ITEC 370 Lecture 8 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 this go in the SRS? What are the stages needed to complete The SRS with this information?

Requirements Details Split up for traceability From Karl E. Wiegers 1. Status Messages 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 If background task processing is progressing normally, the percentage of the background task processing that has been completed shall be displayed A message shall be displayed when the background task is completed An error message shall be displayed if the background task has stalled.

Requirements Use cases Describe what the user is going to do One potential method for each requirement: Use case name Priority Trigger Pre-condition Basic path (List of how this feature works) Alternate path Exceptions References

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