IBM i Software Tier
IBM's per-core licensing bracket for IBM i (P05, P10, P20, P30, P50) that sets your annual or perpetual software cost based on processor feature code, independent of the Power generation running underneath it.
Every IBM i partition is licensed at a software tier tied to its processor feature code. The tier's per-core price is set by IBM regardless of hardware generation, so the real cost lever is how many cores a given generation needs to clear a tier's performance ceiling -- see IBM i Tier Economics for the full breakdown.
Related Terms
Subscription Licensing
IBM's pay-per-year IBM i licensing model, billed per core per year, introduced as an alternative to perpetual (one-time) licensing.
Perpetual Licensing
IBM's traditional one-time-purchase IBM i licensing model, paid once per core rather than annually.
Cost per CPW
Acquisition or ownership cost divided by CPW capacity delivered -- the core cost-efficiency measure used across this site's Market Price analysis.