The key factor in producing a useful physical design is the ability both for users to understand the true scope of the system and for the implementation team to be able to use it for program, data, and interface design.

Physical design is devoted to creating specifications that establish the physical environment within which the system will operate, the physical characteristics of the system, and how it will physically function.

Steps in Physical Design

1. Identify resources needed to meet user needs.
2. Identify procedures necessary to meet user needs.
3. Describe the procedures so that computer code can be generated
4. Describe data so that stored data can be created or modified.
5. Identify additional technology necessary for the new or modified system

The finished Physical design of a solution should contain:

1.Alternative solutions to the problem - in what different ways could the problem be solved?

There is rarely only one way to solve a problem. The challenge is to find the most effective and efficient method for that particular organisation for that particular problem. "what is appropriate" will vary from case study to case study. We must always decide on the best solution based on the case study you are given.

How to find alternatives:

See what other organisations have done in similar situations.

Investigate what tools are available that may help solve the problem (e.g. it may turn out that a spreadsheet would be better than a database to solve a particular problem)

Brainstorm: invite ideas and put them all down regardless of how silly they may seem. Sometimes an "off the wall" lateral-thinking suggestion may inspire a creative solution.

Ask for opinions from experts Ask for hardware/software manufacturers to explain why their product is the best choice

2.Data structure (e.g. field names, data types and lengths, filenaming, folder structure schemes, colour coding, style guide requirements).

3.Data input procedures and equipment (e.g. keyboard? barcode reader? OCR?)

4.Interfaces (e.g. what will a data entry screen look like? Will people need to leave the main screen to access functions? How will menus be organised into commands and submenus? What shortcut keys will be used? Will you use a text box, listbox, combo box, tickbox for a particular item of data entry? What colour scheme will be used? What navigation scheme will be used? What icons represent what meaning? Will the layout of the data entry form help users enter data in the required order and the required format?

5.Control procedures - What validation rules will be used on what fields to check for data reasonableness, existence or format?) What will different error messages say? How can output be checked for accuracy (e.g. an average can be compared with the data items from which it was calculated). How can procedural errors or problems be detected? (e.g. an order may be cross-checked against the stock database to ensure the ordered item is in stock, or whether it needs to be backordered and the potential customer notified of the delay).

6.Equipment sources - will equipment be tailor-made or 'off the shelf'? In either case, hardware and software specifications must be given.

7.What workloads and capacities the system must be capable of - e.g. storage capacities, number of transactions per hour, disaster-recovery abilities

8.Validation and storage methods to be used

9.How to produce the output (i.e. processing actions)

10.Procedures to be followed to use the solution

11.Backup requirements and procedures - what needs to be backed up, how often, how backups are stored, what backup scheme will be used?

12.How the solution is to be tested to ensure it works properly - what needs to be tested? Functionality, presentation, usability, accessibility, communication of message. How will you test?

13.Staffing requirements to use the solution (e.g. new experts or operators, moving workers to new areas)

14.Changeover - how will the solution be brought online to replace the existing system (implementation strategy)

15.Evaluation - how is the finished solution going to be evaluated to see if it meets expectations

A system flow chart, or data flow chart, is used to describe the flow of data through a complete data-processing system. Different graphic symbols represent the clerical operations involved and the different input, storage, and output equipment required. Although the flow chart may indicate the specific programs used, no details are given of how the programs process the data. In other words, it's like a DFD

A program flow chart is used to describe the flow of data through a particular computer program, showing the exact sequence of operations performed by that program in order to process the data. Different graphic symbols are used to represent data input and output, decisions, branches, and subroutines.

The physical design should finish with a documented system specification.