摘要:
In a peer-to-peer environment, copyrights and users' privacies can be protected by a tracking mechanism. In described implementations, tracking mechanisms can use certificates that are produced using random numbers to protect the privacy of users and/or certificates that are produced responsive to at least one hardware identifier to enable uploader to be identified to protect copyrights.
摘要:
In a peer-to-peer environment, copyrights and users' privacies can be protected by a tracking mechanism. In described implementations, tracking mechanisms can use certificates that are produced using random numbers to protect the privacy of users and/or certificates that are produced responsive to at least one hardware identifier to enable uploader to be identified to protect copyrights.
摘要:
Systems and methods providing ciphertext switching for syntax compliant encryption are described. In one aspect, intermediate ciphertext is generated from syntax compliant plaintext. Post-processing is applied to the intermediate ciphertext to determine if there are any illegal symbols in the intermediate ciphertext. If an illegal symbol is located, the illegal symbol in the intermediate ciphertext is switched with a corresponding plaintext symbol. One or more iterations of the post-processing and switching operations result in syntax compliant ciphertext.
摘要:
A public licensing infrastructure (PLI) for a digital rights management (DRM) system is described. In an implementation, a method includes generating a formal license for content. The formal license includes a decryption key for decrypting the content and access rules for accessing the content. A plurality of license authorities is configured to provide a plurality of partial licenses. The plurality of partial licenses is combinable to form the formal license. Each license authority provides a respective partial license.
摘要:
Key management is performed to generate a single key allowing of the decoding of all authorized levels of a plurality of access types within a scalable codestream. An access node set is derived from sets representing access types having hierarchies representable by fully ordered sets, such as resolution and layer levels, and hierarchies representable by partially ordered sets, such as tile and precinct levels. The access node set derived is a partially ordered set representing the combinations of levels of the access types included within the codestream. A hierarchical key management system is applied to the access node set to assign a key to each of the access nodes, generate content encryption keys, and encrypt the codestream. A client receiving the codestream, access node set, and other public information uses the key to derive additional keys to decrypt the codestream.
摘要:
A public licensing infrastructure (PLI) for a digital rights management (DRM) system is described. In an implementation, a method includes generating a formal license for content. The formal license includes a decryption key for decrypting the content and access rules for accessing the content. A plurality of license authorities is configured to provide a plurality of partial licenses. The plurality of partial licenses is combinable to form the formal license. Each license authority provides a respective partial license.
摘要:
Subject matter includes exemplary systems and related methods for fully scalable encryption of scalable multimedia. A scalable bitstream encrypted using the subject matter maintains full functionality of scalable features in the encrypted form. The exemplary scalable encryption allows transcoding, rate shaping, and other operations directly on the ciphertext without degradation of scalable compression efficiency and error resiliency.
摘要:
An exemplary digital rights management engine and related methods divides multimedia content into service level layers, encrypts at least some of the layers, and offers access to the encrypted layers by permission. The multimedia content may be layered using multiple different layering approaches simultaneously, and access to the different types of layers may be offered simultaneously. One of the layers may be left unencrypted to allow free browsing of a low quality service level. An exemplary system of key management for digital rights management is also disclosed.
摘要:
Systems and methods configured for recoding an odd integer and elliptic curve point multiplication are disclosed, having general utility and also specific application to elliptic curve point multiplication and cryptosystems. In one implementation, the recoding is performed by converting an odd integer k into a binary representation. The binary representation could be, for example, coefficients for powers of two representing the odd integer. The binary representation is then configured as comb bit-columns, wherein every bit-column is a signed odd integer. Another implementation applies this recoding method and discloses a variation of comb methods that computes elliptic curve point multiplication more efficiently and with less saved points than known comb methods. The disclosed point multiplication methods are then modified to be Simple Power Analysis (SPA)-resistant.
摘要:
A fast and secure syntax compliant encryption schema, “locally iterative encryption,” can produce compliant ciphertext for a general syntax specification. In one implementation, an engine partitions a data stream into blocks, and encrypts each block iteratively until syntax compliance conditions are met. A system using the schema can utilize either stream ciphers or block ciphers in different modes. Locally iterative encryption methods are fast and remain at approximately the same speed even as the length of the data stream to be encrypted increases. Besides providing superior processing speed, the locally iterative encryption schema is also more robust to errors in the resulting ciphertext and in the resulting decrypted plaintext than conventional syntax compliant encryption techniques. Locally iterative encryption is secure as long as an underlying encryption cipher selected for use in the schema is secure.