CPF was an example of a commercially-available [[Capability-based operating system]]. System/38 was one of the few commercial{{Citation needed| date=July 2007}} computers with [[capability-based addressing]].<ref>{{cite (Thebook earlier| [[Plessey]]chapter-url [[Plessey= Systemhttp://www.cs.washington.edu/homes/levy/capabook/Chapter8.pdf 250|250]]wastitle one= ofCapability-Based theComputer fewSystems other| computerschapter with= capabilityThe architectureIBM everSystem/38 sold| commerciallyfirst = Henry M.) | last = Levy | publisher = Digital Press | year = 1984 | isbn = 0-932376-22-3}}</ref> Capability-based addressing was removed in the follow-on [[AS/400]] and [[iSeries]] models.<ref name = "Soltis2001">{{cite book | first1 = Frank G. | last1 = Soltis | url = https://books.google.com/books?id=ypJmzqt7JdUC | title = Fortress Rochester: The Inside Story of the IBM ISeries | page = 119 | publisher = 29th Street Press | date = July 2001 | isbn = 978-1-58304-083-6}}.</ref> [[Capability-based operating system]] refers to an operating system that uses [[capability-based security]].
