backlight in my piece of junk basement LCD TV is constant power draw, no matter if the LCD pixels let light thru or not. The LCD pixels themselves draw about the same no matter scene brightness. Anyone who's ever done anything with embedded systems knows this... the LCD display itself is usually rated around a milliamp, most of which is wasted in the control ckts, and the backlight usually draws a good fraction of an amp. Even allowing for much higher current draw for fast moving scenes and higher contrast, I'm betting the backlight still wins for power draw.

Re:Standard TV set (0)

Anonymous Coward | more than 3 years ago | (#37460376)

If they can see an opposite wall, the technology used to transmit the light is irrelevant. Late 80s or early 90s, we could work out what people had on their screens by the light reflecting from the walls. I would would imagine with today's tech, a reasonable picture would be viewable in realtime.

Re:Standard TV set (1)

owlstead (636356) | more than 3 years ago | (#37461092)

"I think the key in the article is "standard TV set" by which they mean a CRT. A CRT varies its HT current draw by scene brightness, and its quite visibly obvious when troubleshooting. Heck even a cheapie consumer grade wattmeter could probably detect it. On /. a CRT is probably not considered a "standard TV" anymore, but out in the real world, deployed CRTs on the ground showing shiney pictures probably still outnumber all other deployed and working technologies, at least for a few more years..."

Maybe in the third world, but in NL, you would really strugle to find a household that stills uses a CRT, let allone an electronics store, that still sells CRT's. I'm on my second LCD already, and I only buy when something breaks (ok, the remote broke, but a 17" wide screen without HDMI and FullHD is not much as main screen :).

I see CRT's regularly though - mostly in storage rooms in the house, because people keep stuff that works, and bringing the TV to the recycle center is a job in itself.

The technology is too expensive (0)

Anonymous Coward | more than 3 years ago | (#37460230)

Utilities don't want to pay for this capability to be in their meters. It's expensive both in terms of hardware and software. In an industry where every penny counts, utilities simply aren't going to demand this capability, and they really don't care what you're watching, anyway.

Get another TV (1)

cvtan (752695) | more than 3 years ago | (#37460264)

Have two TVs on at the same time viewing different programs.

Re:Get another TV (1)

vlm (69642) | more than 3 years ago | (#37460340)

Have two TVs on at the same time viewing different programs.

The crypto equivalent of xoring the same passphrase on two known plaintexts. Not gonna work.

Its like saying a fourier transform can detect two individual sine waves, but not a combination of sine waves. not how it works. In fact it's great at that.

After all these years (1)

Dunbal (464142) | more than 3 years ago | (#37460478)

They still don't get it. TV on != watching. I know a hell of a lot of people who just have it on to have background noise but are paying exactly zero attention to the television.

Re:After all these years (0)

Anonymous Coward | more than 3 years ago | (#37461278)

Yes, that's right - just like "caller ID" systems can't ID the caller, only the telephone number. This system can ID what channel a TV is tuned to, but not who's watching.

Re:After all these years (1)

AkkarAnadyr (164341) | more than 3 years ago | (#37461332)

Indeed. When we turned off cable in the nineties, an eager young fellow came to the door with a proposition. He was from Nielsen, and was delighted to find a family with a TV and no cable! We signed up for a year or so, and they came in with some incredibly frowzy phone lines and dongles to automate sending data summaries at 3AM.

We drove them bonkers with long periods of watching Channel 68, which was static/snow in our area without a registered channel. They kept calling to ask to check on the health of the system, and we had to keep telling them the data was accurate - we had it on for white noise so the baby could sleep while we did housework.

Finally we bailed just to get them to shut up, since dealing with this special case seemed to be beyond their comprehension, let alone their data gathering protocol.

"Try and understand the words, they will be English: 'We don't watch TV.' "

Told them that up front, yet they still wanted our info. Except not really. Sayonara, suckers.

UPS? (0)

Anonymous Coward | more than 3 years ago | (#37460500)

Plug in multiple devices to a UPS so the output seen at the smart meter is a merged signal from the UPS and when you throw in the voltage smoothing and battery charging of the UPS I doubt whether you could use this technique. A power strip with multiple devices drawing from it would probably do the trick as well.

Re:UPS? (1)

wisnoskij (1206448) | more than 3 years ago | (#37460798)

Well unless I am mistaken the smart meter does not know what outlet you are plunged into, as the breaker is the only thing that knows that and that is normally inside and owned by the building owner.

And multiple things running at the same time for the most part is useless as everyone always has multiple things running at the same time. the basic idea here is that most things have a ~ constant voltage while a TV varies a lot and it is the change in voltage that matters and corresponds to a particular show.
And yes you have lights turning on a off, heaters and coolers doing the same, ovens heating up and then just maintain temp but thoes are all big jumps that last for at least minutes, TVs very at every frame.

Any other var load on the circuit would counteract (1)

guruevi (827432) | more than 3 years ago | (#37460558)

It is indeed possible if you have a constant or recurring draw from other sinks (like resistive lights, capacitive motors etc.) but I guess if you have even one of those malfunctioning with a random draw (such as an off-center aquarium pump or an AC unit) or you add signals (like X10 or Ethernet-over-Powerline) that this kind of 'attack' is quickly trumped unless you can get right at the circuit where the TV is on. For that matter, I think an optical attack would be much more reliable (where you measure the light output reflection through someone's windows as they watch TV) but then you might just be find that a spy cam and/or a telelens is much more reliable. If you have those CableCo DVR boxes, they can also be queried remotely.

What else you could do with a smart meter (2)

prefec2 (875483) | more than 3 years ago | (#37460598)

See when you open your refrigerator, when your heating kicks in even if it is gas driven due to the start pulse. Every electricity consumption can be monitored and it can be interpreted allowing to see when you get up, what your behavior is (at home). That's why we need data security. No company should be allowed to use these data other than to control electricity production.

Re:What else you could do with a smart meter (0)

Anonymous Coward | more than 3 years ago | (#37461038)

No company should be allowed to use these data other than to control electricity production.

There is the biggest misunderstanding of smart meters. Smart meters have NOTHING to do with electricity production. Smart meters are about minimizing production and maximizing revenue. Smart meters are smart for utilities and companies like Cisco that make the meters themselves. For the consumer they are another drain on the wallet.

What's the biggest selling point the utilities use when pushing smart meters and tiered billing? The push "savings". You can use electricity when the rates are lower. But the reality is that there is no savings.

How this would actually work, and its real limits. (2)

queazocotal (915608) | more than 3 years ago | (#37460618)

This is not as simple as some people think to block. A simple random load added to the mains signal will not do it.
In order to find out if you're watching a given TV program - first you take the TV program, and measure every 5 second periods average brightness..
This gives you 720 samples for an hour.
Now, you load up 720 5 second samples from the targets electricity meter.

You subtract the average value from each of these, so they're symmetrical about 0.

Now, you go through the list, multiplying the first brightness by the first measured energy use, and add this to a total. Repeat this 720 times.

Now, you have the correlation of the power with the TV program.
This is _MUCH_LARGER_ than the correlation of any single time period, and any noise or random non-correlated signal such as fridges or freezers drops out to a large degree.

Random signals have to be of the order of sqrt(720) - 36 times larger than the signal to mask it.

(It's not quite this bad, as there will be some false correlation, epecially given there will be millions of candidate programs, and 5s offsets that can occur)
And yes, LCDs, especially LCDs with newer variable power 'energy saving' backlights that dim or brighten along with the program content to optimise contrast and power use will work for this just fine.

I make these Smart Metering Devices (1)

Anonymous Coward | more than 3 years ago | (#37460682)

First you are not going to get second by second readings from your standard L&G or Itron meter. The back haul doesn't have the bandwidth and even if you had a second broadband ESI (energy service interface) in your home there are a few technical hurdles preventing 1 second granularity (2.5 seconds is the fastest that I've seen and not sustained).

However these meters also report the phase difference between the Voltage and the Current. Using this information you can filter out pool pumps, air conditioners, furnace fan etc. As you learn more about what is on in a persons home it does become easier to figure out how an individual appliance is working.

There are a large number of privacy concerns that need to be addressed with Smart Metering. We should probably solve them before some companies start using your personal electricity consumption as a revenue stream

Re:I make these Smart Metering Devices (2)

xororand (860319) | more than 3 years ago | (#37460844)

First you are not going to get second by second readings from your standard L&G or Itron meter. The back haul doesn't have the bandwidth and even if you had a second broadband ESI (energy service interface) in your home there are a few technical hurdles preventing 1 second granularity (2.5 seconds is the fastest that I've seen and not sustained).

However these meters also report the phase difference between the Voltage and the Current. Using this information you can filter out pool pumps, air conditioners, furnace fan etc. As you learn more about what is on in a persons home it does become easier to figure out how an individual appliance is working.

There are a large number of privacy concerns that need to be addressed with Smart Metering. We should probably solve them before some companies start using your personal electricity consumption as a revenue stream

Thanks for the info, AC.
I wish I had mod points.

Useless research (1)

Ossifer (703813) | more than 3 years ago | (#37460748)

FTFA: "Light and dark passages in these films, large volumes of data, and a minimum of interference from other devices are the key to performing this analysis."

My smartmeter reports hourly total usage, not "large volumes of data"...

Re:Useless research (0)

Anonymous Coward | more than 3 years ago | (#37460956)

The research is very useful. It's your reading comprehension that is lacking.

Respectfully,
The NSA

Re:Useless research (0)

Anonymous Coward | more than 3 years ago | (#37461270)

My smartmeter reports hourly total usage, not "large volumes of data"...

That's just what they want you to think.. What wee need to defeat these "smart meter" monitoring devices is a massive flywheel energy storage system to flatten out your energy usage pattern.. Our computer controlled flywheel system will calculate your average energy usage and feed or draw power from the flywheel as needed to maintain a constant power draw from the grid..

You'll just be a flat line to them..

Finally! (1, Funny)

srussia (884021) | more than 3 years ago | (#37461032)

I can camouflage my grow op simply by modulating the lights using a photocell aimed at a TV tuned 24/7 to Fox News!

Re:Finally! (0)

Anonymous Coward | more than 3 years ago | (#37461134)

What could possibly go wrong with Fox News-mutated THC?

so what? (0)

Anonymous Coward | more than 3 years ago | (#37461376)

if someone wants to monitor my electricity usage to figure out i am watching something on tv my only complaint would be that they are wasting my money doing it. I'm not going to make it worse by trying to hide something from them, let them be bored... on directtv couldn't they just query my box anyway if they really wanted? to do this in bulk on whole communities, what could they possibly be hoping to figure out? to do it for an individual there must be better ways, a simple wireless bug comes to mind. it sounds like a cute intellectual exercise by someone who has never heard of how spies could figure out what was being typed on electric typewriters, or could directly pick up video signals remotely, or bounce a laser beam off a window to listen to voices, etc, etc, etc.

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