Home > Storage > PowerScale (Isilon) > Product Documentation > Management and Migration > Storage Tiering with Dell PowerScale SmartPools > Hardware tiers
Heterogeneous OneFS clusters can be architected with a wide variety of node styles and capacities to meet the needs of a varied dataset and wide spectrum of workloads. These node styles fall loosely into four main categories or tiers. The following figure illustrates these tiers, and the associated hardware models: