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annk
Aug 13, 2007, 07:22 AM
I'm worried I haven't worded this well, but please bear with me: :o

Background:

At my place of work, we're investigating a system for loaning out digital files to library patrons. Mao - this is a legal situation, and will be regulated by agreements with the copyright holders.

The files will be downloaded by the patrons to their private computers, then (for those who wish to do so) transferred over to their portable players. We're being told that it will only work with .wma files, that "Apple is so difficult", "This won't work on iPods", etc.

The system we're considering using, that distributes the files to patrons, will implement a "time bomb", so that the file is only playable for the allotted loan time (1 day, 3 days, 7 days etc), and can only be played by the person who was authorised to borrow the material. The law here doesn't allow watermarks with info about individuals who borrow. Right now, this time bomb is .wma only.

Question:

Two of us on the project are trying to avoid a situation where we are locked to Windows, and where iPod users can't use the service. It's becoming obvious that solving this is not a priority for the vendor, so we need to investigate ourselves. We wonder how feasible it is to require that the vendor include the possibility for the patron to choose either .wma or .aac at the time of download. I understand that Apple uses Fairplay DRM in their .aac files, and that this implements the limits they choose on the music purchased via iTMS, but is it possible for us to use something like Fairplay, that will let us put our own parameters in? If so, what's out there?

I obviously won't be the one doing it :p, I just need to know where to start looking to read up and understand.



whooleytoo
Aug 13, 2007, 08:41 AM
Fairplay isn't being licensed, AFAIK, so that's not an option.

It would be relatively simple to implement your own DRM scheme on a Mac/PC, since you can control the player software. To do so on a portable player might be far more difficult. Since you can't install any player software on an iPod, your only control of the content is when they are synced. If the iPods aren't synced, the content never expires.

Sorry, I don't know how you are going to get around this. :o

kainjow
Aug 13, 2007, 08:55 AM
Check out Doubletwist (http://www.doubletwistventures.com/)

From Wikipedia:

DoubleTwist Ventures is a digital media interoperability company notable for having reverse engineered Apple's FairPlay DRM system. According to Fortune Magazine, DoubleTwist is offering two software products: one that would let other companies sell FairPlay-protected songs that play on the iPod, and another that would let competing hardware devices play FairPlay content.
DoubleTwist employs Jon Lech Johansen, also known as DVD Jon, as a software engineer.

russell.h
Aug 13, 2007, 03:30 PM
A good DRM scheme is not at all simple to implement as you have to be careful about where you store decryption keys, and ensure the security of the data stream the entire way from your server to the screen. This means the data has to be encrypted any time it is transferred over a user accessible bus. Even then you have to have the decryption keys in memory at some point, so you are fighting what is generally agreed to be a losing battle. At this point both windows media DRM and Fairplay are "broken" and files protected with either can be easily decrypted with freely available tools (although, of course, this is a violation of the DMCA in the United States).

Eraserhead
Aug 13, 2007, 04:34 PM
Surely you could just store the date the file was to be deleted in the comment of the metadata (or a more obscure entry) and then use a format like .ogg which virtually noone uses, and then just provide a "special player" to play it which checks the date and deletes the file at the required point. You could create a new wrapper format and use a weird ID Tag field to make things more complex, and that would work pretty well IMO.

russell.h
Aug 14, 2007, 10:21 AM
Except when you are distributing material you don't personally own the copyright to it isn't up to you to decide what is an acceptable DRM scheme, its up to the copyright holder. In most cases they aren't going to accept anything other than Fairplay, WMDRM and maybe a few others they have on a list that I'm sure they keep.

annk
Aug 14, 2007, 12:20 PM
Thanks for the replies, everybody.

Surely you could just store the date the file was to be deleted in the comment of the metadata (or a more obscure entry) and then use a format like .ogg which virtually noone uses, and then just provide a "special player" to play it which checks the date and deletes the file at the required point. You could create a new wrapper format and use a weird ID Tag field to make things more complex, and that would work pretty well IMO.

By special player, I assume you mean software? It would be okay to require the patrons to downloada specific software we've had developed for this purpose, as long as it lets the patrons use their borrowed material as either .aac or .wma, on their portable devices.

The point here is that a system for managing circulation (= borrowing from the library) is in place, and we want our patrons to be able to download their virtual loans, and transfer them to their portable players, regardless of OS, and to be able to use the portable players with the biggest market share. Right now, the vendor says the patrons can only download .wma files, and can only play the files on iRiver and Creative devices. We shake our heads at this, and wonder why a library service would exclude the huge number of patrons who want to listen to their borrowed files on Nokia and Sony Ericsson phones, and on iPods.

Except when you are distributing material you don't personally own the copyright to it isn't up to you to decide what is an acceptable DRM scheme, its up to the copyright holder. In most cases they aren't going to accept anything other than Fairplay, WMDRM and maybe a few others they have on a list that I'm sure they keep.

We are not attempting to decide the limits determined by the copyright - as I said, the circulation of this material will be governed by agreements with the copyright holders. What we want to do, is to be able to implement those limits in files other than .wma, so that we don't have a situation where only Windoze users with iRiver or Creative portable devices can use the new service.

russell.h
Aug 14, 2007, 01:21 PM
If what you are trying to do is have your files playable on iPods, then there is no way to legally do so in the United States. Apple does not License Fairplay, and when Real invented a compatible technology Apple threatened to sue them (and would have won probably, under the DMCA reverse engineering a DRM scheme is illegal). I'm not sure what the legal status of DoubleTwist (mentioned above) is, but I doubt you want to be associated with them, at least until they get somewhat better established.

The problem here is that Apple is (understandably) unwilling to support Microsoft's DRM scheme on iPods. They are also (again understandably, sort of...) unwilling to license Fairplay, although this would seem to be simply a matter of discouraging competition. This may change at some point in the not so distant future though, as France, Norway and Germany are all contemplating legal action against Apple (ie banning iTunes?) for anti competitive practices regarding Fairplay.

annk
Aug 14, 2007, 01:34 PM
If what you are trying to do is have your files playable on iPods, then there is no way to legally do so in the United States. Apple does not License Fairplay, and when Real invented a compatible technology Apple threatened to sue them (and would have won probably, under the DMCA reverse engineering a DRM scheme is illegal). I'm not sure what the legal status of DoubleTwist (mentioned above) is, but I doubt you want to be associated with them, at least until they get somewhat better established.

The problem here is that Apple is (understandably) unwilling to support Microsoft's DRM scheme on iPods. They are also (again understandably, sort of...) unwilling to license Fairplay, although this would seem to be simply a matter of discouraging competition. This may change at some point in the not so distant future though, as France, Norway and Germany are all contemplating legal action against Apple (ie banning iTunes?) for anti competitive practices regarding Fairplay.

We're not in the US, we're in Norway.

So if I understand you correctly, the only way to get an .aac file with DRM to play on an iPod, is to use Fairplay, which we can't, because Apple won't license it. Is that right?

Eraserhead
Aug 14, 2007, 01:44 PM
By special player, I assume you mean software? It would be okay to require the patrons to downloada specific software we've had developed for this purpose, as long as it lets the patrons use their borrowed material as either .aac or .wma, on their portable devices.

Yeah, but its doubtful you could get portable device support.

We are not attempting to decide the limits determined by the copyright - as I said, the circulation of this material will be governed by agreements with the copyright holders. What we want to do, is to be able to implement those limits in files other than .wma, so that we don't have a situation where only Windoze users with iRiver or Creative portable devices can use the new service.

Well I suspect they wouldn't be happy with my system anyhow, though it would work fairly well...

We're not in the US, we're in Norway.

So if I understand you correctly, the only way to get an .aac file with DRM to play on an iPod, is to use Fairplay, which we can't, because Apple won't license it. Is that right?

Yes, and even if they did because Fairplay doesn't allow you to create a "time bomb" it still wouldn't be possible.

Another possibility is Real's Helix DRM system (http://www.realnetworks.com/products/security/index.html), though whether that will survive is another matter, it seems to support "time bombs" too. Though you aren't going to be able to get iPod support with that.

annk
Aug 14, 2007, 02:06 PM
Thanks for the time you all took to post answers. But I have to admit I'm very discouraged. I REALLY don't want our library to offer a service that only Windoze users can enjoy, but it just doesn't look like there's any way around it. :(

russell.h
Aug 14, 2007, 02:18 PM
Give it time, you aren't the only one with this problem, this is a huge issue right now.

There are really 2 problems at the moment

1. Technical - Fairplay is the only supported DRM on iPods, and Fairplay has no support for "timebombs" (or so says Eraserhead, and I can't find anything to indicate otherwise).

2. Legal - Apple doesn't license Fairplay anyway.

There are rumors that Apple might begin some sort of rental service. That would take care of the technical problem. And Apple is (potentially) in all sorts of legal trouble in Europe over this, so hopefully they will be forced to begin Licensing Fairplay. There go the legal and technical issues.

Eraserhead
Aug 14, 2007, 04:54 PM
Thanks for the time you all took to post answers. But I have to admit I'm very discouraged. I REALLY don't want our library to offer a service that only Windoze users can enjoy, but it just doesn't look like there's any way around it. :(

Whats wrong with Helix? That has a Mac/Linux version, at least for computers...

annk
Aug 15, 2007, 12:19 AM
Whats wrong with Helix? That has a Mac/Linux version, at least for computers...

I will look into this. If it can do what we want in relation both to the download and the playing of the file on the portable players, I'll be thrilled (and I'll post again in that case).