Various elements of function points FTR, ILF, EI

Question

Explain the various elements of function points FTR, ILF, EI, EQ, EIF, EO, and GSC?

Answer 1

a) File Type References (FTRs) : It is a file or data referenced by a transaction. FTR should be an ILF or EIF. During the process count each ILF or EIF. By default you will always have one FTR in any EP because If the EP is maintained as an ILF then count that as an FTR.

b) Internal Logical Files (ILFs) : They are logically related data from a user's view point. They are maintained during the elementary process of the application and reside in the internal application boundary. It can have a maintenance screen but not always.

c) External Input (EI) : It is a dynamic elementary process in which data is received from the external application boundary. Example: - In User interaction screens, data comes from the User Interface to the Internal Application.

d) External Inquiry (EQ) : EQ is a dynamic elementary process in which result data is retrieved from one or more ILF or EIF. In this EP some input requests have to enter the application boundary. Output results exits the application boundary.

e) External Interface Files (EIFs) : EIFs reside in the external application boundary. EIFs are maintained by external applications not by internal applications. They are used only for reference purposes.

f) External Output (EO) : They are dynamic elementary processes in which derived data crosses from the internal application boundary to the external application boundary.

g) General System Characteristics (GSCs) : It is the most important section. All the previously discussed sections relate only to applications. But there are other things also to be considered while making software, such as are you going to make it an N-Tier application, what's the performance level the user is expecting, etc. These other factors are called GSCs.