Dec 6, 2012

The Ten Qualities of Good Requirements

A solid database design provides a firm and extensible base an organisation’s data.  A well-architected solution brings with it a sense of integrity and elegance that allows systems to be extended easily, and yet retain its integrity.

If any of these are badly done, the resulting solution is flaky, troublesome, and a menace to update.

But bad requirements are even worse, for they are our map to what should be built.  If the requirement is wrong, the solution built is wrong.  If the requirement has gaps, then the solution will have gaps.  If the requirement is misunderstood, then the solution is wrong.

There is an art to producing requirements.

1. Requirements Must Have an Owner

2. Requirements Must be Singular

3. Requirements Must be On the System and Not the Operator

4. Requirements Must be Unambiguous

5. Requirements Must Not Specify the Solution

6. Requirements Must have a Rationale

7. Requirements Must be Tied to the Concept of Operations

8. Requirements Must be Justified

9. Requirements Must be Prioritised

10. Requirements Must be Contextualised

Dec 5, 2012

Comparing the BABOK and the SEBOK, Part 5

I want to take a second look at the Knowledge Areas identified by the BABOK and those by the SEBOK, specifically where there is an overlap between the two sets. 

I want to do this in preparation for a deeper comparison of their treatments of their Knowledge Areas and Tasks and Activities.

The table below lists the Knowledge Areas for the BABOK, and what to me might be the corresponding Knowledge Area addressed in the SEBOK.  As can be immediately seen, the SEBOK Knowledge Areas cover a lot more topics.

BABOK Knowledge Area SEBOK Knowledge Area Remarks
  Systems Fundamentals  
  Systems Science  
  Representing Systems with Models  
  Systems Approach Applied to Engineered Systems  
 

Life Cycle Models

 
 

System Deployment and Use

 
 

Product and Service Life Management

 
 

Systems Engineering Standard

 

Business Analysis Planning and Monitoring

 

 

Elicitation

Concept Definition

This SEBOK KA contains the following Activities:
  • Mission Analysis
  • Stakeholder Needs and Requirements

Requirements Management and Communication

System Definition

Systems Engineering Management

“Requirements Management” is very briefly treated in the SEBOK under the “System Requirements” topic, which is under the System Definition KA.

Configuration Management is considered part of the BABOK KA “Requirements Management and Communication”. In the SEBOK, Configuration Management is discussed under the Systems Engineering Management KA

Enterprise Analysis

Concept Definition

This SEBOK KA contains the following Activities:
  • Mission Analysis
  • Stakeholder Needs and Requirements

Requirements Analysis

System Definition

The topic of "System Requirements” addresses assessing the quality of the requirements and their prioritisation. System Requirements is a topic under the KA System System Definition

Solution Assessment and Validation

System Realization

This SEBOK KA contains the following Activities:
  • System Implementation
  • System Integration
  • System Verification
  • System Validation
 

Product Systems Engineering

 
 

Service Systems Engineering

 
 

Enterprise Systems Engineering

 
 

System of Systems

 
 

Enabling Businesses and Enterprises

 
 

Enabling Teams

 

Underlying Competencies

Systems Thinking

Enabling Individuals

 
 

Systems Engineering and Software Engineering

 
 

Systems Engineering and Project Management

 
 

Systems Engineering and Industrial Engineering

 
 

Systems Engineering and Procurement / Acquisition

 
 

Systems Engineering and Specialty Engineering

 

In the next post on this topic, I will start comparing the contents of the matching Knowledge Areas.

Dec 4, 2012

Comparing the BABOK and the SEBOK, Part 4

In this post I’ll compare how the two documents structure their presentation of a Knowledge Area (KA).

BABOK Knowledge Area Structure

The BABOK discusses each of its KA in turn.  The discussion starts with a short overview of the KA,  followed by an Input / Output Diagram showing the Tasks under that KA, the Inputs required by the Tasks, and the Outputs generated by the Tasks (and by extension the KA).

The core of the Knowledge Area is its Tasks, and the BABOK structures the presentation of the KA around the Tasks.  Each Tasks is described in turn using the following sections:

  1. Purpose of the Task – brief explanation of the focus of the Task.
  2. Description – usually more details about the Task.
  3. Input – a list of information (typically documents) needed for performing the Task, also describing why each Input is used for.  This section is accompanied by a context diagram showing the Task, the Inputs it requires, the Task Outputs, and downstream Tasks using the Outputs as Inputs.
  4. Elements – describes considerations relevant to the Task which need to be addressed for a successful execution of the Task.
  5. Techniques – lists the most common techniques used in performing the task.  Techniques are methods or tools such as ‘Interviewing’, or ‘Brainstorming’.  All of the Techniques are described in more detail in Chapter 9, so this section is just a listing.
  6. Stakeholders – is a list of organisation titles generally involved or interested in the Task execution.
  7. Output – a list of the Outputs of the Task (generally documents).

SEBOK Knowledge Area Structure

As we have seen in the previous post, the SEBOK has many more KA’s than the BABOK.  Not only are there many more, the scope is more extensive.  Whereas the BABOK KA’s are narrow enough that one can expect every practicing BA to be knowledgeable at a professional level in ALL the KA’s (though perhaps not all the Techniques), the SEBOK KA’s are so expansive, it is unlikely that a majority of professional SEs would have high quality proficiency in all the SEBOK KAs.

Each KA is divided into Topics (contrast with ‘Tasks’ for the BABOK), which confusingly is also called ‘Activities’.  The KA itself is described in great detail (far greater than what is done in the BABOK).  After which a list of Reference work is provided.

After providing a detailed discussion of the KA, each of the Activities under that KA are discussed using the following structure:

  1. Introduction – brief narrative about the Topic 
  2. Purpose and Definition – detailed description of the Topic / Activity
  3. Principles and Concepts - key concepts one needs to know about the Topic.  Depending on the topic being discussed, this can be fairly comprehensive.
  4. Process Approach / Activities of the Process – description of the subtasks performed for the Activity
  5. Artifacts – listing of most common outputs (generally documents) for the Activity
  6. Methods and Modeling Techniques – listing and description of key Techniques one can expect to be used to perform this Activity.  (For the most part, the SEBOK uses the single-ell spelling ‘modeling’, but sometimes also uses ‘modelling’)‘
  7. Practical Considerations – tips and lessons learned from the trenches.  
  8. References – comprehensive list of Works Cited, Primary References, and Additional References relevant to the Activity.  Since the SEBOK is merely a 'Guide’ to the Body of Knowledge, this References section makes eminent sense – it points to where the reader can go to get more of the Knowledge.

Comparison of the Structures

The table below compares the KA presentation structure of the two BOKs

BABOK SEBOK Remarks
Overview Introduction Neither of these sections are titled as such.  Both sections are untitled narratives.
Purpose of the Task Purpose and Definition  
Description Purpose and Definition  
Input   It is very surprising that SEBOK seems to have no equivalent section
Elements Principles and Concepts
Practical Considerations
 
  Process Approach / Activities of the Process The BABOK has no equivalent
Techniques Methods and Modeling Techniques  
Stakeholders   The SEBOK has no equivalent section
Output Artifacts  
  References The BABOK references are all collected at the end of the Guide, where it is far less useful for someone wanting to know more about a specific Task.