The Architecture of Systems
made and natural system is
characterized by a
structure and framework
that supports and/or enables the
of the system to
and perform missions.
This integrated framework is referred to as
the system’s architecture.
Architecture via a Construct
Let us introduce the concept of the
architecture via a construct
consisting of two key
the SYSTEM OF INTEREST (SOI)
its OPERATING ENVIRONMENT.
The SOI is composed of one or more MISSION
SYSTEM(s) (role) and a SUPPORT SYSTEM (role).
The OPERATING ENVIRONMENT consists of:
HIGHER ORDER SYSTEMS domain
A PHYSICAL ENVIRONMENT domain.
THE SYSTEM ARCHITECTURE
All natural and human
made systems exist within an
abstraction we refer to as the system’s OPERATING
Survival, for many systems within the OPERATING
ENVIRONMENT, ultimately depends on system
physical properties, characteristics,
strategies, tactics, security, timing, and luck.
The systems exhibit a common construct
that describes a system’s relationship to their
Top Level System Architecture Construct
When you analyze interactions of a SYSTEM OF INTEREST (SOI)
with its OPERATING ENVIRONMENT, two fundamental types of
interactions (i.e., vertical interactions under the
command and control of higher order systems)
2. Peer level interactions.
Important for three reasons:
First, the system elements enable us
classify, and bound system entity abstractions and their
interactions. That is, it is a way to differentiate
and what is not included in the system.
Second, the System Element Architecture
common framework for developing the
logical and physical
of each entity within the system
Third, the system elements serve as an initial starting
point for allocations of multi
Identification of system element classes
Top Level System Environment Construct
When a MISSION SYSTEM interacts with its OPERATING
1. Performs mission task assignments established by higher level,
command, decision authorities.
2. Interacts with
external systems (i.e., human
made systems, natural
environment, and its
induced operating environment during mission
THE SYSTEM ARCHITECTURE
When systems interact with their OPERATING
ENVIRONMENT, two types of behavior patterns emerge:
1. Systems interact with or respond to the dynamics
in their OPERATING ENVIRONMENT.
These interactions reflect peer
behavioral patterns such as
aggressor, predator, and
defender or combinations of these.
2. System Responses
behavior, products, by
and internal failures sometime result in
or catastrophic effects to the system
damage, degraded performance, for example
place the system’s mission or survival at risk.
Challenge in analyzing
The challenge in analyzing and solving system development
and engineering problems is being able to
organize, define, and articulate the relevant elements of a
initial conditions, assumptions, etc.) in
understand, intelligible manner that enables us
conceptualize and formulate the solution strategy.
Establishing a standard analytical framework
enables us to
apply “plug and chug” mathematical and scientific
principles, the core strength of engineering training, to the
architecture of the system.
UNDERSTANDING SYSTEM ELEMENT
interactions can be characterized by
two types of relationships:
Perhaps the best way to think of logical and physical
relationships is to focus on one topic
at a time and
then integrate the two concepts.
Identifying Logical Entity
first step in identifying logical entity relationships is to
simply recognize and acknowledge that
some form of
association exists through deductive reasoning.
Graphically, we depict these relationships as simply a line
between the two entities.
second step is to characterize the logical relationship
in terms of logical functions
occurs between them
must be provided to enable the two
associate with one another as
Logical Association Example:
Physical Entity Relationships
The physical implementation of system element interfaces
requires more in
depth analysis and decision making.
Typically, cost, schedule, technology, support, and risk
become key drivers that
must be “in balance” for the actual
Implementation as a
As we select components (copper wire, light switches,
lighting fixtures, etc.), we configure them into a system block
diagram (SBD) and electrical schematics that depict the
These diagrams become the basis for the