A system for software error-correcting code (ECC) protection or compression of original data using ECC data in a first memory is provided. The system includes a processing core for executing computer instructions and accessing data from a main memory, and a non-volatile storage medium for storing the computer instructions. The software ECC protection or compression includes: a data matrix for holding the original data in the first memory; a check matrix for holding the ECC data in the first memory; an encoding matrix for holding first factors in the main memory, the first factors being for encoding the original data into the ECC data; and a thread for executing on the processing core. The thread includes a Galois Field multiplier for multiplying entries of the data matrix by an entry of the encoding matrix, and a sequencer for ordering operations using the Galois Field multiplier to generate the ECC data.

Embodiments relate to the emulation of the effect of Forward Error Correction (FEC) codes, e.g., GF.sup.10 Reed Solomon (RS) FEC codes, on the bit error ratio (BER) of received Pseudo-Random Binary Sequences (PRBS) patterns. In particular, embodiments group errors into RS-FEC symbols and codewords in order to determine if the errors are correctable. By emulating the error correction capabilities of FEC codes in order to determine which errors are correctable by the code, embodiments afford a more accurate representation of the post-FEC BER of RS FEC codes from links carrying PRBS patterns. This FEC code emulation provides error correction statistics, for stand-alone use or for error correction in connection with Bit Error Rate Testers (BERTs).

A method (400) of generating a cryptographic checksum for a message M(x) is provided. The method is performed by a communication device, such as a sender or a receiver, and comprises calculating (405) the cryptographic checksum as a first function g of a division of a second function of M(x), (M(x)), modulo a generator polynomial p(x) of degree n, g((M(x))mod p(x)). The generator polynomial is calculated (403) as p(x)=(1x).Math.P.sub.1(x), and P1(x) is a primitive polynomial of degree n1. The primitive polynomial is selected (402), based on a first cryptographic key, from the set of primitive polynomials of degree n1 over a Galois Field. By replacing a standard checksum with a cryptographic checksum, an efficient message authentication is provided. The proposed cryptographic checksum may be used for providing integrity assurance on the message, i.e., for detecting random and intentional message changes, with a known level of security. The proposed checksum is capable of detecting double-bit errors which may be introduced by a Turbo code decoder.

Systems, methods, and computer-readable media are disclosed for performing reduced latency error decoding using a reduced latency symbol error correction decoder that utilizes enumerated parallel multiplication in lieu of division and replaces general multiplication with constant multiplication. The use of parallel multiplication in lieu of division can provide reduced latency and replacement of general multiplication with constant multiplication allows for logic reduction. In addition, the reduced symbol error correction decoder can utilize decode term sharing which can yield a further reduction in decoder logic and a further latency improvement.

Systems and techniques described herein include jointly decoding coded data of different codes, including different coding algorithms, finite fields, and/or source blocks sizes. The techniques described herein can be used to improve existing distributed storage systems by allowing gradual data migration. The techniques can further be used within existing storage clients to allow application data to be stored within diverse different distributed storage systems.

To reduce the processing amount of a field multiplication. a denotes a k-th order vector whose elements are a.sub.0, . . . , a.sub.k1 (a.sub.0, . . . , a.sub.k1GF(x.sup.q)). A denotes an n-by-k matrix formed by vertically connecting a identity matrix and a Vandermonde matrix. b denotes an n-th order vector obtained by multiplying the vector a and the matrix A whose elements are b.sub.0, . . . , b.sub.n1 (b.sub.0, . . . , b.sub.n1GF(x.sup.q)). A vector conversion part 11 generates a -th order vector b using elements b.sub.p0, . . . , b.sub.p1 of the vector b. An inverse matrix generation part 12 generates a -by- inverse matrix A.sup.1. A plaintext computation part 13 computes elements a.sub.e0, . . . , a.sub.e1 of the vector a by multiplying the vector b and the inverse matrix A.sup.1.

Techniques are described for joint encoding and decoding of information symbols. In one embodiment, a method for joint encoding includes, in part, obtaining a sequence of information symbols, generating a plurality of cyclic codewords each corresponding to a portion of the sequence of information symbols, jointly encoding the plurality of cyclic codewords to generate at least one combined codeword, and providing the combined codeword to a device. The at least one combined codeword may be generated through Galois Fourier Transform (GFT). In one embodiment, a method for joint decoding includes, in part, obtaining a sequence of encoded symbols, wherein the sequence of encoded symbols is generated through GFT, jointly decoding the sequence of encoded symbols using an iterative soft decision decoding algorithm to generate a decoded sequence, transforming the decoded sequence to generate a plurality of cyclic codewords, and decoding the plurality of cyclic codewords to generate a plurality of decoded information symbols.

Embodiment herein provide a Bose-Chadhuri-Hocquenghem (BCH) encoder for generating a BCH signal. The BCH encoder (1) includes a memory for storing a minimum distance to be used for generating the BCH signal for a BCH code (n, k) and a polynomial generator for generating a generator polynomial for the BCH code (n, k) and encoding the generator polynomial to obtain the BCH signal. The polynomial generator includes a set of k registers (4) connected in series to receive the information bits and output an encoded bit based on a clock signal, a first gate (5) to receive a code length, a number of information bits, and the minimum distance as input, a second gate (6), and a finite field adder circuit (7) for determining a finite field sum of the output of each register of the set of k registers (4).

A system using accelerated error-correcting code in the storage and retrieval of data, wherein a single-instruction-multiple-data (SIMD) processor, SIMD instructions, non-volatile storage media, and an I/O controller implement a polynomial coding system including: a data matrix including at least one vector and including rows of at least one block of original data; a check matrix including more than two rows of at least one block of check data in the main memory; and a thread that executes on a SIMD CPU core and including: a parallel multiplier that multiplies the at least one vector of the data matrix by a single factor; and a parallel linear feedback shift register (LFSR) sequencer or a parallel syndrome sequencer configured to order load operations of the original data into at least one vector register of the SIMD CPU core and respectively compute the check data or syndrome data with the parallel multiplier.

The disclosure provides a very flexible mechanism for a storage controller to create RAID stripes and to re-create corrupted stripes when necessary using the erasure coding scheme. Typically, this is known as a RAID 6 implementation/feature. The erasure code calculations are generated using the Galois Multiplication hardware and the system controller can pass any polynomial into the hardware on a per stripe calculation basis. The polynomial value is passed to the hardware via an input descriptor field. The descriptor controls the entire computation process.