An XOR based reed-solomon algorithm for advanced RAID systems

Abstract

In this paper, a simple codec algorithm, based on Reed-Solomon (RS) codes, is proposed for erasure correcting in RAID (redundant array of independent disks) level 6 systems. Unlike conventional RS codes, this scheme, with a mathematical reduction method, called reduced static-checksum table approach, could improve coding performance, including encoding and decoding procedures. This scheme uses current industrial RAID-5 controllers as well as the regular hardware, and is without extra cost in adding any new equipment. Moreover, our algorithm is able to expand to correct multiple failed-disks while others, EvenOdd codes for example, cannot do so. Also, this scheme performs all computations with only simple exclusive-OR (XOR) operators, the same as EvenOdd codes. For most RAID architectures, this new XOR-based RS code could adapt to implementation in terms of reliability, flexibility and lower cost.