SG71930A1 - Pay broadcasting system with enchanced security against illegal access to a down loaded program in a subscriber terminal - Google Patents
Pay broadcasting system with enchanced security against illegal access to a down loaded program in a subscriber terminalInfo
- Publication number
- SG71930A1 SG71930A1 SG1999003148A SG1999003148A SG71930A1 SG 71930 A1 SG71930 A1 SG 71930A1 SG 1999003148 A SG1999003148 A SG 1999003148A SG 1999003148 A SG1999003148 A SG 1999003148A SG 71930 A1 SG71930 A1 SG 71930A1
- Authority
- SG
- Singapore
- Prior art keywords
- enchanced
- subscriber terminal
- broadcasting system
- security against
- illegal access
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client
- H04N21/63—Control signaling related to video distribution between client, server and network components; Network processes for video distribution between server and clients or between remote clients, e.g. transmitting basic layer and enhancement layers over different transmission paths, setting up a peer-to-peer communication via Internet between remote STB's; Communication protocols; Addressing
- H04N21/633—Control signals issued by server directed to the network components or client
- H04N21/6332—Control signals issued by server directed to the network components or client directed to client
- H04N21/6334—Control signals issued by server directed to the network components or client directed to client for authorisation, e.g. by transmitting a key
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
- H04H60/09—Arrangements for device control with a direct linkage to broadcast information or to broadcast space-time; Arrangements for control of broadcast-related services
- H04H60/14—Arrangements for conditional access to broadcast information or to broadcast-related services
- H04H60/23—Arrangements for conditional access to broadcast information or to broadcast-related services using cryptography, e.g. encryption, authentication, key distribution
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H60/00—Arrangements for broadcast applications with a direct linking to broadcast information or broadcast space-time; Broadcast-related systems
- H04H60/09—Arrangements for device control with a direct linkage to broadcast information or to broadcast space-time; Arrangements for control of broadcast-related services
- H04H60/14—Arrangements for conditional access to broadcast information or to broadcast-related services
- H04H60/15—Arrangements for conditional access to broadcast information or to broadcast-related services on receiving information
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/234—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs
- H04N21/2347—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs involving video stream encryption
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
- H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
- H04N21/433—Content storage operation, e.g. storage operation in response to a pause request, caching operations
- H04N21/4334—Recording operations
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
- H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
- H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs
- H04N21/4405—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs involving video stream decryption
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client
- H04N21/63—Control signaling related to video distribution between client, server and network components; Network processes for video distribution between server and clients or between remote clients, e.g. transmitting basic layer and enhancement layers over different transmission paths, setting up a peer-to-peer communication via Internet between remote STB's; Communication protocols; Addressing
- H04N21/633—Control signals issued by server directed to the network components or client
- H04N21/6332—Control signals issued by server directed to the network components or client directed to client
- H04N21/6334—Control signals issued by server directed to the network components or client directed to client for authorisation, e.g. by transmitting a key
- H04N21/63345—Control signals issued by server directed to the network components or client directed to client for authorisation, e.g. by transmitting a key by transmitting keys
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/76—Television signal recording
- H04N5/91—Television signal processing therefor
- H04N5/913—Television signal processing therefor for scrambling ; for copy protection
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N7/00—Television systems
- H04N7/16—Analogue secrecy systems; Analogue subscription systems
- H04N7/167—Systems rendering the television signal unintelligible and subsequently intelligible
- H04N7/1675—Providing digital key or authorisation information for generation or regeneration of the scrambling sequence
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/76—Television signal recording
- H04N5/91—Television signal processing therefor
- H04N5/913—Television signal processing therefor for scrambling ; for copy protection
- H04N2005/91357—Television signal processing therefor for scrambling ; for copy protection by modifying the video signal
- H04N2005/91364—Television signal processing therefor for scrambling ; for copy protection by modifying the video signal the video signal being scrambled
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Multimedia (AREA)
- Computer Security & Cryptography (AREA)
- Computer Networks & Wireless Communication (AREA)
- Theoretical Computer Science (AREA)
- Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
- Storage Device Security (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20109098A JP3565715B2 (ja) | 1998-07-02 | 1998-07-02 | 放送システムと放送送受信装置 |
Publications (1)
Publication Number | Publication Date |
---|---|
SG71930A1 true SG71930A1 (en) | 2000-04-18 |
Family
ID=16435238
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
SG1999003148A SG71930A1 (en) | 1998-07-02 | 1999-07-02 | Pay broadcasting system with enchanced security against illegal access to a down loaded program in a subscriber terminal |
Country Status (8)
Country | Link |
---|---|
US (1) | US6714649B1 (de) |
EP (2) | EP1562378A1 (de) |
JP (1) | JP3565715B2 (de) |
KR (1) | KR100304806B1 (de) |
CN (1) | CN1144462C (de) |
AU (1) | AU741900B2 (de) |
SG (1) | SG71930A1 (de) |
TW (1) | TW416246B (de) |
Families Citing this family (55)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2001016776A1 (fr) * | 1999-08-27 | 2001-03-08 | Sony Corporation | Systeme de transmission d'informations, emetteur et recepteur, procede de transmission d'informations, procede de reception d'informations |
US7110542B1 (en) * | 1999-12-30 | 2006-09-19 | Intel Corporation | Protecting audio/video content during storage and playback on a processor-based system |
DE60133359T2 (de) * | 2000-06-21 | 2009-04-02 | Sony Corp. | Informationsverarbeitungsvorrichtung und Informationsverarbeitungsverfahren |
JP4620878B2 (ja) * | 2001-01-22 | 2011-01-26 | 株式会社日立製作所 | 放送方法及び放送受信装置 |
PL358713A1 (en) * | 2001-01-31 | 2004-08-09 | Ntt Docomo, Inc. | System for delivering program to storage module of mobile terminal |
US20020101990A1 (en) * | 2001-02-01 | 2002-08-01 | Harumi Morino | Data receiving apparatus and data reproducing apparatus |
AU1547402A (en) | 2001-02-09 | 2002-08-15 | Sony Corporation | Information processing method/apparatus and program |
US7302571B2 (en) * | 2001-04-12 | 2007-11-27 | The Regents Of The University Of Michigan | Method and system to maintain portable computer data secure and authentication token for use therein |
JP4174191B2 (ja) * | 2001-04-19 | 2008-10-29 | 日本電気株式会社 | 著作権保護システム及びその方法 |
JP2002319933A (ja) * | 2001-04-20 | 2002-10-31 | Sony Corp | 通信システム |
FR2824212A1 (fr) * | 2001-04-25 | 2002-10-31 | Thomson Licensing Sa | Procede de gestion d'une cle symetrique dans un reseau de communication et dispositifs pour la mise en oeuvre |
KR20020083812A (ko) * | 2001-04-30 | 2002-11-04 | 주식회사 시큐어넥서스 | 브로드캐스팅 방식의 컨텐츠 서비스의 보안시스템 및 그의제어방법 |
JP2003050745A (ja) * | 2001-08-07 | 2003-02-21 | Sony Corp | 情報処理装置、および情報処理方法、並びにコンピュータ・プログラム |
JP3841337B2 (ja) * | 2001-10-03 | 2006-11-01 | 日本放送協会 | コンテンツ送信装置、コンテンツ受信装置およびコンテンツ送信プログラム、コンテンツ受信プログラム |
WO2003036857A1 (en) | 2001-10-24 | 2003-05-01 | Nokia Corporation | Ciphering as a part of the multicast cencept |
JP2003152698A (ja) * | 2001-11-15 | 2003-05-23 | Nippon Hoso Kyokai <Nhk> | コンテンツ利用制御送信方法、コンテンツ利用制御受信方法およびコンテンツ利用制御送信装置、コンテンツ利用制御受信装置ならびにコンテンツ利用制御送信プログラム、コンテンツ利用制御受信プログラム |
JP4157709B2 (ja) | 2002-01-31 | 2008-10-01 | 富士通株式会社 | アクセス制御方法及び記憶装置 |
FR2836609A1 (fr) * | 2002-02-25 | 2003-08-29 | Thomson Licensing Sa | Procede de traitement de donnees chiffrees pour un premier domaine et recues dans un reseau appartenant a un second domaine |
US7299364B2 (en) * | 2002-04-09 | 2007-11-20 | The Regents Of The University Of Michigan | Method and system to maintain application data secure and authentication token for use therein |
US7885896B2 (en) | 2002-07-09 | 2011-02-08 | Avaya Inc. | Method for authorizing a substitute software license server |
US8041642B2 (en) | 2002-07-10 | 2011-10-18 | Avaya Inc. | Predictive software license balancing |
US7707116B2 (en) | 2002-08-30 | 2010-04-27 | Avaya Inc. | Flexible license file feature controls |
US7966520B2 (en) | 2002-08-30 | 2011-06-21 | Avaya Inc. | Software licensing for spare processors |
KR100497435B1 (ko) * | 2002-08-30 | 2005-06-23 | (주)비웨이 | 이동 환경에서의 방송을 통한 정보 서비스방법 |
US7681245B2 (en) | 2002-08-30 | 2010-03-16 | Avaya Inc. | Remote feature activator feature extraction |
CN1703894A (zh) * | 2002-10-30 | 2005-11-30 | 汤姆森许可贸易公司 | 用于在数字网络中更新对称密钥的简化方法 |
US7890997B2 (en) | 2002-12-26 | 2011-02-15 | Avaya Inc. | Remote feature activation authentication file system |
KR100987231B1 (ko) * | 2003-07-16 | 2010-10-12 | 삼성전자주식회사 | 이동통신 시스템에서 방송 서비스 과금 방법 |
WO2005013550A1 (ja) * | 2003-08-05 | 2005-02-10 | Matsushita Electric Industrial Co., Ltd. | 著作権保護システム |
US9461825B2 (en) * | 2004-01-30 | 2016-10-04 | Broadcom Corporation | Method and system for preventing revocation denial of service attacks |
US20050172132A1 (en) | 2004-01-30 | 2005-08-04 | Chen Sherman (. | Secure key authentication and ladder system |
EP1575292A1 (de) * | 2004-03-10 | 2005-09-14 | Nagracard S.A. | Verfahren zur Sicherung von übertragenem verschlüsseltem Inhalt |
CN100384251C (zh) * | 2004-08-02 | 2008-04-23 | 华为技术有限公司 | 用户授权方法及其授权系统 |
US20060031873A1 (en) | 2004-08-09 | 2006-02-09 | Comcast Cable Holdings, Llc | System and method for reduced hierarchy key management |
US7707405B1 (en) | 2004-09-21 | 2010-04-27 | Avaya Inc. | Secure installation activation |
US8229858B1 (en) | 2004-09-30 | 2012-07-24 | Avaya Inc. | Generation of enterprise-wide licenses in a customer environment |
US7747851B1 (en) | 2004-09-30 | 2010-06-29 | Avaya Inc. | Certificate distribution via license files |
US8160244B2 (en) * | 2004-10-01 | 2012-04-17 | Broadcom Corporation | Stateless hardware security module |
JP4741318B2 (ja) * | 2005-08-23 | 2011-08-03 | 日本放送協会 | コンテンツ変換装置、コンテンツ変換方法及びコンテンツ変換プログラム |
US7814023B1 (en) * | 2005-09-08 | 2010-10-12 | Avaya Inc. | Secure download manager |
US7953846B1 (en) | 2005-11-15 | 2011-05-31 | At&T Intellectual Property Ii, Lp | Internet security updates via mobile phone videos |
US7926107B2 (en) * | 2005-11-15 | 2011-04-12 | At&T Intellectual Property Ii, Lp | Internet security news network |
JP4542518B2 (ja) * | 2006-03-13 | 2010-09-15 | 日本放送協会 | コンテンツ利用制御送信装置、コンテンツ利用制御受信装置、コンテンツ利用制御システム、コンテンツ利用制御送信プログラムおよびコンテンツ利用制御受信プログラム |
FR2902585B1 (fr) * | 2006-06-14 | 2008-09-26 | Viaccess Sa | Procedes de diffusion et de reception d'un programme multimedia embrouille, tete de reseau, terminal, recepteur et processeur de securite pour ces procedes |
KR100781531B1 (ko) * | 2006-09-19 | 2007-12-03 | 삼성전자주식회사 | 컨텐츠 서비스 제공 방법 및 장치 |
CN101150395B (zh) * | 2006-09-22 | 2010-05-12 | 中国科学院声学研究所 | 一种加密授权管理系统的双重分组的四层加密方法 |
WO2008074534A1 (en) * | 2006-12-21 | 2008-06-26 | International Business Machines Corporation | Key distribution for securing broadcast transmission to groups of users in wireless networks |
CN101026451B (zh) * | 2007-02-02 | 2010-09-29 | 清华大学 | 条件接收系统中基于产品和用户分别分组的密钥分配方法 |
JP2008271564A (ja) * | 2008-04-25 | 2008-11-06 | Fujitsu Ltd | ライセンスのオフライン環境下における送信流通システム及び送信流通方法 |
JP5167079B2 (ja) * | 2008-11-13 | 2013-03-21 | キヤノン株式会社 | 受信装置及びその制御方法 |
JP5255499B2 (ja) * | 2009-03-30 | 2013-08-07 | 株式会社エヌ・ティ・ティ・ドコモ | 鍵情報管理方法、コンテンツ送信方法、鍵情報管理装置、ライセンス管理装置、コンテンツ送信システム、及び端末装置 |
JP4967005B2 (ja) * | 2009-09-24 | 2012-07-04 | 日本放送協会 | コンテンツ受信装置、コンテンツ受信プログラムおよび限定受信システム |
JP7057675B2 (ja) * | 2018-01-09 | 2022-04-20 | ラピスセミコンダクタ株式会社 | 半導体装置及び暗号鍵の生成方法 |
KR102608667B1 (ko) * | 2018-12-05 | 2023-12-01 | 삼성전자주식회사 | 전자장치, 서버 및 그 제어방법 |
CN110890968B (zh) * | 2019-10-24 | 2022-08-23 | 成都卫士通信息产业股份有限公司 | 一种即时通信方法、装置、设备及计算机可读存储介质 |
Family Cites Families (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU562395B2 (en) | 1981-09-10 | 1987-06-11 | Sony Corporation | Subscription television system |
US4658292A (en) * | 1982-04-30 | 1987-04-14 | Nec Corporation | Enciphering key distribution system for subscription TV broadcast or catv system |
US4613901A (en) | 1983-05-27 | 1986-09-23 | M/A-Com Linkabit, Inc. | Signal encryption and distribution system for controlling scrambling and selective remote descrambling of television signals |
US4712238A (en) * | 1984-06-08 | 1987-12-08 | M/A-Com Government Systems, Inc. | Selective-subscription descrambling |
CA1244090A (en) | 1984-10-26 | 1988-11-01 | General Instrument Corporation | Cryptographic system for direct broadcast satellite network |
US4887296A (en) | 1984-10-26 | 1989-12-12 | Ricoh Co., Ltd. | Cryptographic system for direct broadcast satellite system |
US4799061A (en) | 1985-11-18 | 1989-01-17 | International Business Machines Corporation | Secure component authentication system |
US4864615A (en) | 1988-05-27 | 1989-09-05 | General Instrument Corporation | Reproduction of secure keys by using distributed key generation data |
FR2715256B1 (fr) | 1994-01-19 | 1996-02-16 | France Telecom | Procédés d'émission et de réception de programmes à accès conditionnel gérés par un même opérateur. |
JPH07231424A (ja) * | 1994-02-18 | 1995-08-29 | Hitachi Ltd | 記録再生方式およびその装置 |
JPH07245605A (ja) * | 1994-03-03 | 1995-09-19 | Fujitsu Ltd | 暗号化情報中継装置とそれに接続される加入者端末装置ならびに暗号通信方法 |
JPH0832530A (ja) | 1994-07-15 | 1996-02-02 | Sony Corp | データ放送システムおよびデータ受信装置 |
DE69532153T2 (de) * | 1994-09-30 | 2004-09-02 | Mitsubishi Corp. | Datenurheberrechtsverwaltungssystem |
DE69535013T2 (de) * | 1994-10-27 | 2006-12-28 | Intarsia Software LLC, Las Vegas | Urheberrechtsdatenverwaltungssystem |
JPH08149449A (ja) | 1994-11-18 | 1996-06-07 | Hitachi Ltd | デジタル信号蓄積伝送装置 |
JPH08335040A (ja) * | 1995-06-02 | 1996-12-17 | Fujitsu Ltd | 暗号化処理方式 |
US6067121A (en) * | 1995-06-07 | 2000-05-23 | Kabushiki Kaisha Toshiba | Scrambled broadcast system |
US5754651A (en) | 1996-05-31 | 1998-05-19 | Thomson Consumer Electronics, Inc. | Processing and storage of digital data and program specific information |
JPH1011894A (ja) | 1996-06-21 | 1998-01-16 | Toshiba Corp | 有料スクランブル放送の受信記録再生システム |
JP3093678B2 (ja) | 1996-06-28 | 2000-10-03 | 株式会社東芝 | 暗号化方法、復号方法、記録再生装置、復号装置、復号化ユニット装置及び記録媒体の製造方法 |
FR2751817B1 (fr) | 1996-07-29 | 1998-09-11 | Thomson Multimedia Sa | Systeme a acces conditionnel utilisant des messages a cles de chiffrement multiples |
JPH11346214A (ja) * | 1998-06-02 | 1999-12-14 | Nec Corp | 同報配信システム |
-
1998
- 1998-07-02 JP JP20109098A patent/JP3565715B2/ja not_active Expired - Fee Related
-
1999
- 1999-07-01 AU AU37949/99A patent/AU741900B2/en not_active Ceased
- 1999-07-01 US US09/345,829 patent/US6714649B1/en not_active Expired - Lifetime
- 1999-07-01 TW TW088111202A patent/TW416246B/zh not_active IP Right Cessation
- 1999-07-02 KR KR1019990026613A patent/KR100304806B1/ko not_active IP Right Cessation
- 1999-07-02 CN CNB99110174XA patent/CN1144462C/zh not_active Expired - Fee Related
- 1999-07-02 EP EP05009115A patent/EP1562378A1/de not_active Withdrawn
- 1999-07-02 SG SG1999003148A patent/SG71930A1/en unknown
- 1999-07-02 EP EP99112808A patent/EP0969667A3/de not_active Withdrawn
Also Published As
Publication number | Publication date |
---|---|
CN1144462C (zh) | 2004-03-31 |
JP2000023137A (ja) | 2000-01-21 |
TW416246B (en) | 2000-12-21 |
JP3565715B2 (ja) | 2004-09-15 |
EP0969667A2 (de) | 2000-01-05 |
EP0969667A3 (de) | 2004-01-07 |
AU741900B2 (en) | 2001-12-13 |
AU3794999A (en) | 2000-01-20 |
KR100304806B1 (ko) | 2001-11-01 |
KR20000011441A (ko) | 2000-02-25 |
EP1562378A1 (de) | 2005-08-10 |
CN1249621A (zh) | 2000-04-05 |
US6714649B1 (en) | 2004-03-30 |
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