Systems Architecting

Systems 101

Background

What is a system?

Such a simple question has produced a plethora of definitions that span a spectrum from the most detailed to the incomprehensibly abstract. For the very specific definitions come out of a given domain and thus are laden with concepts particular to just them and they leave out notions that are relevant in other domains. On the other hand, the very abstract definitions looking to get a veneer of rigor using mathematical or formal languages are so difficult to comprehend that they really do not tell you much. Usually these abstract definitions then act a spring board for a whole framework of theoretical concepts, theorems, proofs and what have you. All this just gives one a headache in trying to figure out what the author is meaning to say. This is why there is so much confusion to explain a simple concept.

System defined

A system can be thought as the assembly of two or more items joined through a common interface where this assembly leads to properties that the individual items do not possess.

Systems are inherently emergent. Just take a look around and one can readily see how systems are composed and their emergent properties.

Examples:

Written communications 

characters ->words->sentences->paragraphs->chapters->books 

Transportation 

tires->axles->chasis->engine->fuel->steering wheel->automobile

Computation

transistor->cpu->memory->storage->input device->power->output device

Architect role

The architect develops the vision of the end system. He guides what elements need to come together and with what interfaces. This is done so that the emergent properties of the system solve the problem that the system is being built for in the first place.

This sounds simple for what an architect needs to do but in practice this can be amazingly complex. Usually, there needs to be technical complexities addressed, resource management, organizational dynamics and many times depending on the domain serious political aspects that need to be balanced.