1. Software Engineering in the Systems Context
Is SEMAT addressing the Root Causes of Complex IT Systems?
Harold “Bud” Lawson

2. Two Overlapping System Contexts
The Infrastructure Systems Context which enables Software Systems to be Developed, Operated and Maintained.
Hardware, Operating Systems, Middleware, Programming Languages-Compilers, Databases
The Application Environment Context
Enabling Systems, Cooperating Systems, Environmental Requirements and Influences

3. Infrastructure Systems
Continue to suffer from deep root cause problems in function distribution.
The System/360 ISA – OS and Systems Software Mismatch – March into the Black Hole of Complexity
The Estridge- Gates agreement giving Microsoft free license to drive the World Deeper into the Black Hole of Complexity. (Wintel cycle)
Finally – DARPA Clean Slate Program

4. Application Environment
Software Systems always exist in a wider Systems Environment
ISO/IEC (Identified Need for a System Standard)
ISO/IEC (Growing Utilization)
Narrow System of Interest, Wider System of Interest, Environment and Wider Environment
Enabling Systems, Cooperating Systems, Culture, History, Laws, Regulations, etc.
The System Context(s) adds many complexities
We need to “Think” and “Act” in terms of Systems
(Travel in the Systems Landscape)

5. Why do we create Man-Made Systems?
SYSTEM COUPLING DIAGRAM

6. We give names to these Systems
Project
Program
Task
Mission
Experiment
Natural
Man-Made
Mixed
(Thematic)
Facilities
Instruments
Theory
Knowledge
Methods
Tools
Processes
Thinking – “Understanding”
Acting – “Creating Solutions”

7. Balancing Architecture, Processes, Methods and Tools

8. Balance between Processes – Enterprise and Competence
Heroes

9. Some Relevant References
“Function Distribution in Computer System Architectures”, Invited paper appearing in the Proceedings of the Third Annual Symposium on Computer Architecture, Clearwater, Florida, January 1976.
“Philosophies for Engineering Computer Based Systems”, IEEE Computer, Vol. 23, No. 12, pp , December, 1990.
“Salvation from System Complexity”, IEEE Computer, Vol. 31, No. 2, Feb 1998, pp
“Infrastructure Risk Reduction”, Communications of the ACM, Vol. 40, No. 6, June 1998, pp120.
From Busyware to Stableware”, IEEE Computer, Vol. 31, No. 10, Oct 1998, pp
“Rebirth of the Computer Industry”. Communications fo the ACM June 2002/Vol. 45, No. 6.
“A Journey Through the Systems Landscape”, College Publications, Kings College, UK, ISBN

10. Personal Experiences of Architecture Driving Concepts
Pointer Variable (1964) based upon Linked Lists, Data Schema and Indirect Addressing
Flexible Central Processing Unit (1971) based upon Semaphore Variables, Asynchronism, High-Level Microcode and Language Boards
Control of High Voltage Power Dispatching (1974) based upon Monitors and Asynchronism
Automatic Train Control (1976) based upon Time Determinism, Software Circuits and Black-Board Memory
ISO/IEC (2002) based on System-of-Interest, Recursive Decomposition, Enabling Systems, Processes, Stages and Life Cycle Models