I am looking for the shortest comprehensive way to explain to people that are trying to use DRM as a technology to prevent users from using their data in some fashion deemed undesirable, why their solution cannot work by definition.

Ideally I'd like something that:

  • Covers why technically it is impossible to have people access local data, but only in such-and-such a way
  • Imparts an understanding of why this is, to avoid follow-on "But what if" rebuttals
  • Is intuitive enough and short enough that even a politician (j/k) could grasp it

When faced with this situation I try to be clear and concise, but I usually end up failing at least on one of these points. I'd really like to have a 'stock' answer that I can use in the future.

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    I'm not sured your premise isn't slightly flawed. I don't believe that there's anything which makes DRM unworkable BY DEFINITION - even if there were technology has frequently advanced in such a way that the previously unworkable becomes trivial. Personally I'd argue from a practical point of view - that argument is (a) more compelling and (b) more easily understood. – Jon Hopkins Jul 28 '09 at 8:39

23 Answers 23


The fundamental problem with DRM is that you're giving somebody a locked box and the key used to open it. You're distributing a copy of the key with the lock. Every person that possesses a protected Blu-Ray, DVD, software package, and protected CD also possesses the key that will unprotect it.

The people who design the DRM systems can try as they might to hide the key such that only those in the know (i.e. authorized decryptors/players/users) can find it, but there are a lot of curious people in the world, and all it takes is one person (or group of people) to be smarter than the ones who hid the key, and the box is open forever. As soon as one unprotected copy of the content exists it can be distributed everywhere, making the protection on the other copies irrelevant.

  • This might work on more tech-savvy people, but still, not everyone (especially those that need convincing most) is going to grasp why the 'lock/key' analogy matches what DRM is ... also, I had hoped for something shorter... but this is a good start. – jerryjvl Jul 28 '09 at 6:00
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    AFAIK the decryption keys are NOT on the disc, but in the player - which means that DRM can work (technically) if and only if the player cannot be compromised, which is impossible to prevent if you want to have software players running on an open platform like a PC. – Michael Borgwardt Jul 28 '09 at 9:27
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    Frankly it's pretty much impossible even if all you have a hardware players. Since you can't control what the end users do with them, you can only make it more difficult to extract the key, never impossible. – Michael Kohne Jul 28 '09 at 18:21
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    lock+key in the same box; it's that simple. For those with the desire, unlocking is a given. DRM also invites piracy and prevents fair use. – Steven A. Lowe Jul 29 '09 at 0:13
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    @harrymc: Internet validation doesn't really help. As long as the product can be activated once, the activation process can be duplicated on an identical copy of the product. The product won't have any way to know if it's actually an internet it's connecting to, or a faked duplicate activation. (Besides, in practice you won't even have to go that far, just poke around and make a crack that always validates the internet activation part...) – Ilari Kajaste Sep 20 '09 at 19:32

Digital files cannot be made uncopyable, any more than water can be made not wet.

Bruce Schneier (source)

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    This is the crux of it for me. Not only will digital files always be copyable, but with the advent of the internet and the sharing of knowledge and applications which make the techniques required available to even the least tech savvy person, they will always be EASILY copyable. – Jon Hopkins Jul 28 '09 at 8:33
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    The point of people who believe in DRM, will be that copying the locked file doesn't matter at all. – Arjan Jul 28 '09 at 10:19
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    While this is a neat quote, it doesn't really EXPLAIN anything. – James McMahon Jul 28 '09 at 14:25
  • If I was allowed a sig on SO, I'd pick that. – Phil Lello Apr 30 '11 at 0:23
  • Considering how much emphasis the question put on making the explanation irrefutable, it's amazing that an answer so completely devoid of information got this many upvotes – Michael Mrozek Jun 28 '13 at 17:48

To sum the anti-DRM argument up in one easy word?


How could a game with such intrusive DRM restrictions not be able to stop its excessive piracy rate.

If you wanted the hypothetical politician to understand why DRM wont work, don't give them a tech talk, give them a shining example of where it went wrong. One key point that 'management types' need to understand is that a pirated copy (DRM bypassed) is not equivalent to a lost sale. It just so happens that people are prepared to pay good money for products when they see the value in those products. "Copy protection actually increases rather than decreases the piracy of games." What left wing nut job said that?? It was only Gabe Newell from Valve. Ignorant companies are now competing with their own product, they now have to compete with 'free'.

When software is cracked (generally within the first day of release), DRM then only hurts the loyal consumers who paid for the product.

Side comment: A good quote I found on the Internet regarding gaming piracy and steam.

I'm not pro Steam/Valve, I'm just anti-stupid.

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    Yes, from my personal experience the best way to explain something to the non-tech is by finding some analogue that this person is familiar with, or better yet by giving a live example. KISS principle. Use techy details and jargon only if you wish to intimidate him ;) – Kirill Strizhak Jul 28 '09 at 8:51
  • Arguably, the less 'tech' the answer is, the more universally understood it will be, so I am not against such an answer... it may be more difficult to construct a convincing answer though. – jerryjvl Jul 28 '09 at 9:00
  • Yet Steam/Valve is one of the most intrusive pieces of "copy protection"/DRM crap on the planet. – Adrien Aug 26 '10 at 18:12
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    This argument isn't very convincing. It contains an "appeal to authority" (I don't cares what some guy called Gabe thinks, I care why he thinks it.) It also begs the question by commenting on "When software is cracked..." but that doesn't address the question of whether it is possible to make crack-proof DRM. – Oddthinking Aug 27 '10 at 8:15
  • I don't understand why everyone so raging about Steam...I'm able to play my Steam-games without starting up Steam first. The only thing what's left then is the DRM of the game itself (if any). – Bobby Aug 27 '10 at 11:11

Okay, let me have a stab at combining (albeit inelegantly) the best points from the other answers... I'll make this answer CW so that if someone sees a chance to improve the polish (or content) they can (plus I don't want to gain rep for combining other people's answers).

  • With DRM, you're giving people the means to unlock the content you've protected, along with the content itself. Someone's going to find that "key" at some point, thus defeating it.

  • At some point, you have to decrypt the content. If the hacker(s) can get access to this data then they've defeated your DRM.

  • At some point, you also have to show the content to the user and then he/she can simply re-record it "in the clear" from that data. See Analog Hole (This is less of a problem with games, as interactive content can't easily be recorded then interacted with again at a later date)

  • DRM only punishes legitimate buyers, because adding DRM is only going to reduce the scope in which they can use your work and thus makes them less inclined to buy it.

  • All it takes is one person with the skill, tools, and time to crack it then it can be shared with anyone and there's no point in buying your version (except if you don't want to do something illegal of course! (Or if you honestly want to support the maker)).

  • Many people will opt to use a free version of your product regardless of the legality of using it without your DRM, because you are imposing unreasonable restrictions on how, where and why they use your work. Spore is a good example of this, as are many other programs/games/etc.

  • The points are shorter, but there is also one more point... diff seems to think you actually added about 62 characters ;) ... I think I like your use of the 'key' analogy instead of technical terms of 'encryption'... I am not entirely sure I like the stronger harder wording on some of the points, because this is meant to convince somebody that believes in DRM... this is not aimed at people that already believe what this is saying... I'll have to read it in some more detail... but I think some of the nuance was lost – jerryjvl Jul 29 '09 at 22:11
  • According to my text editor i used 407 less characters. Odd... – RCIX Aug 6 '09 at 1:13
  • It's strange, because it felt shorter to me too, but the revision history drop-down suggested it actually got longer. :) – jerryjvl Aug 6 '09 at 3:35

DRM creates an inferior product

In addition to 'it will always be cracked,' DRM has another flaw: it creates an inferior product.

Forget cost. Imagine you're willing to pay $X for a movie. Your options are:

  1. A physical disc that can't be saved to your hard drive, backed-up in case of damage, or shared, which needs an expensive player to watch, and which forces you to watch the previews. (My standalone DVD player puts a "no" sign on the screen when I try to skip them. Infuriating!)
  2. A digital copy that can be watched on a variety of devices that give the viewer full control, backed up with your other data, copied and shared.

Option #2 is a better product for your money. The fact that it's free (for some pirates) is just a bonus. Some people even buy a legitimate copy, then download a pirated one because it's easier to use.

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    +1 for buying a crappified version, then pirating the real one. I'm sure this happens more that people realise. – Rich Bradshaw Sep 20 '09 at 11:41
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    mplayer ignores the BS and just plays the film. Works with Windows too. – user4774 Oct 12 '09 at 18:14
  • I wish I could +2. I bought a BluRay player after moving from Europe to Canada, as my old DVD player was the wrong voltage. The BluRay device plays network media from my MediaTomb, so I can rip & watch most of my old DVDs. However, both the BluRay discs I bought (months after getting the player, so too late to return it) crash the player before reaching the main feature. Because of DRM, discs & players are incompatible, and I can't rip the titles with my current kit. I'm sticking to DVD, and if those stop being made, I may well stop buying until DRM dies. – Phil Lello Apr 30 '11 at 0:29

Cryptography, in essence, is about Alice sending a message to Bob so Eve can't tell what's being said.

In DRM, Bob (the person getting the message) is the same as Eve (who's trying to eavesdrop).

Therefore, DRM is not only impossible but sexually perverse.

(For when you think a bit of humor will drive in the point better.)

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    I really like this one... the only caveat being that it most likely requires someone with some knowledge of Cryptography to be able to fully appreciate the argument :) – jerryjvl Sep 20 '09 at 23:42
  • @jerryjvl: Hmm. I don't see why cryptography knowledge is required to understand the argument; is it not merely required that one be familiar with the naming conventions in order to get the joke? – SamB Aug 25 '10 at 4:10

This is not a technical, more a social answer, so it might not be exactly what you asked for:

Nobody who would illegaly copy a piece that's not DRMed, would even pay a penny for it if it were DRMed. They'd find a way to get it for free or not get it at all.

So, you're not winning anything (as in: cash) by DRMing; however, you're driving away the honest customers, because even if there were such a thing as a secure DRM, it could never be frictionless for the user.

  • Although it does not answer the question as stated, I like it... good addition for the arsenal of rebuttals :) ... there may even be a way to compress this answer into a shorter and punchier sentence still. – jerryjvl Jul 28 '09 at 6:10
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    Last night at the club entrance. Guest to bouncer: "How come you're strip searching me that I paid my ten bucks to get in, while the kids who sneak in through the back door can run around unsearched?" Bouncer to guest: "Because they're not allowed here." – balpha Jul 28 '09 at 6:22
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    @balpha: lol ... not sure that'll convince anyone either, but I like it. – jerryjvl Jul 28 '09 at 6:26
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    Have you got evidence to back up your claim? – Andrew Grimm Aug 26 '09 at 1:05

DRM solves an imaginary problem

If a song or piece of software has been pirated 10,000 times, that does not equal 10,000 lost sales, for several reasons.

  • The demand curve. A product that sells 10,000 copies at $1 might only sell 500 copies at $10. This is basic economics.
  • The free factor. The biggest leap on that demand curve will be between $0 and $1. If something is free, it is zero-risk. Lots of people will get it on a whim to see if they like it. Even a price of $0.01 could drop the number of downloads considerably, if it means having to negotiate a transaction.
  • Viral impact. Although a free product may undermine some of the market for a paid version, it can also create a market. Consider Windows, which has been pirated widely in places like China, spurring on legitimate sales. What if they had just used Linux? Or consider Adobe Photoshop. It's an industry-standard piece of software that costs more than $500. Businesses will pay for it, but high school students probably can't. Which scenario is better for Adobe?
    • Students never get their hands on Photoshop until they get to college or the work force, at which point, having no preference, they'll use whatever software someone provides them
    • Students pirate Photoshop and started tinkering at age 12, know it inside-out before they ever get to college, put it on their resume, and scoff at the suggestion of using anything else when they're in the work force

DRM assumes that "piracy is always bad," when in fact, piracy has pros and cons. In general, though, it seems that "everybody pirates our product" is preferable to "nobody has heard of our product."

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    VALVe have put a few figures out from Steam - when they slashed L4D's pricing, it grossed more than it did on release day. – Phoshi Sep 20 '09 at 13:31
  • @Phoshi, Jeff explains those figures: codinghorror.com/blog/2009/08/… – Mircea Chirea Aug 24 '10 at 14:29
  • Hmm, there is one risk involved: you might catch something. – SamB Aug 25 '10 at 4:05

Ok, I will use short sentences:

  1. DRM is based on encrypted content

  2. The DRM will decrypt the content only if a valid license is present

  3. Once the decrypted content can be copied, the DRM is broken

  4. The content needs to be decrypted in memory, in order to do anything meaningfull with it (play a song/movie etc)

  5. A person that has physical access to a machine can get direct access to all data in it's memory

  6. If someone has direct access to the decrypted content, he/she can make an unlimited number of copies of it

The most difficult things to grok for a layperson are 5, and maybe 4, IMO.

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    I had not considered a numbered list... this actually works a lot better than I would have expected. Note that maybe there's something to be said for step 4/5 being replaced with the argument that if nothing else you could copy the physical manifestation of the playback regardless of whether it is easy/possible to do so inside the device. – jerryjvl Jul 28 '09 at 10:30
  • Fair point, I was obviously thinking too technical ;-) – Treb Jul 28 '09 at 13:24
  • -1 You used the word "grok". Now no lay person will ever understand! – user169983 Nov 23 '13 at 19:20

I always liked something that Leo Laporte said on his radio show one day. (Paraphrasing from a fuzzy memory here...) He wondered why the MPAA didn't just require that every DVD package contain pepper spray to zap the buyer in the eye since the DRM really only punishes the legitimate user without slowing down the pirate at all.

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There are two reasons why DRM cannot work:

  1. If you have unrestricted access to a computer, you can do anything to it. If for instance the operating system prevents you from doing some operation, you can alter the operating system so it allows you to. This is related to something mentioned on 10 Immutable Laws of Security: "If a bad guy has unrestricted physical access to your computer, it's not your computer anymore".

  2. Even if you are not tech-savvy enough to know how to do it, someone somewhere is, and he will distribute the result. This is mentioned in The Darknet and the Future of Content Distribution: "Any widely distributed object will be available to a fraction of users in a form that permits copying."

If you can see or hear it, you can copy it. Not always with exact the same quality, but it will be possible, thanks to the analog hole. You can mount a camera and film the TV/PC screen, or you can use a good old tape recorder to copy DRM-infected music.

People also want to have full control over items they've bought legally. Would you like to have a book you could read only three times or on Tuesdays only?

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    "If you can see or hear it, you can copy it." Excluding software, this is a great summary. – Nathan Long Oct 5 '09 at 17:27
  • Or would you only want to be allowed to read the book if you were sitting in the same chair you started it in? – SamB Aug 25 '10 at 4:16
  • First part is a strong point. The second part doesn't address the issue of whether DRM is viable. It also doesn't address the way the market works. For 10 cents, I would happily buy a book I could only read 3 times, or on Tuesdays only. Heck, I often pay for a newspaper with more words than a book that I only partly read and then throw away. – Oddthinking Aug 27 '10 at 17:46

If Hollywood studios and game publishers cant stop it neither can you.

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    This is very simple, but there's something to it. "Regardless of what I say and you argue back, smarter people than us have tried this many times and have always failed." – Beska Jul 28 '09 at 21:01
  • @Beska: Well, I'm not sure about smarter, but they have waaaaay more money. (Despite their DRM not really working.) – SamB Aug 25 '10 at 4:14
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    ... and that is why heavier-than-air machines will never fly. (It isn't a particularly strong argument that DRM is impossible. It is a strong argument that DRM is very hard.) – Oddthinking Aug 27 '10 at 17:31

The best way I find to explain technical concepts to non-technical people is to use analogies with which they have an understanding, generally because it forms part of what they perceive to be "common sense"

From a technical standpoint, the weakness in DRM is that people are likely to reverse-engineer any given DRM scheme when given adequate motivation, time and resources, so:

"DRM technologies are not a good solution because like any lock, a person with enough time, motivation and skill will break that lock"

Or taking another approach: if one buys something, there is a general expectation that one should be able to use that item for whatever purpose they see fit, DRM often prevents this:

If you buy an apple there is no reason you cant eat it whole, cut it in half, or eat it at a friends house, anybody who tried to tell you you couldn't do any of these things would be denying your rights

With DRM controlling where music can be played, the recrd companies are trying to tell consumers where they can play the music they have baught, if you won't accept it from a supermarket, why a record label?

Hope this helped.

  • Thanks for the contribution; so far all answers have interesting and useful elements... but none of them strike me as comprehensive... but maybe something can be cobbled together from multiple answers once we have a few more... – jerryjvl Jul 28 '09 at 6:14
  • Hmm. I never thought Apples looked particularly tasty... and try sinking your teeth into one, they'll just slide off all of those curves! – SamB Aug 25 '10 at 4:12
  • The first argument has just converted the question from "Does the perfect DRM exist?" to "Does the perfect lock exists?" I am not sure that is any more easy for a typical person to understand. For most people, locks are perceived as something that DOES work. – Oddthinking Aug 27 '10 at 17:34
  • Your second argument is empty rhetoric arguing against the concepts of copyright in general, not against DRM. Intellectual Property does not work the same as normal property. The closest analogy, from the perspective of the copyright owner, is someone who steals apples, not someone who shares them. – Oddthinking Aug 27 '10 at 17:37

It actually does work up to a certain degree. The goal of DRM is not to prevent a person to run/copy the software, but to make it more difficult and annoying to do so.

If there isn't a crack yet then you will have to reverse engineer the protection mechanism and create one. Most people don't know how to do it, and most of the people who do find the process too annoying and prefer just paying for the software. If there is a crack, all the people who download it risk getting infected by a trojan or virus.

The real world is full of protection mechanisms similar to DRM. For example in my city they sell a $50 device to pay parking fees:

alt text

When you activate it, it will display how much money you are paying per hour, and how much money you have left. When you run out of money you throw it away and buy a new one.

That's a hardware device that is in your hands. By definition, it is absolutely possible to "hack" it so that you have infinite money. But hey, no one does it! So the "DRM" is working in this case.

Other examples of DRM-like technologies are cash: you can in theory make fake bills that are exactly the same as real bills. It's just extremely difficult. And the list goes on: passports, IDs, etc.

So the goal is not to make it impossible, it's to make it difficult, and in this case DRM does work.

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    The problem with your cash analogy is that while cracking software is difficult, once it is done, it is available to everyone, regardless of their skill level. Counterfeit bills, even once created, cannot be simply and easily obtained by everyone with access to a torrent. – Jason Berkan Aug 26 '10 at 16:59
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    Andreas makes a good point, but so does Jason. I'd like to point out that when the argument is that DRM circumvention is dangerous because of malware, there's a big difference between DRM in software and DRM in data. Cracked software might be a risk, but DRM-removed content really isn't (other than in fringe cases). And as I understand it, the question is about data. – Ilari Kajaste Aug 27 '10 at 7:15
  • As anecdotal evidence, I do know of people not getting DRM-cracked software because of the risks... However, I don't think I know of any actual case where someone would have actually bought DRM software because it was too hard or dangerous to copy. And on the contrary, I do know cases where people have especially copied content instead of buying because DRM was too restrictive... – Ilari Kajaste Aug 27 '10 at 7:22

This general question in Stack Overflow links here and the first answer, that Microsoft couldn't, is the right answer for your question. Qwerty above suggests Spore. Brant Bobby gives a rational and detailed answer to your very question - like many of the answers here, ideal to convince people who think like us of the utter futility of DRM, copy protection, etc.

So - why am I still here? It's because you asked the question wrong - and I know what you should know too. You probably aren't trying to convince someone that DRM cannot work at preventing copies. Instead you're probably trying to convince them that DRM isn't worth it, which is much more difficult, and the Spore and Microsoft examples aren't useful there. What you need are facts.

Here's a fact that makes managers loose sleep at night. Approximately 90%. That's how many of your users might be pirating your goods. 90%. Here's where things go wrong - the manager thinks - if we could convert those 90% pirates into sales, why, our money problems would be solved! If we could only convert even a fraction of them! And so, the decision is made - DRM will increase conversions and reduce piracy some, so they want it. We need to rain on their parade with another number. 0.1%. That's 1 in every 1000, and is roughly how many of those pirates will convert if you break their free distribution of your data. So, let's do the math - 1000 paying users + 9000 pirates * 1 / 1000 = 1009 paying users... Let's ask yourself - are those nine sales justifying the cost of the DRM - including the loss of network externalities (make sure to use that phrase - if they were trained in business school, it's their Power Law).

If your data that needs to be protected is selling for enough per copy, those 9 customers might pay enough to make it worth it. Or, if you have 1,000,000 paying customers, you'd earn 9,000 sales, certainly worth it even at $5 per copy, right? Let's drop the other shoe and provide another case study: 2D Boy's World of Goo. They make the blatant claim to having no DRM. And their piracy rate was a mere... 90%. That's about the same piracy rate as Reflexive - who were releasing from the start with DRM. Actually it's possibly lower, down to 82%. No statistical difference. They didn't follow the industry accepted practices, but it still worked just the same.

The time comes then to make a decision - to accept DRM and the tricky problems it brings, assuming and hoping that the conversions come in to justify the price - or alternatively to take the plunge and assume that your customers aren't different from those of Reflexive and 2D Boy, and maybe save the full cost of DRM to use on the next big thing. With what you know now, I'd pick no DRM - but I could be wrong in doing so.

  • +1 I liked 2D Boys decision of not using DRM which is (among the greatness of the game itself, of course) one of the reasons why I bought this game. And why I will probably never play Assassin's Creed 2. Ever. Take that, Ubisoft. Beaten. By. Independent. – Tobias Kienzler Oct 29 '10 at 8:10

If you hide the key near the lock, eventually somebody will find it. Per your comment, you can't give me something that's locked such that I can't open it otherwise I can't use it. I just have to spend the time to figure out how to unlock it and eventually, I will.

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    Short... but not sure this'd explain anything to the hypothetical politician. – jerryjvl Jul 28 '09 at 5:49

The Cracker Principle: Ultimately, the decision to grant access to content is manifested as a single 0/1 value in the memory of the computer (and can be manipulated).

Don't Trust the Client: The media must be run on hardware and software that the user (not the industry) controls.

Inevitable Failure: Once broken, it is frequently easier to pirate the content wholesale rather than legitimately purchase it. (ie. patched XP iso vs. purchase and activation) It may be infeasible for the licenser to correct the DRM's flaws due to compatibility concerns.

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  • Not neccesarily for point 1: A bool in .NET is 8 bits... – RCIX Nov 12 '09 at 6:24
  • Regarding the first point, the yes/no decision could be on a remote server the user does not have access to if the content is encrypted or must otherwise be downloaded. Though, once downloaded or decrypted, copying becomes possible anyway. – Sydius Jul 28 '10 at 23:19
  • I think the second point is quite key. However, many of the answers here ignore the non-intuitive practicalities of reverse-engineering a code from a chip. – Oddthinking Aug 27 '10 at 17:42
  • The cracker principle above is fundamentally untrue. A decision to grant access could be possession of a standard crypto key like an RC4 key, decrypting with the wrong key results in garbage, not a 1 or 0 that can be overridden. – davenpcj May 7 '11 at 19:05

I always use the point that if you can see it (for TV/movies) or listen to it (for music) then you can copy it.

It might not always be the highest fidelity copy (camera pointed at screen, microphone in front of speakers for example), but if someone wants to copy it badly enough they'll find a way.

Obviously if there's a high value to the copy then it's worth investing in time and equipment to get a higher fidelity copy as you can sell this for even more than a ropey copy.

The link to Wikipedia provided by CesarB, goes into a lot more detail on this.

  • Ah, that's what I was trying to say in Treb's list. – jerryjvl Jul 28 '09 at 10:31
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    The technical term for this is "analog hole". – CesarB Jul 28 '09 at 17:30
  • @CesarB - I didn't know it had a name. Thanks. – ChrisF Jul 28 '09 at 17:31
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    @ChrisF: en.wikipedia.org/wiki/Analog_hole has way more than you ever wanted to know about it. – CesarB Jul 28 '09 at 18:45

DRM is like running a haunted house. You want everyone to go in through the entrance and leave through the exit. But sooner or later someone is going to try the "Employees Only" door and let all his buddies in without paying.

Then before you know it your mummy has been unwrapped Dracula is dressed like a circa 1970s pimp and Frankenstein looks like Bozo the clown.

Dang you pesky kids... and your dog too!


If the music is to be playable, then some software must be able to read it unencrypted and load it into memory.

If your software can do it, another piece of software also can, and once it does, it can make unlimited copies of it.

Even if you design it so that only a certain hardware can decrypt it, at the end of the day, that hardware won't do anything that a piece of software can't (this is hard to explain for mere mortals I guess), because the hardware is only manipulating data, a software can also do the exact same manipulation.

Even if you manage to create the perfect copy-prevention mechanism. Guess what, as soon as the music/video is playing in a device, it can be [re-]recorded, easily, and with high quality.

  • Unless ofcourse you create hardware to protect content... as has already been tried in consoles... with the right hardware you could not decrypt the data until it reaches the connector to the monitor (or in the case of HDMI even until it is inside the monitor) – jerryjvl Jul 29 '09 at 0:06
  • good point, updated the answer. – hasen Jul 29 '09 at 4:41
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    @jerryjvl: software could still do it -- it's just that it might be hard to find the necessary cryptographic parameters. The most anyone can hope to do is force those who would seek to do this to spend a lot of time and money peeling the chip responsible... – SamB Aug 25 '10 at 4:22
  • @SamB, unless of course you require that the hardware "phone home" for an updated key every so often...and that it becomes totally inoperative if tampered with. Built in EMP booby trap, anyone? – Wildcard Apr 8 '16 at 5:17

DRM is like poisoned food, that is tuned to feed you, but kill everybody else. So you can't share food with somebody who is starving. DRM puts you in a situation when YOU are the guilty one, if somebody dies from your poisoned food, because formally, it's YOUR food.

Replace "food" with "information" and here you go.

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    Yikes, you're saying DRM can KILL ME?! ;) – Ilari Kajaste Aug 27 '10 at 7:24
  • Ha! So the analogy here is between someone who wouldn't mind seeing a movie without paying and someone who is starving? My god, the MPAA have a moral obligation to ensure EVERYONE sees EVERY MOVIE! Why must so many people in need suffer this way? – Oddthinking Aug 27 '10 at 17:53

I'd like to make an argument for why DRM is actually achievable.

Usually the argument against is something like "you are distributing a locked box along with the key to open it and this cannot work in the long term."

However, with regards to PC software, if the OS is redesigned around a complete DRM solution then it could be made unbreakable.

Say a company is publishing a video game. What they need to do is control the content from beginning to end. The OS would be given access to an online store or repository of some sort, and the content would be sent encrypted, and then it would be stored encrypted on the hard drive, via some sort of hardware mechanism like a TPM chip. Some portion of storage would be encrypted with the TPM and therefore the video game's binaries would be inaccessible by the user even if they read from the storage directly while the computer was off. When loaded into memory, the OS would protect against the user reading or writing the memory. The only user visible manifestation of the software running would be what it is displaying on the screen. This would be less of a protection for copyrighted movies, but for interactive content like video games it is enough. For this to work every dll or binary that the game loaded would have to also be stored in the protected space so as to be unmodifiable by the user. If they were modifiable, then a pirate could simply inject his own code into them, which would then be loaded into the game's process, and the barrier between the DRM'd software and the user accessible part of the system would be broken.

It would take some work, but I believe it would be unbreakable. The only thing I would worry about is that it would allow OS companies to hide things on your computer which even a highly sophisticated user would not be able to detect.

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  • This is a strong argument in the context of interactive content, since part of the experience is how your inputs affect the produced outputs. However, this still theoretically falls afoul of the "locked box" argument against DRM being feasible. Ultimately, everything that encodes this interactive experience is contained in the machine, and when you power it on, its circuitry must be able to unlock and execute that content. Though undoubtedly technically challenging, I could intercept unencrypted instructions somewhere in the hardware prior to execution. – jerryjvl Feb 7 at 7:16

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