Design Documentation

The document described in figure 19.5 can be used as sample for a design specification.  Each and every numbered paragraph addresses dissimilar aspects of the design model.   Numbered sections of the design specification are completed as the designer refines her or his representation of the software.

The  whole  scope  of  the  design  effort  is  define  in  section  I   section  numbers  refer  to  design specification   outline   many of the information contained in this section is derived from the system specification, the analysis model  software needs specification.

I.  Scope
A.   System objectives
B.   Major software requirements
C.   Design constraints and limitations

II. Data Design
A.   Resultant data structures and Data objects
B.   Database structures and File
1.   External file structure

      a.    Logical structure
      b.    Logical record description
      c.    Access method

2.    Global data
3.    Data cross reference and File

III. Architectural Design

A.   Control flow and Review of data
B.   Derived program structure

IV. Interface Design
A.   Human-machine interface specification
B.   Human-machine interface design rules
C.   External interface design

     1.   Interfaces to external data
     2.   Interfaces to external systems or devices
D.   Internal interface design rules

V.    Procedural Design
For each module:
A.   Processing narrative
B.   Interface description
C.   Design language or other description
D.   Modules used
E.    Internal data structures
F.    Comments or restrictions or limitations

VI. Requirements Cross-Reference

VII. Test Provisions

1.    Test guidelines
2.    Integration strategy
3.    Special considerations

VIII. Special Notes

IX. Appendices

The Section II represents the data design define external file structures internal data structures, a cross reference which connects data objects to exact files. The Section III the architectural design that indicates how the program architecture has been derived from the analysis model. The Structure diagram is a representation of program structure which is used to represent the module hierarchy.

In the sections IV and V include as procedural design commence and interface. An internal and External program interfaces are represented and a detailed design of the human-machine interface is defined. The Modules individually addressable parts of software like as functions, subroutines or procedures are initially described with an English-language processing narrative. Processing narrative describe the procedural function of a module. Finally, to translate the narrative into a structured description a procedural design tool is used.

In the section VI of the design specification contains a requirement or need cross-reference. With the purpose of this cross- reference matrix is (1) to build in which all needs are satisfied through the software design and (2) to indicate that modules are critical to the implementation of exact requirements.

The  1st  level  in  the  development of  test  documentation is  contained in  section VII  of  the  design document. At once software interfaces and structure have been developed we can establish guidelines for testing of integration and individual modules of the entire package. In several cases a detailed specification of test procedure happens in parallel with design. In the cases this section may be removed from the design specification.

The Design  constraints  like  as  physical  memory  limitations  or  the  necessity  for  a  specialized external interface   may   dictate   special   needs   for   assembling   or   packaging   of   software.   The Special considerations caused through the necessity for program overlay high-speed processing, virtual memory management or other factors may cause modification in design derived from information structure or flow. The considerations and Requirements for software packaging are presented in section VII. The secondarily section define the approach which will be used to transfer software to a customer site.

In the Section IX of the design specification contains supplementary data. In the alternative procedures, Algorithm descriptions, excerpts tabular data from other documents and other relevant information are presented as a special not or as a divide appendix. It may be advisable to establish a preliminary operations or installation manual and include it as appendix to the design document