What is Software Engineering?

May 21, 2010

This post is a follow-up to my earlier blog on Software Certification. Certification is a complex topic.  Before getting too far into a discussion on certification, let’s look at the work we call software development.

World wide there are millions of individuals who develop software for a living and they go by many names: programmer, software developer, software craftsman and software engineer.

From a work content point of view, the work of software development appears similar to the work that engineers perform and there is a recent trend to call individuals who develop software, Software Engineers.

For the past 20 years, I have been a consultant to dozens of companies assisting them improve their business processes and improve their ability to develop software. During this time, I have taught Software Engineering as an adjunct at DePaul University in Chicago.  This past Winter Quarter, I taught a Software Engineering Process class with a focus on Agile and Lean software engineering.  After this class I felt that my old definition of Software Engineering was inadequate and felt the necessity to develop the current definition as follows:

Larry’s Current Definition of Software Engineering

“Software Engineering is a profession that uses sound engineering principles, processes and practices and a body of knowledge to propose, design, develop, deploy, operate, maintain and retire computer software solutions over their useful life that people will buy and use to solve real world problems.”

Within this definition the Software Engineer becomes responsible for the overall software solution from the initial idea through design, development, deployment, operation to retirement.

This definition also accommodates the various sub-specialties of Software Engineering that we see in practice today such as: Business Analyst, Data Base Engineer, Infrastructure Engineer, Network Engineer, Software Developer and Systems Administrator.

Why develop my own definition of Software Engineering?

For the last 20 years I had been using a definition of Software Engineering by Fritz Bauer from 1968 (see below).  That definition was workable for a long time, but recently I felt that that it needed to be broadened to better encompass the full software development life cycle.

Before I wrote my own definition of software engineering, I researched several other definitions: one on Wikipedia and one defined in IEEE’s Software Engineering Body of Knowledge (see below). Neither of these definitions satisfied by current view of software engineering in terms of the breadth or depth required to “engineer” software in the real world situations that I saw every day in my consulting work.

Software development is a complex process.  The software development process begins with an idea, continues with the design and development of a solution followed by operating the solution in production for a period of time and eventually retiring the solution as described below:

  • Envision: The “engineering” of a software program begins when an individual, often called the “user” determines they have a need for something new or a “developer” envisions a new way to solve a problem.
  • Propose: The “engineering” continues with a proposal to obtain funding for a project to develop the solution.
  • Design: Once funding is obtained, “engineering” designs a solution to the problem.

  • Development: Next, “engineering” develops a working version of the solution.
  • Deploy: Once an initial version of the system has been developed, further “engineering” is usually needed to successfully deploy the solution into operation.
  • Operation and Maintenance: As the solution operates and its use grows, there is a need to “engineer” refinements into the solution for it to continue to grow and satisfy changing conditions.
  • Retirement: Eventually, the solution can not be cost effectively refined and it must be replaced by a “new” solution and the cycle continues.  Even in this stage, there is a need to “engineer” the graceful retirement of the “old” solution.

Although this may seem like a linear life cycle, there is usually considerable iteration between the various stages.  Throughout this life cycle, there is a need for a “software engineer” to formally or informally make use of a wide variety of principles, processes, and practices such as:  requirements definition (or product backlog development), coding and coding standards, configuration management, testing and a mechanism of handling changes (Change Control or Iterations) to name a few.

Other Definitions of Software Engineering

Fritz Bauer’s Early Definition of Software Engineering

“The establishment and use of sound engineering principles in order to obtain economically software that is reliable and works efficiently on real machines.”

Fritz Bauer, 1968

Wikipedia

Software engineering is a profession and field of study dedicated to designing, implementing, and modifying software so that it is of higher quality, more affordable, maintainable, and faster to build.

See http://en.wikipedia.org/wiki/Software_engineering for more details.

IEEE Computer Society

The IEEE Computer Society‘s Software Engineering Body of Knowledge defines “software engineering” as the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software, and the study of these approaches; that is, the application of engineering to software.[6]

See http://www.computer.org/portal/web/swebok/html/ch1#Ref1 for more details.

Although the Wikipedia definition mentions design of software, it does not focus on the full life cycle and adds constraints such as “more affordable” that are extraneous.  The IEEE SWBOK definition includes operation in the life cycle, but does not mention design.  It also adds a statement around “quantifiable” which often can not be accomplished in the real world.

More posts on this topic in the future!


Software Certifications

April 29, 2010

At the APLN Chicago meeting on Thurs, April 21, 2010 we had a good discussion on Certification and Certificates. The discussion focused on the reasons for and against certification as follows:

Reasons for Certification:

1)      As guide to learn a domain

2)      To get past hiring filters

3)      To demonstration that the individual has learned a domain

4)      To socialize with peers w/similar knowledge, challenges and interests

Reasons against Certifications:

1)      Doesn’t show true capability – especially when Certification occurs after a 2 day class without a test (or even 1 week class with a test – I’m thinking of PMI here);

2)      Certification turns skills, knowledge, experience and knowledge work in general into a commodity

Some of my thoughts on the issue that were not discussed at the APLN meeting:

I believe that Certification has turned knowledge work into a commodity without adequate proof that it can be turned into a commodity.  The use of Certifications for positions like Project Manager, Tester, Business Analyst and Scrum Master has made the life of a hiring official easier, but I doubt that it has improved the quality of the workers hired.

Certification is not the way to solve the problem, especially when Certification means attending a 2-day class (or even attending a 1-week class and test).  Pretending that a Certification will fix the personnel selection problem is foolish and dangerous.

Where’s the Beef?

I would like to see a hiring official show me defensible personnel selection data that shows that Certifications has improved the quality of the work force hired.

In fact, I believe that Certification in the Computer Industry has led to the outsourcing of many US jobs to cheap foreign labor without adequate demonstration that the foreign labor can in fact deliver the same results.

Assessing Talent is difficult.  It is difficult in the software development area and it is difficult in sports teams as well, as most fans of Chicago area teams know.

Interview based personnel selection systems (which most organizations use) have low validity with correlation coefficients between 0.20 and 0.30. This means that the interview based selection systems account for between 4% and 9% of the variability between interview ratings and job success.  Not a number you would want to “bet the farm on”!

Improved interviewing skills, job simulations and greater focus on grooming internal employees will provide some improvement, but current personnel selection techniques are just not very effective.

It takes many years of continued demonstration of good skills, knowledge and experience in real life situations to become a licensed Medical Doctor.  If we want to formally assess talent, than we should State License Software Engineers in a way similar to the Medical Profession!


Software Engineering

April 25, 2010

I have been consulting in IT for over 30 years and have been teaching Software Engineering at the graduate level for most of the same time.

During that time I have noticed a disturbing trend among the individuals I meet within the IT Industry.  Many individuals only have a narrow knowledge of some specialty within IT.  They may know a specific software language such as:  C#, Pearl, PHP or Python; they may know a specific operating system such as: Linux or MS/Windows Vista; or a specific software development methodology such as:  Waterfall, RUP or Scrum, but do not have a broad range of skills.

This lack of overall knowledge of the entire software development, operation and maintenance process often leads to micro-optimization, inappropriate solutions and failed projects.

In other professions such as medicine, an doctor in training in addition to needing a college degree, and a medical degree needs to practice his trade as an itern to learn the general practice of medicine before they learn a specialty.   Learning a specialty takes years more of learning and practice.  Among the trades such as Electrician, Plumber or Carpenter, there is a requirement to learn the general trade over an extended period as a Journeyman before learning a specialty.

Not so in the IT profession.  Individuals in IT often learn a specialty, begin work  and never learn the general principles and practices of software development, operations and maintenance.

Computer software is becoming more complex and integrated with the business organization.  As a result, there is a need to identify individuals who have a broad range of expertise, look at the overall problem and develop a comprehensive solution to that problem.  These individuals should be called: Software Engineers. They should be taught the broad based of knowledge necessary to develop, operate and maintain software solutions.  Then they need to learn to practice software engineering over an extended period of time.  Once this is done, they can focus on a specialty and become certified in that specialty.

I try to correct this lack of general knowledge by teaching Software Engineering at the Graduate Level, but I can not reach every individual going into IT. We need focus on teaching Software Engineers if IT is every to become a true profession.