Note: Correction to the 1997 tutorial on Reed–Solomon coding

In 1997, SPE published a tutorial by Plank [19] on implementi ng Reed-Solomon codes for erasure correction in redundant data storage systems. The motivation of this tutori al was to present these codes, which are typically described mathematically by coding theorists, in a way accessible to t he programmers who need to implement them. The tutorial as published presented an information dispersal matrix A, which does not have the properties claimed – that the deletion of anym rows results in an invertable n n matrix. The purpose of this note is to present a correct infor mation dispersal matrix that has the desired properties, and to put the work in current context.