ITEC 370

Lecture 8Requirements

Requirements

Review

• Requirements–What are some of the characteristics of

a good requirement?–What are use cases?

Requirements

Objectives

• Today– 1 page single spaced 12 pt font

description of your idea

• What to do after you have the requirements document…

Requirements

Acceptance testing

• Have description of how system is supposed to work

• Need– Software that implements the

requirements document– A way for you and the client to agree

that the delivered software works as expected

Requirements

Acceptance testing

• Users need to see the software working

• Could just send a .exe and say done…

• Better way– Scripted demonstration– Pre-determined– Trial period for usage

Requirements

Issues

• Lawyer needed• After software is built who owns it?• Tech-support / Maintenance support• Updates to the project

Requirements

Examples

• Company X sells bread to supermarkets using employees who sell and deliver bread from vans.

• The are currently using paper forms and would like to move to an electronic system.

• They want this system to feed into SAP, which will automatically keep the accounts up to date and generate all the necessary paperwork for the customer.

• The users will typically be from a weak educational background and have no computer skills, this the system must be very easy to use and easy to train.

• The system must be quicker to use in the field than the existing paper system

• The hardware must be rugged enough to work in a harsh environment in low light conditions. e.g. IP76, and backlit screens.

• The cost of the system must be no more than $5k per user

From stackoverflow

Given this description where does thisgo in the SRS?What are the stages needed to completeThe SRS with this information?

Requirements

Details

• Split up for traceability• From Karl E. Wiegers

1. Status Messages.

1.1. The Background Task Manager shall display status messages in a designated area of the user interface at intervals of 60 plus or minus 10 seconds.

1.2. If background task processing is progressing normally, the percentage of the background task processing that has been completed shall be displayed.

1.3. A message shall be displayed when the background task is completed.

1.4. An error message shall be displayed if the background task has stalled.

http://www.processimpact.com/articles/qualreqs.html

Requirements

Use cases

• Describe what the user is going to doOne potential method for each requirement:Use case namePriorityTriggerPre-conditionBasic path (List of how this feature works)Alternate pathExceptionsReferences

Requirements

When you are done

• Read the requirement as if you are the developer

• With just what is on the paper in front of you, could you implement it?

• Can you trace the requirement back to the customer?

• Can the developer see the trace and understand it?

Requirements

Example

• A requirement document I put together for my dissertation

• Not a typical document, but uses part of the process to help illustrate needs for the system

Requirements

Review

• Requirements– Good requirements– Bad requirements