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1、 CEA Standard NRSS Copy Protection Systems CEA-796-A October 2005 Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from
2、 IHS -,-,- NOTICE CEA Standards, Bulletins and other technical publications are designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and
3、obtaining with minimum delay the proper product for his particular need. Existence of such Standards, Bulletins and other technical publications shall not in any respect preclude any member or nonmember of CEA from manufacturing or selling products not conforming to such Standards, Bulletins or othe
4、r technical publications, nor shall the existence of such Standards, Bulletins and other technical publications preclude their voluntary use by those other than CEA members, whether the standard is to be used either domestically or internationally. Standards, Bulletins and other technical publicatio
5、ns are adopted by CEA in accordance with the American National Standards Institute (ANSI) patent policy. By such action, CEA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Standard, Bulletin or other technical publication. Note:
6、The users attention is called to the possibility that compliance with this standard may require use of an invention covered by patent rights. By publication of this standard, no position is taken with respect to the validity of this claim or of any patent rights in connection therewith. The patent h
7、older has, however, filed a statement of willingness to grant a license under these rights on reasonable and nondiscriminatory terms and conditions to applicants desiring to obtain such a license. Details may be obtained from the publisher. This CEA Standard is considered to have International Stand
8、ardization implication, but the International Electrotechnical Commission activity has not progressed to the point where a valid comparison between the CEA Standard and the IEC document can be made. This Standard does not purport to address all safety problems associated with its use or all applicab
9、le regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations before its use. (Formulated under the cognizance of the CEA R8 Cable Compatibility Committee.) Published
10、 by CONSUMER ELECTRONICS ASSOCIATION 2002 Technology Phone 800-854-7179; Fax 303-397-2740; Internet http:/; Email 3 Systems for Communicating Copy Protection Methods Implemented between Host and the CA Device The value of CP_system_ID (as used in CEA-679-C, Parts A and B) shall be the system number
11、 defined in Section 4. 3.1 NRSS Part A System Protocols Information concerning commands necessary to use CEA-796-A systems in conjunction with NRSS Part A devices may be found CEA-679-C, Part A, Section 20. 3.2 NRSS Part B System Protocols Information concerning commands necessary to use CEA-796-A s
12、ystems in conjunction with NRSS Part B devices may be found in CEA-679-C, Part B, Section 8.9. 4 Copy Protection Systems When any of the copy protection systems described in Section 4 is implemented, it shall be implemented as indicated in this section. 4.1 System 1Data Scrambling with Diffie-Hellma
13、n Based Keys System 1 is designed to protect data returning from an NRSS module for display to the consumer. Protection is based on three primary principles: a) Restricting the devices that may receive copy protected data. Intellectual property embedded within this copy protection method will requir
14、e a license for manufacture, sale, or use. Licensing terms are designed to prevent devices that facilitate copying unscrambled bitstreams. Devices capable of recording an unscrambled bitstream, capable of making an unscrambled bitstream available for recording, or capable of being readily modified t
15、o record/provide bitstreams will not be granted a license. b) Scrambling data and protecting the keys so that passive devices cannot record signals and decode a clear bitstream. Content data is protected with DES and keys are negotiated using Diffie-Hellman (DH) key exchange. While it is possible to
16、 passively eavesdrop and decode data from the information, it is prohibitively difficult for the value of the data being sent, which is already-purchased A/V content. c) Closely coupling the host and CA module devices so that active devices to record bitstreams are difficult to create. Real-time con
17、straints and complexities make active (man-in-the-middle) devices complex to design and manufacture. 1 Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or netw
18、orking permitted without license from IHS -,-,- CEA-796-A 4.1.1 Licensing Licensing shall be required.1 4.2 System 2-Cryptographic Copy Protection I 4.2.1 Introduction This section describes a mechanism for protecting the interface between the user renewable conditional access module (POD) and the S
19、TB. The mechanism is simple yet secure, and lays the foundation for incorporating evolutionary improvements in the security of STBs, PODs, and key management infrastructures. The mechanism incorporates the following design principles: Localization of vulnerability, so security is a property of the i
20、ntegrity of the two communicating device (i.e., no universal secrets that enable the pirate to leverage off of the compromise of a third device); cryptographic protection of data; IP protected functionality that enables the legal prosecution of circumvention devices; and the fresh authorization of d
21、evices by means of the bi-directional communication inherent in cable systems. 4.2.2 Licensing Licensing shall be required.2 4.3 System 3-Cryptographic Copy Protection II Basics a) Each CE manufacturer generates its own secret-public key pair and has the public key certified by the licensing authori
22、ty (LA). The CE public-key is stored in the “Manufacturer Certificate” in the device. The CE secret-key is used by the CE manufacturer to certify its own individual devices public keys. It is proposed that the certificates be signed and checked using the Fiat Shamir Signature algorithm (FSS). b) For
23、 each CE device, a DH secret-public key pair (x,gx mod p) is generated (perhaps by the device itself). The device DH public key (gx mod p) is certified by the CE device manufacturer. The device DH public key is stored in the “Device-Certificate” c) When two CE devices-the host and the CA module-are
24、connected, they exchange certificates that will enable them to perform an authenticated key exchange and establish a secure channel between them. d) After the certificates are verified, the devices have each others certified DH public key. Using that key, each device continues with the standard DH p
25、rotocol (compute g(x1*x2) mod p, from the received public key and its own secret). This generates a shared key for these two devices. e) To generate a session key, the devices exchange some numbers which are hashed with the shared key above. The session key can be updated as desired by the same hash
26、 mechanism-exchange of numbers and the hash. f) The session key is used to establish a control content channel on which control words and other items can be passed between the Host and CA module. 4.3.1 Licensing Licensing shall be required.3 4.4 System 4Cryptographic Copy Protection III 4.4.1 Intell
27、ectual Property Implementation of the technology described in this section requires a license from the licensing authority and possibly other licenses. 1 For System 1 licensing information, contact: Manager, Licensing-Paris, Thomson multimedia, 46 quai Alphonse Le Gallo, 92648 Boulogne Cedex, France
28、, phone 330 1 41 86 5288, fax 330 1 41 86 0925, Email . 2 For System 2 licensing information, contact: CableLabs, 858 Coal Creek Circle , Louisville, CO 80027- 9750, phone 303 661 9100. 3 For System 3 licensing information, contact: CTO, NDS-TI, Box 23012, Jerusalem, Israel, phone 972-2- 5894444, Fa
29、x 972-2-589-4000, Email or . 2 Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from IHS -,-,- CEA-796-A 4.4.2 Introdu
30、ction This extension adapts the licensed technology to address the specific problem of copy protecting the clear stream as it leaves NRSS CA Modules to go to the host device for display and/or distribution to other devices. This technology is designed to meet several goals: a) To be implementable at
31、 low complexity and in an acceptable timeframe. b) To support management of service, including response to theft of service, by the cable operator. c) To support open competition in retail products, whether single- or multi-function. d) To support content owner (MPAA) and cable operator requirements
32、 for licensing enforcement of content protection requirements in hosts, including revocation of known compromised devices. e) To work across all types of networks: Cable, Terrestrial, and DBS. A back-channel is not guaranteed, consequently the Copy Protection system must work with one-way only chann
33、els. 4.4.3 CA Interface Content Protection Architecture 4.4.3.1 Copy Protection Layers The content protection system addresses four fundamental layers of copy protection: a) Authentication and key exchange b) Content encryption c) Copy control information d) System renewability For the NRSS CA Inter
34、face copy protection, there is an added layer of copy protection: e) CA enforcement 4.4.4 Licensing Licensing shall be required.4 4.5 System 5Open Copy Protection System 4.5.1 Introduction The intent of System 5 is to present an open system where all components are drawn from commonly available stan
35、dards. It is asserted that System 5 methods are interface independent. System 5 specifies a protocol that protects copyrighted material traveling between a removable security element and a consumer electronics (CE) device. In this section, a source is defined as a removable security element, and a s
36、ink is defined as the CE device. 4.5.2 Licensing Licensing shall be required.5 4 For System 4 licensing information, contact: Digital Transmission Licensing Administrator, Acting DTLA President, JF2-53, c/o Intel Corporation, 2111 NE 25th Avenue, Hillsboro, OR 97124, phone 503 264 8426, fax 503 264
37、9027, email dtla-, web http:/ . 5 For System 5 licensing information, contact: Intellectual Property Counsel, Philips, 345 Scarborough Road, Briarcliffe Manor, NY 10510-2099, phone 414 333 9665. 3 Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employee
38、s/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from IHS -,-,- CEA Document Improvement Proposal If in the review or use of this document, a potential change is made evident for safety, health or technical reasons, please
39、 fill in the appropriate information below and email, mail or fax to: Consumer Electronics Association Technology & Standards Department 2500 Wilson Blvd. Arlington, VA 22201 FAX: 703 907-7693 standardsce.org Document No. Document Title: Submitters Name: Telephone No.: Submitters Company: FAX No.: e
40、-mail: Address: Urgency of Change: Immediate: At next revision: Problem Area: a. Clause Number and/or Drawing: b. Recommended Changes: c. Reason/Rationale for Recommendation: Additional Remarks: Signature: Date: FOR CEA USE ONLY Responsible Committee: Chairman: Date comments forwarded to Committee C
41、hairman: Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from IHS -,-,- Copyright Consumer Electronics Association Pro
42、vided by IHS under license with CEA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from IHS -,-,- Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employ
43、ees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from IHS -,-,- Copyright Consumer Electronics Association Provided by IHS under license with CEA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 21:49:11 MDTNo reproduction or networking permitted without license from IHS -,-,-