Number of external inputs (EIs) - Each external input
originates from a user or is transmitted from another
application and provides distinct application-oriented data
or control information.
• Number of external outputs (EOs) - Each external output is
derived data within the application that provides
information to the user. In this context external output
refers to reports, screens, error messages, etc. Individual
data items within a report are not counted separately.
• Number of external inquiries (EQs) - An external inquiry is
defined as an online input that results in the generation of
some immediate software response in the form of an
online output (often retrieved from an internal logical
file/ILF).
Number of internal logical files (ILFs) - Each
internal logical file is a logical grouping of data
that resides within the application’s boundary
and is maintained via external inputs.
• Number of external interface files (EIFs) -
Each external interface file is a logical
grouping of data that resides external to the
application but provides information that may
be of use to the application.