CS605 Software Engineering-II Assignment No.2 Solution FALL 2014

Question No. 1

Solution:

Internal Logical File

ILF stands for "Internal Logical File". In my words, ILFs represent data that is stored and maintained within the boundary of the application you are counting. When counting ILFs you are basically counting the data functions that your application is being built to maintain.

The more precise IFPUG definition of an ILF is:

"An ILF is a user-identifiable group of logically related data or control information maintained within the boundary of the application. The primary intent of an ILF is to hold data maintained through one or more elementary processes of the application being counted."

Furthermore, for data or control information to be counted as an ILF, both of the following IFPUG counting rules must also apply:

1. The group of data or control information is logical and user identifiable.
2. The group of data is maintained through an elementary process within the application boundary being counted.

Internal Logical Files (ILF) - a user identifiable group of logically related data that resides entirely within the application boundary and is maintained through External Inputs. An internal logical file has the inherent meaning it is internally maintained, it has some logical structure and it is stored in a file.

External Interface Files

External Interface Files (EIF) - a user identifiable group of logically related data that is used for reference purposes only. The data resides entirely outside the application boundary and is maintained by another applications external input. The external interface file is an internal logical file for another application. An application may count a file as either a EIF or ILF not both. An external interface file has the inherent meaning it is externally maintained (probably by some other application), an interface has to be developed to get the data and it is stored in a file.

FUNCTIONAL OVERVIEW

Data used by elementary processes to maintain records on an Internal Logical File within an application may originate from a number of different sources:

1.     External non-system sources.

Sourced from external manual procedures and entered by system users via on-line screens.

1.     Other computer systems:

·         via transferred files

·         via direct on-line real-time information requests

1.     The system itself.

·         Data from internal reference files may contribute to a master business transaction.

·         Stored data may be used to generate new data that must be stored (and cannot be re-created at a future time).

Question No. 2

Solution:

For a certain requirement specification note the following:

Nnf = Non-functional requirements = 15

Nf = Functional requirements = 35

Nui = number of requirements for which all reviewers had identical interpretation = 10

Calculate the “Lack of Ambiguity” in the requirements given in specification. Marks 8

Answer:

The numbers of requirements are calculated as:

nr = nf + nnf

nr = 35+15 = 50

Now lack of ambiguity in the requirements is calculated as:

Q= nui/nr

= 10/50 = ()      Answer