What is Erasure (n+k) ?

For Erasure Coding, "n+k" denotes the number of nodes that each block of data is split into, encoded and stored upon. The "n" denotes the number of pieces for the original data, while "k" is number of pieces for redundancy, equal to the number of nodes you can lose in a cluster (resilience) and still have all data readable. To avoid hotspots, the destination for all pieces are mixed, and at all times, any n of the n+k pieces can be used to read data. The minimum number of nodes in a Compuverde cluster is n + k + 1.