This draft second edition European Telecommunication Standard (ETS) defines terms commonly used in ETSs on the subject of Private Integrated Services Networks (PISNs). The purpose of defining terms and definitions is to guide the further specification of PISN capabilities and to permit consistency of interpretation between ETSs containing such specifications. The terms and definitions given in this ETS apply to the technical aspects of PISNs. They do not address legal or regulatory issues. An ETS shall be deemed to be in compliance with this ETS if it uses terms with the meanings as defined by this ETS. Terms not defined here may be defined context-specific in the relevant standards or technical reports.