摘要:
A method and system is provided facilitating tracing copies of an implementation of a computational method where different versions of a network of look-up tables representing steps of the computational method are generated, and stored in a memory, each version being unique so that output encodings and/or input decodings of the white-box implementations of the computational method are different in the different versions. The network is formed by using an output value of a first look-up table as an input value of a second look-up table. The different versions are generated by changing at least one value in the network, end results of the version corresponding to a relevant domain of input values being substantially the same for each version. A method and system for computation for a user with the corresponding version in the memory, and/or for identifying a copy of an implementation of the computational method is provided.
摘要:
A system (600) for facilitating tracing copies (634) of an implementation of a computational method (602). A network generator (604) for generating a network of look-up tables representing steps of the computational method (602), the network being formed by using an output value of a first look-up table as an input value of a different second look-up table. A personalizer (606) for generating a plurality of different versions of the network of look-up tables by changing at least one value in the network of look-up tables, end results of the version corresponding to a relevant domain of input values being substantially the same for each version. An associator (608) for associating individual versions with individual stations (610) or users (632) of stations (610). The computational method (602) includes a 10 cryptographic scheme and a cryptographic key.
摘要:
A method of generating digital test patterns for testing a number of wiring interconnects is described. A first set of test patterns is generated; the number of test patterns in the first set is related to said number of wiring interconnects, and defines a first set of code words. From the first set of code words, a second set of code words is selected. The number of code words in the second set is equal to said number of wiring interconnects, and the selection of the second set of code words is such that the sum of the transition counts for the code words in the second set is minimized.
摘要:
The invention relates to a modulation code system and a corresponding modulation method. Said modulation system comprises an encoder 100 for transforming an original signal s into an encoded signal c satisfying predefined second constraints. Said modulation code system further comprises a decoder 200 for decoding the encoded signal c after restoration back into the original signal s. It is the object of the invention to improve such a known modulation code system and method in the way that the amount of required hardware is reduced. This object is solved according to the invention by designing the encoder 100 such that it comprises a series connection of a modulation code encoder 110 and of a transformer encoder 120 serving for filtering an intermediate signal t output by said modulation code encoder 110 and satisfying predefined first constraints in order to generate said encoder output signal c. The object is further solved by the decoder 200 comprising a series connection of a transformer decoder 220 and of a modulation code decoder 210.
摘要:
A data tag containing self-descriptive data, a method for reading such a data tag and a system for interpreting such a data tag are disclosed. Characterizing information about a first data element stored in a memory of the data tag is stored in a first header preceding a first data element. In addition, characterizing information about a second data element stored in the memory of the data tag is stored in a second header preceding a second data element. The application of a multitude of descriptive headers, each characterizing a data element stored in the data tag memory, facilitates flexible data storage on such devices. Furthermore, it also facilitates data compression due to the fact that field lengths can be characterized as well, thus excluding the presence of redundant bits in the data stored in the memory.
摘要:
A method and apparatus for compressing test vector data for use in testing a logic product, wherein original test vector data is generated in the form of two or more sequences of bits including “care” bits and “don't care” bits. The test vector data is then compressed by comparing corresponding bits of two or more subsequent vectors and merging the two or more vectors into a single vector representative thereof if all of the corresponding bits of the two or more vectors are found to be compatible. Compatibility of two bits is achieved if they do not have specifically incompatible or opposite values.