WO2006000029A1 - Systeme de diffusion de contenu et lecteur - Google Patents

Systeme de diffusion de contenu et lecteur Download PDF

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Publication number
WO2006000029A1
WO2006000029A1 PCT/AU2005/000911 AU2005000911W WO2006000029A1 WO 2006000029 A1 WO2006000029 A1 WO 2006000029A1 AU 2005000911 W AU2005000911 W AU 2005000911W WO 2006000029 A1 WO2006000029 A1 WO 2006000029A1
Authority
WO
WIPO (PCT)
Prior art keywords
content
player
code
content item
seed
Prior art date
Application number
PCT/AU2005/000911
Other languages
English (en)
Inventor
Stephen Spicer
Timothy Charles Hoad
Original Assignee
Telstra Corporation Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU2004903438A external-priority patent/AU2004903438A0/en
Application filed by Telstra Corporation Limited filed Critical Telstra Corporation Limited
Publication of WO2006000029A1 publication Critical patent/WO2006000029A1/fr

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F21/10—Protecting distributed programs or content, e.g. vending or licensing of copyrighted material ; Digital rights management [DRM]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
    • H04L9/0861—Generation of secret information including derivation or calculation of cryptographic keys or passwords
    • H04L9/0869—Generation of secret information including derivation or calculation of cryptographic keys or passwords involving random numbers or seeds
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L2209/00—Additional information or applications relating to cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
    • H04L2209/60—Digital content management, e.g. content distribution
    • H04L2209/603—Digital right managament [DRM]

Definitions

  • the present invention relates to a content player and a content delivery system.
  • DRM Digital Rights Management
  • a problem inherent in the existing content delivery systems and players is that the players can be hacked or reverse engineered to remove the DRM restrictions, or a player without DRM support can be used or developed to play all content files in the standard digital media delivery formats, such as MP3, AAC and MPEG-2. This problem has assisted the wide proliferation of unauthorised and pirated content distributed on the various peer to peer networks of the Internet.
  • a content delivery process including: generating a unique seed; accessing and adjusting a content item on the basis of the seed; compiling content player code on the basis of the seed; and transmitting the content item and the player code in response to a request for the content item.
  • the present invention also provides a content delivery system, including: a communications interface for connection to a communication network; a delivery control module for processing requests for content items from at least one client device connected to said network; an obfuscation module including a seed generator for generating a unique seed, a media adjuster for adjusting a requested content item on the basis of said seed, and a content player compiler for compiling source code of a content player on the basis of said seed to generate player code for the content item; and a packaging module for packaging said content item and said player code for transmission.
  • the present invention also provides a content player, including: a shell for generating a user interface, accessing unique hardware profile data from a client device and transmitting said hardware profile data to a content delivery system; and a media player including a decoder for generating a key to decrypt a content item bound to said media player, using said hardware profile data.
  • the present invention also provides a content player uniquely bound to a content item.
  • the present invention also provides a content player compiled using a unique seed so as to read only content delivered using said unique seed.
  • Figure 1 is a block diagram of a preferred embodiment of a content delivery system communicating with a client device
  • Figure 2 is a block diagram of delivery components of the system
  • Figure 3 is a block diagram of components of a preferred embodiment of a content player
  • Figure 4 is a flow diagram of steps performed by the content delivery system
  • Figure 5 is a flow diagram of steps performed by the content player.
  • a content delivery system 100 includes a content server 110, with a database server 120, that communicates with a client device 130 using a communications network 140.
  • the server 110 has a communications interface 150 for connection to the network 140, a delivery control module 160, a content preparation module 182, an obfuscation module 102, an encryption module 184 and a packaging module 186.
  • the modules 180 to 186 operate to prepare for delivery a player 190 and a content item 192 bound to the player for the client device 130.
  • the content items include digital media stored in source files held by the database 120, or another database accessible over the network 140 by the server 110.
  • the files represent media or multimedia content, eg text, graphics, audio and/or video.
  • the communications network 140 is a public communications network, such as the Internet, and the client device 130 is hereinafter described as a personal computer (http://www.ibm.com) running an operating system (OS) 194, such as Linux or Windows XP, that allows the establishment of TCP/IP connections over the network 140, and runs a browser 196, such as Internet Explorer or Safari.
  • the server 110 is also described as having a communications interface 150 that includes a web server 150, such as Apache (http://www.apache.org), allowing the server 110 to communicate using TCP/IP based protocols such as HTTP.
  • the server 110 could be a different form of client server, such as a WAP server
  • the client device 130 could be a different form of computer device, such as a mobile phone or PDA.
  • the components 160 to 186 can provided by software, in languages such as Java (htt ⁇ ://www.java.sun.com), Perl (http://www.perl.org), C++ and HTML
  • the database server 120 can be provided using software, such as MySQL4 (http://www.mysql.org), which all run on an operating system, such as the Linux OS (http://www.linux.org), on a standard computer 112, such as a PC server (http://www.ibm.com).
  • the software and hardware components of the server 110 can also be placed on a number of distributed computers connected by the communications network 140, and the processes executed by the components 160 to 186 can also be executed at least in part by dedicated hardware circuits, eg ASICs or FPGAs, which may be required to improve the speed of the processes.
  • dedicated hardware circuits eg ASICs or FPGAs
  • the content delivery server 110 performs a content delivery process, as shown generally in Figure 4.
  • the control module 160 includes web pages that can be accessed by the client device 130, and which allow the client 130 to select and submit a request for a particular item of content offered on the pages (step 402).
  • the content may also be offered on other web sites, not hosted by the server 110, and the server 110 can handle HTTP requests for the download of specific content items.
  • the user of the client 130 is able to access the pages of a content distribution web site and select from a number of content titles, the particular content file that is desired. A particular movie may be located, and the user is then able to select download of the file selecting a 'buy' download link on the site and sending the corresponding HTTP request to the server 110.
  • step 404 an applet of the control module 160 is served by the server 110 to run on the client 130 and determine if a shell 302 of the player 190 has been installed on the client 130.
  • the shell 302 includes a plugin for the browser 196, a user interface, code for supporting different skins of the interface, code for content management (eg playlists and libraries), and code to collect hardware profile data from the client device 130.
  • the content libraries include code to handle playlists and content management.
  • step 406 at which the user is presented with a HTML message rendered by the browser 196 advising that the shell must be downloaded in order to access the content.
  • the shell is a small program, about 300k to 800k, that needs to be downloaded and stored on the client device before operation proceeds to step 408. Once the shell has been properly installed, the user must again select the download link so that the shell can be detected at step 404.
  • purchase pages are presented to the user if it is necessary to purchase the content item.
  • the pages allow the entry of credit card details and notification of payment.
  • the control module 160 generates a unique user identification data (UID) to identify the user.
  • UID is stored with information identifying the content item, derived from the download link, in the database 120.
  • Approval of download of the content also causes the control module 160 to instruct the shell 302 to commence execution (step 502).
  • the shell 302 is transparently informed of the universal resource locator (URL) specifying the content and its location for use by the server 110.
  • the shell 302 of the player 190 stores the URL and the UID, which is sent to the client device 130 when generated by the content server 110 (502).
  • the shell 302 accesses the URL to request the content and accesses unique hardware profile data of the client device 130 that specifically identifies the device 130.
  • the unique profile data can be selected from one or a combination of microprocessor characteristics, amount of memory, hard disk model, serial number, network card MAC address, OS version, video and sound card type and/or other hardware identification data of the device 130.
  • the profile data may also include data which identifies the user, such as username and email address.
  • the unique hardware profile data is extracted and forwarded to the server 110 (504), for storage in the database 120 against the user's UID, with URL requesting the content (409).
  • the shell 302 then waits for the content to be downloaded (506).
  • the control module 160 On receiving the request (409) and determining that the content has been paid for, again based on the UID, the control module 160 causes access of the respective media file for the content (step 410).
  • the media file for the content item is in a format that needs to prepared and obfuscated for delivery. Alternatively, the media file can be stored in an obfuscated format with a unique customised player ready for delivery.
  • the preparation module 180 has a source access module 202 to access source files of uncompressed media from the database 120 or other databases, and compress the selected file or files using a media encoder, such as an MPEG-2, or an MPEG-4 encoder.
  • the accessed media source file may be any unencrypted digital content, such as capture from a digital video camera, scanned prints or documents, and/or an audio recording.
  • the preparation module 180 also has a player source module to access media player source code for the player 190.
  • the media player source code is selected from a library of interchangeable modules to produce an entity that is able to render the selected content.
  • the preparation module also has a rights definition access module 208 to access rights definition data for the selected content item.
  • This rights definition data specifies how the content can be played, such as once only or an unlimited number of times in one week. It is also able to limit the content to a particular client device 130 or may require payment each time the content is accessed by the player 190.
  • the rights definition data is expressed in a rights expression language, such as XrML or ODRL.
  • the rights expression language is combined with DRM source code accessed by a DRM source access module 210 to produce combined DRM source code for the player 190, which is incorporated in the media player code 304.
  • the compressed media file, the media player source code and the DRM source code are accessed by the obfuscation module 182 which includes a seed generator 212, a media shuffler 214 and the player compiler 216.
  • the seed generator 212 generates seed data, such as that representing a pseudo-random number, so as to provide a seed for use by the media shuffler 214 and a player compiler 216.
  • the player compiler 216 produces a compiled version of the player source code and DRM source code using the seed so as to produce a unique customised media player 304.
  • the media shuffler 214 uses the seed to adjust the compressed media data so as to produce a unique obfuscated media file that can only be played by the unique player 190.
  • the media shuffler 214 rearranges the compressed media file or alters it so that the compressed data remains intact, but the structure or meaning of the data is hidden from standard players. This is achieved by stream structure manipulation, such as altering the field sizes, rearranging fields or modifying start codes.
  • the start code used for a video frame could be made variable, and dependent on, for example, the content of the previous frame.
  • the media can also be shuffled or adjusted by using VLC table substitution and coefficient shuffling.
  • the seed generator 212 may simply generate a pseudo-random number, or can be tied to the form of the content or the particular content file itself that is to be shuffled.
  • the content file may provide a seed to generate the next seed for the media shuffler 214 and the player compiler 216.
  • the compiler 216 is a standard C++ or C# compiler that uses pre ⁇ processing instructions controlled by the seed to generate the unique player.
  • the player 190 is unique in that the media player code 304 is adjusted so it is able to read, decode and render the obfuscated content 192.
  • the compiler 216 can dynamically generate the unique source code, with reference to the seed, using the code provided by the player source code access module 206 as a base, and then pass this dynamic generated code to a standard compiler.
  • the adjustment process employed by the media shuffler 214 is controlled based on the seed and the code 304 of the player 190 is adjusted by the compiler 216 also based on the same seed, so it is able to decompress and render the obfuscated media file 192, thereby binding the two. Binding the player 190 to one media file 192 in this manner is significant because if the DRM code of the player is cracked and rendered redundant, the player is only useful for playing one media file and cannot be used for generally playing other compressed media files delivered by the system 110.
  • the encryption process implemented by the encryption module 184 as described below, also prevents the unique player 190 and the bound media file 192 being moved between client devices 130 without approval.
  • the encryption module 184 receives the obfuscated media file and the unique media player, and includes an encryption engine 218 for performing (420) a number of standard encryption algorithms that use relatively strong encryption, eg 128 bit encryption.
  • the encryption module 104 also includes an encryption key generator 220 for generating a number of keys that are used by the algorithms executed by the encryption engine 218. In generating the keys (420), the encryption key generator 220 first generates a random encryption key K which is used to encrypt the obfuscated media file. The key generator 220 then uses the unique hardware profile data stored against the user's UID to generate a first unique hardware identifier (HID), and a second unique hardware identifier (HID 2 ) using similar but different generation processes.
  • HID unique hardware identifier
  • HID 2 second unique hardware identifier
  • the encryption key generator also receives a hash (PH) of the media player code 304 produced by the player compiler 216.
  • the hash value (PH) together with the encryption key K, the HID and the UID, are used by the key generator 220 to produce a device decryption key (DK).
  • the key DK is produced by applying an XOR to the combined K, PH, HID and UID.
  • the code 304 of the customised media player is encrypted using the HID 2 .
  • the two encrypted components 192 and 304 and the device key DK are passed to the packaging module 186.
  • the manner in which the device key is generated makes DK unique to a particular user, and more importantly to a particular device, such that the content can only be played with a specific client device 130, as described below.
  • Also generating DK using the PH means the content can only be decrypted if the PH can be generated from the player code. Accordingly hacking of the player code will prevent decryption of the content.
  • the packaging module 186 receives the encrypted components, being the media player code and the media file, and uses a packager module 230 to wrap them in a self decrypting executable archive that is sent by the control module 160 to the client device 130 (440).
  • the packager 230 includes in the archive the player code 304 that operates with the shell 302, unpacker code 306 for unpacking the self extracting archive, the device key DK, and the encrypted and obfuscated content 192.
  • the player code 304 includes a decoder (or codec), to operate with the shell 302, code to calculate the player hash, code to generate the HID, and code to reconstitute the decryption key K using the DK, the generated PH, the generated HID and the UID stored by the shell 302.
  • the unpacker 306 in addition to including the code for unpacking the archive, includes code for generating the HID 2 and using this code to decrypt the player code 304 using the HID 2 .
  • the archive file is similar to a ZIP or TAR file, but a different extension is used, eg ".dmp".
  • the media player code 304 and the content 192, together with the unpacker 306, are delivered each time content is delivered, whereas the shell 302 is only delivered once for first time users on a particular device 130.
  • the shell 302 Once the shell 302 has completed download of the self extracting file with the encrypted content, media player and device key DK (506) a request can be made using the shell 302 to play the content (508). On receiving a request to play the content, the shell 302 determines whether the media player code 304 of the player 190 and the content 192 needs to be unpacked and decrypted (520). If unpacking and decryption is required, the shell 302 launches the unpacker 306 (510). The unpacker 306 accesses the hardware profile data from the client device 130 and generates the HID 2 . This is used by the unpacker to decrypt the encrypted media player code 304.
  • the player code 304 will be correctly decrypted and is executed so as to generate a player hash PH and generate a HID, again based on the profile data accessed from the client device 130.
  • the media player code 304 accesses the device key and UID, and uses the generated PH and HID to generate a decryption key K.
  • the generated key K is used to decrypt the content file 192 and if successful (512) the content is played for the user on the device 130 (530).
  • the shell 302 If any of the decryption steps are unsuccessful (512), ie the media player code 304 is not able to run, or the content 192 cannot be properly played or decrypted, the shell 302 generates a notification message (514) for the user accordingly. For example, the user may have copied the media file or the packaged file to another client device, in which case either the downloaded shell 302 looks for absent media player code 304, the incorrect HID 2 is generated or the incorrect decryption key K is generated using the DK for the initial client device. The user is advised (514) that he does not have permission to access the content from the new device and is prompted to obtain permission from the server 110. This involves the shell 302 again requesting the content (504) and sending the hardware profile data for the new device.
  • the server 110 then proceeds through steps 402 to 440 to provide the player code and content for the new device, and this may or may not require an additional purchase.
  • the control module 160 may determine on the basis of the UID provided by the shell 302 that the requested content has already been purchased for another device, and simply causes generation and transmission of another device key DK for the new device (506), on receiving the hardware profile data (504). Based on the hardware profile data a HID 2 is generated for the new device and a new player encrypted by the HID 2 is also downloaded (506).
  • the primary target for share and trade of content, without authorisation, is compressed media files.
  • Clear uncompressed files are normally too large in size for sharing and download.
  • Clear uncompressed files also normally require re-encoding for play and rendering by media players.
  • Clear analog data is also less attractive because it needs to be recorded in a digital form and encoded for sharing.
  • the compressed media file 192 that the client device 130 receives is encrypted using a key that can only be obtained using data unique to the device 130 itself, and even if decrypted, is still shuffled or adjusted so that it can only be played by a player 190 that is unique and specific to that content.
  • the content item 192 is bound to a player 190 and a device 130.
  • the content may be further bound to the player 190 by compressing the content using a codec specific and unique to the customised player 190 and even shuffling the content file 192 amongst the code 304 for the player 304.

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  • Engineering & Computer Science (AREA)
  • Software Systems (AREA)
  • Theoretical Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • General Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Technology Law (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Storage Device Security (AREA)

Abstract

L'invention concerne un système de diffusion de contenu, qui comprend une interface de communication devant être connectée à un réseau de communication, un module de commande de diffusion pour traiter les demandes d'articles de contenu provenant d'au moins un dispositif client (130) connecté au réseau (140), un module d'obscurcissement (182), et un module d'emballage de module (186) pour emballer un article de contenu et un code de lecture en vue de la transmission. Le module d'obscurcissement (182) comprend un générateur de valeurs de départ (212) pour produire une valeur de départ unique; un dispositif de réglage de média (214) pour régler l'article de contenu demandé sur la base de la valeur de départ; et un compilateur de lecteur de contenu (216) pour compiler le code source de compilation d'un lecteur de contenu sur la base de la valeur de départ, et produire un code de lecteur pour l'article de contenu.
PCT/AU2005/000911 2004-06-23 2005-06-23 Systeme de diffusion de contenu et lecteur WO2006000029A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AU2004903438 2004-06-23
AU2004903438A AU2004903438A0 (en) 2004-06-23 Content delivery system and player

Publications (1)

Publication Number Publication Date
WO2006000029A1 true WO2006000029A1 (fr) 2006-01-05

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU2005/000911 WO2006000029A1 (fr) 2004-06-23 2005-06-23 Systeme de diffusion de contenu et lecteur

Country Status (1)

Country Link
WO (1) WO2006000029A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2927209A1 (fr) * 2008-02-05 2009-08-07 France Telecom Protection d'un contenu, notamment multimedia
EP2118806A1 (fr) * 2007-03-02 2009-11-18 Vividas Technologies PTY LTD Procédé, système, et produit logiciel pour transférer un contenu vers un dispositif distant
AU2016202276B2 (en) * 2007-03-02 2017-05-25 Vividas Technologies Pty Ltd Method, system and software product for transferring content to a remote device
EP3005207B1 (fr) * 2013-05-30 2020-09-30 JScrambler S.A. Mécanisme de commande d'exécution de contenu numérique

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WO1999012087A2 (fr) * 1997-09-05 1999-03-11 Librius, Inc. Systeme de transmission cryptographique et d'affichage de livres electroniques
WO2000058963A2 (fr) * 1999-03-26 2000-10-05 Liquid Audio, Inc. Securite anti-duplication pour lecteurs de musique portables
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WO2002001335A2 (fr) * 2000-06-27 2002-01-03 Microsoft Corporation Systeme et procede d'activation d'un dispositif de rendu dans une architecture multiniveau de gestion des droits
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WO1999012087A2 (fr) * 1997-09-05 1999-03-11 Librius, Inc. Systeme de transmission cryptographique et d'affichage de livres electroniques
WO2000058963A2 (fr) * 1999-03-26 2000-10-05 Liquid Audio, Inc. Securite anti-duplication pour lecteurs de musique portables
WO2000062232A1 (fr) * 1999-04-12 2000-10-19 Digital Media On Demand, Inc. (Dmod, Inc.) Systeme de commerce electronique sur
WO2001046786A1 (fr) * 1999-12-20 2001-06-28 Liquid Audio, Inc. Mecanisme de securite adaptable destine a empecher l'acces non autorise a des donnees numeriques
WO2002001335A2 (fr) * 2000-06-27 2002-01-03 Microsoft Corporation Systeme et procede d'activation d'un dispositif de rendu dans une architecture multiniveau de gestion des droits
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JP2004012866A (ja) * 2002-06-07 2004-01-15 Nippon Telegr & Teleph Corp <Ntt> コンテンツ配信方法、装置及びプログラム

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2118806A1 (fr) * 2007-03-02 2009-11-18 Vividas Technologies PTY LTD Procédé, système, et produit logiciel pour transférer un contenu vers un dispositif distant
EP2118806A4 (fr) * 2007-03-02 2013-08-21 Vividas Technologies Pty Ltd Procédé, système, et produit logiciel pour transférer un contenu vers un dispositif distant
US8931105B2 (en) 2007-03-02 2015-01-06 Vividas Technologies Pty. Ltd. Method, system and software product for transferring content to a remote device
AU2016202276B2 (en) * 2007-03-02 2017-05-25 Vividas Technologies Pty Ltd Method, system and software product for transferring content to a remote device
FR2927209A1 (fr) * 2008-02-05 2009-08-07 France Telecom Protection d'un contenu, notamment multimedia
EP3005207B1 (fr) * 2013-05-30 2020-09-30 JScrambler S.A. Mécanisme de commande d'exécution de contenu numérique

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