The purpose of the physical design is to transform the business requirements into physical design specification that will guide the system construction.
In other words, physical design addresses greater details about how technology will be used in the new system. Physical design represents a specific technical solution. For e.g., Diagrams must be converted that map the origin, flow, and processing of data in a system into a structured system design that can then be broken down into smaller and smaller units for conversions to instructions written in a programming language.
One must design the various parts of the system to perform the physical operations necessary to facilitate data capture, processing and information output.
During physical design, the analyst team decides which programming languages the computer instructions will be written in, which database systems and file structures will be used for the data and which hardware platform, operating system and network environment the system will run under.
These decisions finalizes the hardware and software plans initiated at the end of the analysis phase. The final product of the design phase is the physical system specifications, presented in a form, such as diagrams or written report, ready to be turned over to programmers and other system builders for construction.
The design phase is concerned with technology based views of the system —
- Physical database design specification.
- Physical business process and software design specifications.
- Physical user and system interface specifications.
A design must also reflect system integration concern. The new system must be integrated both with other information systems and with the business processes themselves. Integration is usually, reflected in physical system models and design specifications.