Complex Systems Engineering Strategies

Bob Marcus

robert.marcus@sri.com

Complex Systems Properties

• Emergent - Macroscopic dynamics and variables occur in the system, which is not easily predictable from local dynamics

• Multiscale Interactive - The macroscopic and component-level behavior interact in a measurable way

• Non-equilibrium – Large changes in the behavior of the system are possible under small perturbations

• Metastable - Long-lived non-equilibrium states can arise and be maintained in interaction with the environment

• Evolutionary Adaption- The system exhibits altered behavior in response to environmental changes

• Self Organizing - Coordinated behavior can take place among components without centralized guidance

Behavior Structures in Complex Systems

• Component = Basic element of functionality in the system. Intrinsic behavior under environment influences.

• Collaboration = Interactions without macroscopic coordinators. Behavior influenced by peer-to-peer interactions.

• Coordination = Interaction possibly managed by coordinators to support group goals. Behavior influenced by group dynamics.

• Control = Interactions directed hierarchically to foster global goals. Behavior constrained by controller.

•

• All of these structures can be present in a system of systems and can be mixed and combined recursively

Aspects and Examples of Behavior

Components Collaboration Coordination Control

No coupling Loose coupling Cooperative processes

Tight Coupling

Have dynamics and/or goals

Individual dynamics and goals (Nash)

Shared dynamics and goals (Pareto)

Global dynamics and goals (Managed)

Adapt to environment

Individuals adapt to each other

Individuals and coordinators adapt

Controllers adapt

Nodes in network Random Networks Social Networks Regular Networks (e.g. lattice)

Molecules in Chemistry

Gas Liquid Solid

Computers in Network

Peer-to-peer and Internet

Extranet Intranet

Components

Behavior Structures are Recursive

Controller

Components

Collaboration

Components

Coordination

Coordinators Controllers

Coordinators Controllers

ControllersCoordinators

Complex Systems Engineering Strategies

• Top down - Traditional systems engineering, Pre-defined coordination and interactions

• Bottom up – Self-organizing, Emergent collaboration and coordination from interactions.

• Matchmaking – Coordination is based on matching and combining existing components to meet requirements

• Middle Out – Coordination combines existing components and collaborations but also drives new requirements, collaborations and components

Note: Alternate strategies can be used in different stages of engineering

Top Down Design (Control-based)

Existing, Enhanced, Composite and possible new services and/or systems

USERS

Capability specifications (with priorities)

Capability description

Set of Services Needed

Set of Requirements

Requirements Analysis

User Requirements and Derived Requirements

Bottom Up Design (Collaboration-based)

Existing, Enhanced, Composite and possible new services and/or systems

USERS

Capability specifications and possible new capabilities

Capability description (with cost of implementation) and possible new capabilities

Capabilities available

Set of Services Available

Advertising

User Interfaces

Matchmaking ( SOA Orchestration)

Existing, Enhanced, Composite and possible new services and/or systems

USERS

Capability specifications (with priorities)

Capability description (with cost of implementation)

Set of Services

Set of Requirements

Matchmaking

User Requirements and Derived Requirements

Middle Out Design (Coordination-based)

Existing, Enhanced, Composite and possible new services and/or systems

USERS

Capability specifications (with priorities) and possible new capabilities

Capability description (with cost of implementation) and possible new capabilities

New capabilities available

New capabilities needed

Set of Services

Set of Requirements

Mediating

User Requirements and Derived Requirements

Trial Run

JPMO

FDCE Vendors

Open SourceLibraries

StandardsBodies

Contractors

Consumers Producers

MikeHebert(JPMO) Bob

Marcus(NCOIC)

Needs

Offerings

(1) (2)

(3)

(4)

NECC ST&TMarketplace

(5)(6)

(7)

(8)

(3)

(7)

(9)

JMPO, FDCE groups solicited for ST&T needs

Needs consolidated, prioritized and binned

Needs sent to Bob Marcus

Clarify need

Matchneeds with offerings

Gain producers

interest

Develop list of offerings – use Industry Days as delivery mechanism

Scrub list of offerings and do final offering selections,

finalize schedules for Industry Day(s)

Ensure Industry Day(s) meet needs and

ensure participation