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BBC iPlayer Mobile Downloads & DRM

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Matthew Postgate Matthew Postgate | 13:10 UK time, Monday, 13 October 2008

Mobile BBC iPlayer has been around in various forms since March on the iPhone and iPod touch.

It's proved very popular, yet we've always been aware that by only offering streaming, it misses out on one of the key use cases of mobile and portable devices - offline playback of programmes on planes, trains etc.

The Nokia N96 is the first device we've come across that really ticks all the boxes in terms of having all the features and capabilities we need to offer this: it's got a powerful browser, 3G and WLAN support and, crucially, it supports the OMA DRM 2 specification.

The BBC only has rights to make TV programmes available in iPlayer for a limited number of days after the original broadcast - so, when we provide downloadable programmes, we have to use DRM (Digital Rights Management) technology which ensures that the programme is only available to users on the phone for the allowed number of days.

open_mobile_allaince.pngOMA DRM 2 is such a DRM solution. It was designed a few years ago by the Open Mobile Alliance (the main mobile industry group that creates such things) and has been emerging in phones for the last year or so, now including the Nokia N96.

Until now, it's largely only the mobile operators that have been using it, but in order to provide the download experience we want to offer, we've decided to license the technology and build the server systems necessary to package and distribute our programmes in the OMA DRM 2 format.

As well as enabling us to provide downloadable programmes to the N96, the OMA DRM 2 system is available on a growing number of handsets, and so we expect our investment here to help enable us to provide mobile BBC iPlayer on a range of mobiles.

drm_partners.pngIn order to build the necessary DRM servers, the BBC has taken licenses from three companies: CoreMedia, who provided us with a software development kit which allowed us to build the system in a few short weeks; Intertrust, which is a leading inventor and patent owner of technology in the OMA DRM 2 specification and CMLA (Content Management License Administrator), which is the leading Certificate Authority (CA) and "Root Of Trust" for the OMA DRM 2 system. I think this last one warrants a little more explanation.

On a technical level, the OMA DRM 2 system uses a certificate system similar to that used in SSL and other secure communication systems to identify the various parties involved in the download of DRM content to a phone (device model, device manufacturer, content distributor, CA etc).

The certificates provided by CMLA are preinstalled on the phones and integrated with our server system, and this allows each party to identify each other and confirm that the certificate is genuine and issued by CMLA - and, crucially, the server and phone are able to check the other party's certificates status with CMLA to determine whether the certificate is still trusted. This is the essence of "trust" in a DRM system.

The content creators and owners "trust" CMLA to manage the certificate status of devices and service providers like us so that, should a device implementation become compromised, or a service provider go "bad", they can be taken out of the system easily and without any explicit action by any other party (e.g. the BBC).

There is a lot more subtlety, complexity and technical detail underneath the surface in this topic. Interested readers will find more detail on the internet.

Matthew Postgate is Controller, BBC Mobile.


  • Comment number 1.

    I assume you are talking to Apple to get them to agree to use this drm so other iphone users like me can benefit?

  • Comment number 2.

    I don't think even the BBC could get Apple to adopt OMA DRM 2, I would't hold your breath.

    As a fellow iPhone owner I would dearly love to see it but as even Adobe can't get Apple to include Flash I think it's a none starter.

  • Comment number 3.

    What's interesting to me is the fact that rights holders insist on DRM for mobile devices - but not for "fixed" devices.

    FreeView and Satellite are DRM free. Most of the PVRs on the market will allow me to record SD or HD material and place shift it. From there, if I really want, I can make it mobile.

    The BBC has been very vocal about not having encryption on mainstream broadcasts. It allows multiple manufacturers to create receivers without having to pay huge licensing fees. Something not possible with DRM.

    But this doesn't happen on mobile. Why?

    From a technical perspective, the BBC could make 320*240 3GP files available which would play on every phone. But then, people could share content for free and - so the argument goes - rights holders would lose money.

    Except... Is there any evidence that happens? I'll bet that everyone has borrowed a VHS or DVD recorded from an off-air source. What's the difference with digital content?

    A DVD recorded from FreeView will be higher quality and - presumably - more valuable than a low-resolution copy for mobile. But there are no restrictions on DVD recorders.

    Is it a case that rights-holders need to be shown that there's more value in making things DRM free - cheaper to make the content available, wider distribution, fewer technical problems - and that DRM is very easy to break?

    Or is there something else at work here?


  • Comment number 4.

    My comments are enclosed in the following DRM scheme: ROT13 encryption from http://www.retards.org/projects/rot13/.

    The copyright license for use of this comment precludes your decryption of the comment below for purposes other than adding it to the commentary of the BBC weblogs page it was submitted to.

    V snvy gb frr gur arrq sbe QEZ va ybj-dhnyvgl svyrf fhpu nf jbhyq or hfrq ba zbovyr cubar cyngsbezf. Ab cubar unf n fperra lrg gb nccerpvngr rira 720c UQ zbivrf, naq srj unir gur cebprffvat cbjre gb eraqre ZCRT2 be ZCRT4 ng gung erfbyhgvba. Fb gurer'f ab erny ybff va grezf bs pbafhzre rkcrevrapr vs gur qvtvgny svyrf fubja ba na A96 ner genafsreerq nebhaq gur vagrearg. Gurer vfa'g n zvffrq fnyr bs n QIQ be n Oyh-Enl orpnhfr gurl ner fb zhpu orggre dhnyvgl. Naq gur OOP vfa'g tbvat gb fgneg punetvat na nqqvgvbany yvprafvat srr bire gur bar nyernql cnvq. Fb jul hfr QEZ?

    Gurer'f nabgure zber-vzcbegnag dhrfgvba nobhg QEZ: V'ir tvira lbh gur xrl naq gur ybpxrq-hc pbagrag. Fb jul ner crbcyr pbasbhaqrq vagb oryvrivat gung guvf fbzr xvaq bs cebgrpgvba ntnvafg fb-pnyyrq abg crezvggrq' hfrf bs gur ybpxrq-hc pbagrag?

    Abgr gung, vs lbh'er ernqvat guvf, V pna'g abj fgbc lbh sebz cbfgvat hc gur bevtvany irefvba bs guvf grkg.

  • Comment number 5.

    k3ninho - Genius!

  • Comment number 6.

    My N95 8GB has OMA DRM 2, but the IPlayer downloads do not work (according to the forums they do not work for any N95 user). Why is this and when will it be fixed?

  • Comment number 7.

    k3ninho - while that's very clever and I'm sure makes a very pertinent point about pointless encryption, it doesn't really boost your chances of a meaninful reply (except from sad gits like me) - for precisely the same reason as DRM is worthwhile: most people just can't be bothered to hack it/break the code.

    DRM is like a sign saying 'don't walk on the grass'. It doesn't actually stop you from playing football (or finding ways to distribute DRM-protected content). It just suggests that someone somewhere would prefer it if you didn't. Most people will do as the sign/DRM suggests.

  • Comment number 8.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • Comment number 9.

    This comment was removed because the moderators found it broke the house rules. Explain.


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