EC = error correction? erasure = we know the place of failure (erroneous stripe) error (silent data corruption) = we do NOT know the place of failure $ P $ and $ Q $ --- syndromes? If $ D_0,\dots,D_{k-1} $ --- information strips, then $$ P=D_0+D_1+\dots+D_{k-1}, \quad ( + = XOR ) $$ $$ Q=D_0\mathfrak A^{k-1}+ D_1\mathfrak A^{k-2}+\dots+D_{k-1} $$ where $ \mathfrak A $ stands for a primitive element of the finite field. Is this true?