摘要:
Biometric parameters acquired from human forces, voices, fingerprints, and irises are used for user authentication and access control. Because the biometric parameters are continuous and vary from one reading to the next, syndrome codes are applied to determine biometric syndrome vectors. The biometric syndrome vectors can be stored securely while tolerating an inherent variability of biometric data. The stored biometric syndrome vector is decoded during user authentication using biometric parameters acquired at that time. The syndrome codes can also be used to encrypt and decrypt data.
摘要:
Biometric parameters acquired from human forces, voices, fingerprints, and irises are used for user authentication and access control. Because the biometric parameters are continuous and vary from one reading to the next, syndrome codes are applied to determine biometric syndrome vectors. The biometric syndrome vectors can be stored securely while tolerating an inherent variability of biometric data. The stored biometric syndrome vector is decoded during user authentication using biometric parameters acquired at that time. The syndrome codes can also be used to encrypt and decrypt data.
摘要:
A method compresses a set of correlated signals by first converting each signal to a sequence of integers, which are further organized as a set of bit-planes. This can be done by signal transformation and quantization. An inverse accumulator is applied to each bit-plane to produce a bit-plane of shifted bits, which are permuted according to a predetermined permutation to produce bit-planes of permuted bits. Each bit-plane of permuted bits is partitioned into a set of blocks of bits. Syndrome bits are generated for each block of bits according to a rate-adaptive base code. Subsequently, the syndrome bits can be decompressed in a decoder to recover the original correlated signals. For each bit-plane of the corresponding signal, a bit probability estimate is generated. Then, the bit-plane is reconstructed using the syndrome bits and the bit probability estimate. The sequence of integers corresponding to all of the bit-planes can then be reconstructed from the bit probability estimates, and the original signal can be recovered from the sequences of integers using an inverse quantization and inverse transform.
摘要:
Appropriate determinations in a series of tests, which transition from more passive tests to more active tests, control the admission of data streams onto a network data path. More passive tests can include promiscuous mode and packet-pair tests. When the results of more passive tests indicate a reduce likelihood of a data stream causing a network data path to transition into a congested state, the network data path can be actively probed to make a more precise determination on the likelihood of congestion. A train of diagnostic data packets is transmitted at a diagnostic data transfer rate having a significantly reduced chance of causing congestion. A train of target data packets is transmitted at a requested application transfer data rate. The number of target data packets received within a specified delay threshold is compared to the number of diagnostic data packets receive with the delay threshold.
摘要:
An error correction code includes a separate error code portion for each of two or more separate burst erasure durations (or burst error durations). For each burst erasure duration, the code can be employed to recover from the burst erasure with a different delay time. Each error code portion has a particular parameter for burst duration (B) and delay (T), meaning that the code can be used to recover from a burst erasure of duration B with delay T. Each error code portion is based on separating the source symbols into sub-symbols and diagonally interleaving the sub-symbols based on the (B,T) parameters for the error code portion. Accordingly, different burst erasures are recovered from with different delays.
摘要:
An error correction code includes a separate error code portion for each of two or more separate burst erasure durations (or burst error durations). For each burst erasure duration, the code can be employed to recover from the burst erasure with a different delay time. Each error code portion has a particular parameter for burst duration (B) and delay (T), meaning that the code can be used to recover from a burst erasure of duration B with delay T. Each error code portion is based on separating the source symbols into sub-symbols and diagonally interleaving the sub-symbols based on the (B,T) parameters for the error code portion. Accordingly, different burst erasures are recovered from with different delays.