Impacts of SoS on
Software Development
USC CSSE Workshop
Integrating Systems and Software Engineering
October 29, 2007
Gary Hafen
Corporate Fellow,
Software Engineering
Situation
• Software is providing an increasing
percentage of functionality in our
systems
– Space Craft
– Aircraft
– Ships
– Automobiles
– Cell Phones
– Etc.
Situation
• Systems are being networked to
achieve capabilities beyond what
individual systems alone can provide
– System of Systems
– Family of Systems
– Global Information Grid
– Communities of Interest
Ramification
• Monolithic System design methods
and techniques won’t scale up to an
asynchronous, loosely coupled, multinode, system of systems
– Does not hierarchically
decompose functionally
– Manage and minimize
constraints vs. variables
– Adaptive vs. conformal
interface logic
Monolithic System Design
• Defined and Contained Scope of Function
• Centralized control
– Can design with hierarchical structure
• Deterministic Behavior
– Desirable characteristic that is verified and validated
• Planned Evolution
– Controlled centrally
Traditional Acquisition Process Works
For These Systems
SoS Design
• Initially Defined Scope of Function
– Not all requirements can be known
• Decentralized control of internal and external
interfaces
– Architecture must be adaptive to uncontrolled
interface changes
• Behavior Emerges
– Cannot perform traditional Verification
– Emerging behavior may be good or bad
depending on objectives and constraints
• SoS Evolution is not controlled by a central authority
– It Happens
Impact on Software - 1
• Software Requirements Allocation is problematic
– All requirements are not known
– Software solutions must balance performance
versus adaptability/flexibility
– Functionality may need to be migrated between nonheterogeneous systems
– Interfaces cannot be assured to be consistent or
even present
• Functionality must adapt to external environment
• Creates a wider range of test conditions
Requirements Growth/Instability is a Traditional
Software Risk
Impact on Software - 2
• Software Architecture Technologies
– Standards such as DoDAF, SoA, XML,
CORBA are necessary
– Adaptive, intelligent network awareness
characteristics are now required
– Exploitation of Expert Agent and Data Mining
Technologies to achieve capability
– Polymorphic Computing Architectures
– Fault Containment/Tolerance to unplanned
external stimulus
Non-Determinism is Now an Asset
Impact on Software - 3
• Implementation Technologies
– Model Based Development
– Auto-generation of code, test vectors
– 4th or 5th generation languages
– Intelligent System composition tools
– Performance and Quality of Service assurance
Impact on Software - 4
• Test/Verification/Validation
– Non-deterministic functional operation
– Uncontrolled Test Environment
– Isolation of errors in shared SoS architecture space
– Intelligent System validation
• Software Assurance
– Multiple Independent Levels of Security
– Information Assurance in an Information Warfare
environment
– Cyber Attack
Summary
• A System of Systems cannot be defined, designed,
developed, verified and validated by conventional
system development processes
• What used to be considered design “gold plating”
may now be mainstream thinking
• Controlling functional performance to a confined
envelope of conditions is no longer feasible
– Emergent behavior has to be evaluated as desirable
or undesirable
– Adaptive characteristics need to be included in
requirements allocation
• With the lack of controlled behavior, continuous
Software Assurance becomes a focused priority.