DRM - limit but not locking

DRM - limit but not locking SearchSearch
Author Message
Jeff Mitchell
New member
Username: Squared99

Post Number: 6
Registered: 04-2006
Posted on Monday, September 15, 2008 - 01:42 am:   

Hi,

Might be a dumb question, but from reading the NOWSMS docs all constraint and limit params for the the DRM utility also imply forward locking. Is it possible to limit or constrain without forward locking?

The idea being to allow a piece of content to be forwarded but eventually expire.

Cheers
Bryce Norwood - NowSMS Support
Board Administrator
Username: Bryce

Post Number: 7659
Registered: 10-2002
Posted on Wednesday, October 01, 2008 - 09:27 pm:   

Hi Jeff,

If you have any questions that pertain to NowSMS, please feel free to post them in one of the product support areas of the forum. We don't visit the "Not for product support" areas as frequently.

Des told me that this was an interesting question, so thanks for that ...

That said, this question is probably more one of what the OMA DRM standard allows vs. what NowSMS allows.

My interpretation is that you can't really do what you want. Or maybe you might be able to, but not exactly like you want.

Combined delivery implies forward lock. If you have any constraints defined on the object, forward lock is assumed.

Where you can sort of do what you want is with the concept of "superdistribution".

Superdistribution is built on top of separate delivery.

If you have a "Rights-Issuer:" header in your separate delivery object, then the object is considered to be a superdistribution object.

A user who has this object can forward the object to another user.

However, the object is encrypted, and is not activated by default for the receiving party. It must be activated by the receipt of a separate delivery rights message. When the receiver tries to access the message, the device indicates that it needs to acquire rights to activate the object, and it connects to the "Rights-Issuer" URL.

Unfortunately, the "Rights-Issuer" URL can't just return the rights object in its response. (At least I was unsuccessful with his attempts to do so, although it's been a year or so since I tried.) According to the specs, the rights object can only be received via WAP push.

So the scenario would be that for delivery to the initial recipient, the object goes out using separate delivery, but includes a "Rights-Issuer:" URL in the object header. (That's what the -headerFile command line option is for in DRMCOMP.)

If the object is forwarded to anyone else, they will connect to "Rights-Issuer:" URL to acquire rights. The script at that URL needs to be able to generate a WAP push that gets delivered back to the device in order to activate the object. If you are partnered with a mobile operator and can automatically get the user's MSISDN, then it's easy ... otherwise you have to ask for the phone number to which the rights object should be sent.

-bn
Jeff Mitchell
New member
Username: Squared99

Post Number: 8
Registered: 04-2006
Posted on Wednesday, October 01, 2008 - 10:06 pm:   

Thanks Bryce, Apologies for posting in the wrong area. I caught on after the second time, I'm a bit slow that way :-)

Appreciate your responses. Many Thanks