It's getting harder to distinguish between a low-end enterprise array and a high-end midrange array--but there are still some important differences.

High-end midrange arrays and low-end enterprise arrays look awfully similar these days. During the last few years, features like clustering, mirrored cache, replication and snapshots have trickled down from enterprise arrays, while low-priced SATA drives have moved up to enterprise arrays to further confuse the already somewhat arbitrary array classifications.

The midrange array category is getting bigger, a catchall of low-end commodity systems and high-end arrays with specialized features. But there are distinct differences in array architectures in the midrange category that vendors don't advertise.