SOFT 423: Software Requirements

Transcription

1 SOFT 423: Software Requirements Week 3 Class 1 Finish Elicitation & Start Analysis SOFT 423 Winter

2 Last Class Questionnaires Document Inspection Requirements Stripping Use Cases Scenarios SOFT 423 Winter

3 This Class Finish Elicitation Start Analysis IEEE Standard Document Format SOFT 423 Winter

4 Workshop Designed to encourage consensus Gather key stakeholders Short intensive period (1-2 days) Facilitator (team or outside) output: preliminary system definition at the feature level Benefits: Team building All stakeholders get a say Forges agreement can expose political issues output is available immediately SOFT 423 Winter

5 Workshop Issues Early or late in the elicitation process? different goals. participation of right stake holders easy in late workshops Minimum size is 7 (from different stakeholder groups) Logistics room, equipment travel/audio/visual conferencing set the tone of the meeting amateur vs professional SOFT 423 Winter

6 Workshop Issues Warm up material sets the frame of mind project specific information attempts to encourage out of box thinking ( Forget all you know about possible ) Facilitator some training/experience required demonstrated team building skills respected may have to go outside organization strong SOFT 423 Winter

7 Brainstorming Primary function of workshops Can also be used separately in shorter meetings Not quite the same as an open interview interview is a small meeting with a single group of stakeholders In brainstorming, more than one stakeholder group is represented minimum size of 7 SOFT 423 Winter

8 Brainstorming Benefits Encourages participation by all parties Allows participates to benefit and augment each others ideas High bandwidth of information Results in a broad set of possible solutions to the problem Typically encourages out-of-box thinking SOFT 423 Winter

9 Brainstorming Free for all No criticism is allowed Generate as may ideas as possible Fast pace Mutate and combine ideas Starting questions: what features would you like to see? what services should the system provide? what things would you like the system to keep track of? SOFT 423 Winter

10 Brainstorming Recording Everything is recorded If possible, capture ideas by the generator own words prevent delays Flip Charts Post it Notes 1 idea / sheet Overheads (SCAM) SOFT 423 Winter

11 Brainstorming: Idea Reduction Pruning ideas that are not to be pursued presence of prune able ideas is a quality metric, lack of them means not wide enough discussion Grouping related ideas new features performance enhancements to current features UI, ease of use etc. SOFT 423 Winter

12 Brainstorming: Idea Reduction Feature Definition what did the idea mean to the person that submitted it expansion of the meaning of the idea Prioritization not everything can be done critical/important/useful SOFT 423 Winter

13 Brainstorming Drawbacks Recent research has indicated that brainstorming presents some social boundaries to requirements discovery Having members from both management and low-level implementation personnel may be intimidating, causing many opinions to not be shared Present does not always mean participating SOFT 423 Winter

14 Requirements Analysis SOFT 423 Winter

15 Analysis Through study of a problem domain, the achievement of understanding and documentation of the characteristics of that domain and the problems that exist within the domain Leaves specification as a separate task invention and documentation of the solution system that will fulfill the requirements SOFT 423 Winter

16 Analysis Input is all of the elicitation information Output goes several ways back to elicitation, requesting more info the requirements document understanding for use in building a specification SOFT 423 Winter

17 Overall Requirements - Reminder Problem Domain Interface Solution System SOFT 423 Winter

18 Overall Requirements - Reminder Task: Analysis Specification Design Problem Domain Interface Solution System SOFT 423 Winter

19 Overall Requirements - Reminder Task: Analysis Specification Design Problem Domain Interface Solution System Output: Requirements Document Specification Document Design Document SOFT 423 Winter

20 Overall Requirements Possible to put both Requirements and Specifications Document into the same physical document, but must have both content IEEE standard document has both in a single document SOFT 423 Winter

21 IEEE/ANSI Multiple defined sections 1.Introduction 1.1 Purpose 1.2 Scope 1.3 Definitions 1.4 Acronyms 1.5 Overview of Rest SOFT 423 Winter

22 IEEE/ANSI General Description 2.1 Perspective 2.2 Functions 2.3 User Characteristics 2.4 General Constraints 2.5 Assumptions and Dependencies SOFT 423 Winter

23 IEEE/ANSI Specific Requirements functional, non-functional and interface requirements meat of the document headings for each class of requirements you define the classes 4.Appendices 5. Index SOFT 423 Winter

24 Document Standards IEEE is a starting point very general form adapt standard depending on system and circumstances Organizations adopt a standard flexibility is important required and optional sections SOFT 423 Winter

25 Requirements Document [Bray] Complete description of the relevant parts of the problem domain structure of problem domain problem domain data events and phenomena properties and behaviour of problems Client Requirements (complete?) effects that the solution system should produce within the problem domain SOFT 423 Winter

26 General Problems during Analysis Models are always incomplete That s why they are called models!! Three issues, the solution, the problem domain, the interface Jackson claims that if you don t work on them separately, one or more could get lost. SOFT 423 Winter

27 Test 1 Review Test 1 Wednesday In Class SOFT 423 Winter

28 Test 1 Cover everything up until the end of today s lecture 30 minutes in length No lecture after test SOFT 423 Winter

29 Topics Various Definitions System Requirements System Interface Requirements vs. Design The Requirements Engineering Process Process Variability Data Modeling SOFT 423 Winter

30 Topics Elicitation in General Elicitation Techniques Interviews Background Reading Questionnaires Document Inspection Requirements Stripping SOFT 423 Winter

31 Topics Use Cases/Use Case Diagrams Scenarios Requirements Reuse Workshops and Brainstorming Requirements Analysis Requirements Documents SOFT 423 Winter

32 Next Class (Thursday) Data Modeling Structured Analysis and Data Flow SOFT 423 Winter