Douglas Crockford




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Pronouns: pe/per


November 2004


Following the lead of the RIAA, MPAA has begun suing individuals for sharing movies on the Internet P2P networks. MPAA is also planning to release spyware that will infect computers and search them for copyrighted material. MPAA is encouraging parents to rat out their kids. I believe that MPAA is making a serious mistake in attacking individuals.

DTV Link

DTV Link is a logo introduced by CEA 3 years ago. It standardizes the use of Firewire for video. The logo can be used with any product that is capable of interfacing with other products with the following minimum attributes: Utilizes a 1394 serial connection; conforms to the applicable EIA/CEA technology and standards profiles based on EIA-849; and uses DTCP (Digital Transmission Content Protection).

EIA/CEA-775-A is a digital interface based on the IEEE-1394 standard adopted by CEA and the National Cable Television Association (NCTA) for connection of a digital cable box and a digital television.

EIA/CEA-849-A specifies profiles for various applications of the EIA-775-A standard. The application areas covered here include digital streams compliant with ATSC terrestrial broadcast, DBS (direct broadcast satellite), OpenCable, and standard definition DV (Digital Video) camcorders.

I think a logo program like this can be helpful to consumers. However, this particular logo does not appear to be very popular in the marketplace. The name appears in some product feature lists, but I do not recall seeing the logo anywhere.

Video On Demand

On Demand Entertainment, also known as Video on Demand, has long been predicted to be the next big thing in the delivery of entertainment. On Demand allows consumers to select programs whenever they want. In that respect, it appears to a high-value, consumer-oriented service. However, over the last ten years, nearly all On Demand services failed or performed well below expectations.

Now it appears that On Demand is back in several new forms. Once again, the analysts are producing graphs that show rapid adoption and profitability. So On Demand has gone from 10 years of proven failure to the next big success (maybe). What has changed?

In a way, nothing has changed. Cable has been betting on On Demand all along. They are hoping that a large success will grow out of it previous limited success. Also, the analysts have never stopped believing. Periodically, they are forced to push their forecasts out a couple more years.

The Telcos plan to launch VOD systems soon. The telco architecture allows singlecast: an individual signal for every TV set. Cable has limited singlecast capacity; it is optimized for broadcast. If On Demand turns out to be a significant revenue source, cable will be forced to transform its plant into an IP delivery system. It has made the first steps with HSD (High Speed Data).

Video On Demand comes in several forms:

PPV (Pay per view). This is a scheduled program than requires payment.

NVOD (Near video on demand). The program is played on multiple channels, each staggered in time.

VOD. The user determines the starting time, and may have pause, rewind, and other controls.

SVOD (Subscription video on demand). Same as VOD, except that there is a monthly subscription fee instead of a per program charge.

FVOD (Free video on demand). There is no additional per program charge.

PVOD (Push video on demand). Programs are downloaded onto a local DVR for later viewing. The requires less network bandwidth. It can be very effective with satellites.

Architecturally, there is a war between DVRs and head ends. VOD can have the same functionality as DVR. Should the programs be cached in the home? DVR adds cost to the STB, but it has also proven to be highly desirable. Keeping interactions closer to the user usually produces a better experience. The Studios don't want people to have copies on the content.

Everything on the Internet is On Demand. In the world of websites, there is no scheduled programming. VOD can make TV work more like the Internet. This could lead to the end of scheduled programming. Also, search engines may replace Interactive Program Guides. Programs will be accessed by URL, not by date, time, and channel.

Bird's eye view of DRM

I think that media DRM systems can be categorized into ten groups.

Link encryption

A link encryption DRM allows a program to be transferred between secure devices. HDCP sends programs to a display. DTCP transfers programs over over Firewire or IP. SSL is a link encryption system, but not a DRM system because it does not attempt to limit the rights of the receiver.


Macrovision makes products which interfere with the recording and playing of protected content. It is easily defeated, so it depends on the anti-circumvention restrictions in the DMCA for viability.

Copy Protection

CPPM/CPRM are to prevent the copying of disk media.


Proprietary systems are intended to work within the sphere of a single company's products. They product content within a product or a family of products. Examples include SVP, TiVoGuard, Windows Media, RealPlayer, and Apple Fairplay. Some of these are attempting to extend their sphere to include other company's products in order to establish themselves as a defacto standard. Windows Media is an example.


Some DRM systems are application specific. The most successful is the OMA's DRM, which protects ringtones sold and distributed thru cellphone networks.


Watermarking can be used to identify the intended receiver of a copy. This can make it possible to sue the person who allowed the work to be copied.

Watermarks can also be used to identify a work, its owner, and the rights of the holder.


Superdistribution allows people to make partially locked copies. If someone then pays to unlock a copy, some of the revenue can be shared with the people who made the copies. Superdistribution attempts to make every consumer a retailer.

Rights Language

A rights language is a formal notation for specifying rights. ODRL and MPEG-21 REL are examples. It is intended to provide a more flexible rights management system.


An interoperable system attempts to make other systems work together. Examples include Coral Consortium and AACS.


There are lots of DRM startup companies with products that will never find acceptance.

DRM Systems

The most significant DRM systems are the ones that were approved as part of the FCC's Broadcast Flag Rule. These are the only DRM systems to receive official government recognition. The approved list contains these categories only: Link encryption, Copy Protection, Proprietary. The FCC did not approve any systems in these categories: Annoyance, Application, Watermark, Superdistribution, Rights Language, Interoperable, Irrelevant.


Digital Transmission Content Protection.

Category: Link Encryption.

Owner: Digital Transmission Licensing Administrator, LLC (“DTLA”), which was founded by 5C (Hitachi, Intel, Matsushita, Sony, and Toshiba).

This is the most successful DRM technology so far. It was designed originally for Firewire. It has been adapted to IP and 802.11. Generally, consumers are not aware of it. It requires that the receiver be an approved device.


High Bandwidth Digital Content Protection.

Category: Link Encryption.

Owner: Digital Content Protection, LLC (Intel).

This is used with DVI and HDMI.


TiVoGuard Digital Output Protection Technology.

Category: Proprietary.

Owner: TiVo.

TiVoGuard allows for using the Internet for sharing programs between owners of TiVo DVRs. TiVoGuard restricts the number of times that a program can be copied, which meets the FCC's requirement of preventing unlimited copying.

MPAA is violently opposed to TiVoGuard. MPAA has been asserting that all copying of programs over the Internet is dangerous, illegal, and immoral. It is trying to force the FCC to revoke TiVoGuard's certification. The FCC voted 5-0 in favor of TiVoGuard, so it is unlikely that MPAA will be successful in getting the commision to change.


Content Protection Recordable Media for Video Content.

Category: Copy Protection.

Owner: 4C Entity, LLC (IBM, Intel, Matsushita, and Toshiba).

CPRM is a encryption scheme for recordable media, including DVD-R, DVD-RW, SD Memory Cards, Secure CompactFlash and Microdrive media. Programs recorded on a CPRM recorder can only be played back on an approved CPRM player. Copies are keyed to each individual disk or medium, so in theory it is not possible to make further copies. CPRM will be used in systems that allow users to make their own DVDs, which will reduce the cost of manufacturing and distribution for publishers.


Vidi Recordable DVD Protection System.

Category: Copy Protection.

Owner: Philips and HP.

The name of the system has been changed to VCPS (Video Content Protection System). It is similar to CPRM. It allows the making of an uncopyable DVD+RW from a programming source.


MagicGate Type-R for Secure Video Recording.

Category: Proprietary.

Owner: Sony.

MagicGate is Sony's proprietary DRM for exchanging content with Sony devices, such as Hi-MD recordable discs and Memory Stick PRO.



Category: Proprietary.

Owner: JVC.

D-VHS has a Copy Generation Management System feature which can restrict the number of copies allowed.

Windows Media

Windows Media Digital Rights Management Technology.

Category: Proprietary.

Owner: Microsoft.

This is the DRM system that makes the least sense to me, and is also the most dangerous. It is intended to restrict the ability of a PC user to copy content that is stored on or played through a PC or Windows Media device. Given the famous insecurity of Microsoft's products, it seems unlikely that Microsoft can keep the promises that it is making to Hollywood about protecting their content.

Microsoft is working very aggressively to make Windows Media into an industry standard. Its original intentions were to control the world's digital media formats and to charge a Microsoft Tax on all media. I think its current strategy is more defensive: If Windows Media DRM is required of all PC media players, then competitive systems such as Linux are blocked from the home market.


Helix DRM Trusted Recorder.

Category: Proprietary.

Owner: RealNetworks.

RealNetworks is competing directly with Microsoft. They share the same inherent security weaknesses as Microsoft when in a Windows environment.



Category: Proprietary.

Owner: Thomson.

SmartRight is a hardware-based DRM system using smart cards to implement a Personal Private Network. It is more credible than software-based systems like Windows Media and Helix. The smart cards control access and usage of media within the approved devices.


Logitech is a manufacturer of computer mice. This year they bought Intrigue Technologies for its Harmony Remote Control product. It is a universal, task-oriented remote control.

To use it, you must first configure it with a website. You identify the components in your video system (TV, VCR, DVD player, stereo, STB, etc.) by manufacturer and model number. You give information about how they are linked together in order to perform specific tasks. You then plug the remote into the computer USB port. It receives IR codes and macros.

It is most effective at managing complicated video systems in which it is necessary to control multiple devices at once. For example, many systems are put together in RF chains, and it is necessary to set all of the downstream devices to channel 3 in order to watch a DVD. In such configurations, Harmony can be extremely friendly.

I think that it will be obsolete in digital systems, where integration will ultimately be at the program level, not at the device level. I want to watch a program that might be on the DVR, or at the head end VOD library, or on the Internet, or on another DVR in another room. I want the system to find it for me. IR device codes are at too low a level to do that.


ConnectedTV is a company founded by David Levitt (who was at the MIT Media Lab). They have a program-oriented remote control. Their product is software that runs in a Palm organizer.

Most of the other smart remote control systems limit most interactions to four arrow buttons and a click. ConnectedTV instead makes very good use of the Palm, but can also be used effectively with one hand.

Set up is much more difficult than with the Harmony. ConnectedTV does not have a database of IR devices, so you must program the device codes yourself. You train it by having it observe your other remote controls, and by specifying channel changing conventions.

It displays program listings. It is good at browsing the listings. You can tune a program by tapping on its listing.

It may be the best way of accessing TV in realtime. I think it is irrelevant in a DVR world, because with a DVR you watch what you want, not what is on. If ConnectedTV were fully integrated with the DVR, then it could be the world's best remote control. Since it is a software product, this is most likely possible. It might also be possible to port ConnectedTV to a lower cost device, with buttons and features that make it a better remote control.

TiVo has USB ports on it. If those ports could be used to sync with a remote, and if it would accept programming commands from the remote, then it would be a very nice thing.