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Title: UbiCom Book Slides


1
UbiCom Book Slides
  • Chapter 10
  • Autonomous Systems Artificial Life
  • (All Parts, Short Version)

Stefan Poslad http//www.eecs.qmul.ac.uk/people/st
efan/ubicom
2
Chapter 10 Overview
  • Chapter 10 focuses on
  • Internal system properties autonomous
  • External interaction with any type of environment
  • Focussing more on physical environment
  • A lesser extent focussing on Human ICT
    environments

3
Introduction
4
Related Chapter Links
  • Sometimes autonomy is seen as a property of
    intelligence (Chapter 8)
  • Designing UbiCom systems to be autonomous enables
    them to be self-managed (chapter 12)

5
Chapter 10 Overview
  • The slides for this chapter are split into
    several parts
  • Part A Autonomous Systems Basics ?
  • Part B Reflective Self-Aware Systems
  • Part C Self-Management Autonomic Computing
  • Part D Complex Systems
  • Part E Artificial Life

6
(No Transcript)
7
Part A Outline
  • Basics ?
  • Types of Autonomous System
  • Autonomous Intelligent Systems
  • Limitation of Autonomous Systems
  • Self- Properties of Intra-Action

8
Introduction
  • Term autonomous originates from the Greek terms
    autos meaning self and nomos meaning rule or law.
  • Autonomy is considered to be a core property of
    UbiCom systems
  • enabling systems to operate independently
  • without external intervention.
  • Autonomous systems operate at the opposite end of
    the spectrum to completely manual, interactive,
    HCI systems.
  • Without autonomous systems, sheer number
    variety of tasks in an advanced technological
    society that require human interaction would
    overwhelm us and make system operation
    unmanageable.

9
Automatic System
  • An automatic system is specific type of
    autonomous system designed to
  • Act without human intervention
  • Execute specific preset processes
  • Work in deterministic dynamic environments
  • Incorporate simple models of environment
    behaviour
  • Incorporate algorithms to control the environment
    (closed-loop control systems).

10
Autonomous Systems
  • More general types of systems than automatic
    systems are needed. Why?

11
Autonomous Systems Design
  • 4 major designs for general autonomous systems
  • Dynamically reusable and extensible components
  • EDA and context-aware system
  • Hybrid goal-based (Section 8.3.4) and environment
    model based IS systems (section 8.3.3).
  • Autonomic Systems

12
Autonomous Systems Design Component-based
  • Autonomous systems can be designed to consist of
    dynamically reusable and extensible components
  • There are different types of component autonomy /
    cohesion
  • Design autonomy
  • Interface Autonomy
  • Components use of SOA (Section 3.2.4).
  • Component functions could be reprogrammable
    e.g., using mobile code (Section 4.2.2).
  • These types of systems tend to have a strong
    notion of ICT environment autonomy
  • but not of their physical human environment
    autonomy.

13
Autonomous Systems Design EDA, Context-Aware
  • Autonomous systems which operate in dynamic
    environments can be designed to ?
  • These systems tend to focus on
  • Physical world awareness and user awareness
  • How the system decides how to adapt to such
    context changes how they affect current,
    active, user goals (Section 7.2).

14
Autonomous Systems Design IS
  • Autonomous systems can be designed to be hybrid
    goal-based (Section 8.3.4) and environment model
    based IS systems (section 8.3.3).
  • Generally, focus of such systems is on
    supporting a notion of social autonomy or
    self-interested behaviour rather than on
    supporting ICT environment autonomy or physical
    environment autonomy.

15
Autonomous Systems Design Autonomic
  • Autonomous systems can be designed to be
    autonomic. How?
  • Key challenges?

16
Autonomous Intelligent Systems
  • Autonomy is a key property of an IS
  • An IS may have a physical embodiment or software
    embodiment which may be free to be executed in
    any part of a internetworked virtual computer.

17
Autonomous Types Self Governance
  • There are two main kinds of autonomy
  • self-governance
  • independence.

18
Social / Organisational Autonomy
  • Often an IS will delegate actions to another one,
    making it dependent on actions of another IS
  • But ? risk of failure for the delegated actions
    because of misunderstandings, disagreements and
    conflicts, error, unknown private utilities and
    self-interests may operate.
  • Designs for IS to cope with risk of delegation of
    actions?

19
Autonomous versus Automatic
  • Automatic refers to a system being self-steering
  • To be self-steering requires a system to sense
    its environment act upon it based upon what it
    has sensed
  • Autonomous are generally first automatic systems
    but which are extended so that they become
    self-governed.

20
Limitation of Autonomous Systems
  • Systems designed to be autonomous over parts of
    its life-cycle
  • Challenges in supporting full autonomy?

21
Self- Properties of Intra-Action
  • Application processes are not influenced by
    external behaviour or control but are dependent
    on, or driven by, their internal behaviour
  • Attempts to externally pertubate the system will
    be resisted and moderated in autonomous systems.
  • Some system behaviour is decentralised and local,
  • However, other system behaviour is
    community-wide, global
  • Set of so called self- properties is a way to
    characterise autonomous systems
  • These are also called the self-self-x or auto-
    properties
  • Set of self- properties that need to be
    supported depends upon the application domain and
    system design.

22
Self-Star Properties
  • Need to model complex systems whose components
    have some autonomy and propensity to maintain and
    improve their own operation in the face of
    external environment perturbations, e.g.,
  • Autonomic computing
  • Organic Computing
  • IS

23
Self-Star Properties
  • Self-star model focuses on doing things
    self-contained or doing things internally
  • List of types of self-star system could be
    expanded
  • to incorporate self-referencing, self-interaction
    (intranets) etc.

24
Self-star Properties Examples
  • Self-Configuring
  • Self-Regulating
  • Self-Optimising, Self-Tuning
  • Self-Learning
  • Self-Healing, Self-Recovery
  • Self-Protecting
  • Self-Aware
  • Self-Inspection Self-Decision
  • Self-Interested
  • Self-Organising
  • Self-Creating, Self-Assembly, Self-Replicating
  • Self-Evolution, Emergence
  • Self-Managing or self-governing
  • Self-Describing Self-Explaining
  • Self-representing

25
Part B Outline
  • Self-Awareness ?
  • Self-Describing and Self-Explaining Systems
  • Self-Modifying Systems based upon Reflective
    Computation

26
Context-Awareness versus Self-Awareness
  • Context-awareness is complementary to
    self-awareness.
  • Context-awareness (Section 7) focuses on an
    awareness of a systems external environment
    (user, ICT, Physical ) context, periodically
    sensing this, automatically detecting significant
    change, and using this to adapt the internal
    systems behaviour to external environment
    behaviour.
  • An associated design issue is what degree if any,
    an awareness the system needs of its own internal
    behaviour.
  • Self-awareness focuses on monitoring its internal
    behaviour in order to optimise its behaviour

27
Self-Awareness
  • Basic design is that an ICT system does not
    process itself or is not aware of its own
    actions. Why not?
  • Is basic designs for Intelligent Systems
    inherently self-aware?
  • Useful that systems know its internal state how
    it acts?

28
Self-Awareness Applications
  • Optimising internal resource use
  • Robots, e.g., robot arms
  • Self-explaining systems

29
External Descriptions Explanations
  • Common reasons why systems are less usable?
  • Intelligibility to user etc
  • Disadvantages to using an external operators
    manual?
  • How to support self-descriptions?
  • Using internal (to the device) resources
  • Hybrid device can be queried for the address,
    e.g., URL, of its description, but which resides
    elsewhere in its environment, e.g., the Cooltown
    and Semacode, Tagging (Chapter 6)

30
Self-Describing Self-Explaining Systems
  • A self-describing system is able to describe
    itself from the perspective of what
  • A self-explaining system describes itself from
    the perspective of how and why.
  • Self-descriptions self-explanations can be
    supported at multi-levels
  • Systems can also provide mechanisms and
    interfaces to output their external for other
    meta-level processes or diagnostics
  • e.g., the JTAG interface (Section 6.6.1).
  • Devices know their state in relation to their
    plans and goals
  • etc

31
Self-Description Limitations Design Issues
  • Limitations?
  • Design issues?
  • How rich are descriptions?
  • How structured are they?
  • How full versus short?
  • Internal versus external and on-line versus
    off-line,
  • Co-located versus external not co-located
    (Section 6.2).

32
Reflection
  • Reflection is the process by which a system can
    observe its own structure and behaviour, reason
    about these and possibly modify these
  • Reflection has several benefits for UbiCom?
  • Reflection is considered in more detail in
    Section 10.3.3.

33
Reflective System Architecture
To support reflection, reflective computation is
done by a system at a meta-level about its own
operation at the application or base level of the
system
34
Reflection
  • There are three elements to the reflection
    process
  • Instrumentation
  • introspection
  • adaptation

35
Reflection Design
  • Combined system reflection operation
    representation
  • Separate system reflection operation
    representation
  • Design issues?
  • How to support enable this meta-level
    processing
  • How the reflection is represented,
  • what triggers the reflection
  • what parts of the system can be reflected upon
  • performance security aspects of using
    reflection.

36
Reflection Design
  • Reflection as an extension to middleware model?
  • Reflective model is often applied as a design for
    context-aware systems. How?

37
Part C Outline
  • Basics ?
  • Self- Management Control
  • Autonomic Computing Design
  • Autonomic Computing Applications
  • Modelling and Management Self-Star Systems

38
Autonomic Computing
  • Motivation for autonomic systems was to deal with
    the obstacle of IT system complexity
  • The growing complexity of the IT infrastructure
    threatens to undermine the very benefits
    information technology aims to provide (Horn,
    2001).
  • Autonomic computing is one of the most well-known
    types of self- system
  • Autonomic computing is also referred to as
    self-managing systems or self-governing systems.
  • Autonomic computing was inspired through analogy
    with the human bodys nervous system.
  • Autonomic systems can be constructed as group of
    locally interacting autonomous entities that
    cooperate to maintain system wide behaviour
    without any external control.

39
Types of Self- Control Compared
Global
Global
Policies
Policies
Policies
Policies
Control Loop
Local
Local
Policies
Local
Policies
Local
Local
Local
Local
Local
40
Key Autonomic Computing Properties
  • Different definitions of key properties
  • Keplar
  • self-configuration
  • self-optimisation
  • self-healing
  • self-protection.
  • Ganek
  • self-awareness
  • context-aware adaptation
  • planning to control behaviours constrained by
    system policies.

41
Taxonomy for Basic Self-star Properties
  • General Classification for basic self-star
    properties of systems can be based upon?

42
Taxonomy for Basic Self-star Properties
  • Hence, agent designs oriented to these
    environments can form the basis of designs of
    autonomic systems
  • Specific properties relate to the type of
    organisation
  • Spatially dependent,
  • Role-based,
  • Group-based,
  • Resource access control
  • Self protecting.

43
Taxonomy for Basic Self-star Properties
  • Methods for coordination of autonomous systems
    are dependent on the type of organisation
  • Tuning servers individually (also called locally
    or on a microscopic scale) may be beneficial
  • However in other applications, tuning servers
    individually, may not be optimal

44
Autonomic Computing Design
45
Autonomic Computing Architectural Models
  • 5 basic components
  • a user interface (task manager)
  • an autonomic manager with an autonomic control
    loop
  • a knowledge base about the managed resources
    including management policies
  • a standardised interface to access managed
    resources (TouchPoint)
  • service-based communications network, the ESB
    (Section 3.3.3.8).

46
Designs to Support Self- System Components
  • SNMP and the MIB can be used to implement
    TouchPoint part of knowledgebase (Chapter 12)
  • Semantic and Syntactical metadata wrappers can be
    used to describe the structures of resources in
    richer ways.
  • Sensors can poll resources or receive
    notifications about events in resources (Chapters
    3,6)
  • Designs for autonomic control loop can be based
    on
  • feedback control algorithms (Section 6.6)
  • action selection loop design of intelligent
    systems (Section 8.3).

47
Designs for Self- System
48
Different Levels of Support for Self- Properties
  • Self-star systems can be designed to support
    different maturity levels of self-star
    properties
  • Basic
  • Managed
  • Predictive
  • Adaptive
  • Autonomic

49
Autonomic Computing Applications
  • Channels allocation to meet peak demand for calls
    in different mobile phone cells
  • Load-balancing in servers to meet a designated
    QoS under variable external processor loads
  • Intrusion detection
  • Protecting Critical Infrastructures (SCADA)

50
Modelling Managing Self- Systems
  • How to model and mange systems which are dynamic
    decentralised and to an extent,
    non-deterministic?
  • Unit testing and formal proofs?
  • Statistical methods?
  • Equation based computation methods ?
  • Equation free computation methods ?
  • Time series chaos theory analysis?

51
Modelling Self- Systems
  • Modelling behaviour interaction in simple
    life-forms forms an important contribution to
    improve models of complexity.
  • Mathematical equations nay not capture many of
    natures most essential mechanisms.
  • Modelling systems purely based upon physics
    interaction may lead to useful self-organising
    system models, models
  • They must take into account higher level social
    science interaction models

52
Part D Outline
  • Basics of Complex Systems ?
  • Self-Organisation and Interaction
  • Self-Creation
  • Self-Replication

53
Complex Systems
  • Complex system is defined to be a system whose
    properties are not fully explained by an
    understanding of its component parts
  • In computation, a complex system often represents
    a hard-problem that cannot be solved within
    polynomial time.
  • Complex ubiquitous systems?

54
Complex Systems
  • Complex systems can arise when?
  • Complexity can also arise through, or can be
    designed using, simple interactions and repeated
    applications of simple rules

55
Modelling Complex Systems
  • It is not clear how accurate or equivalent the
    complexity models of one phenomenon,
  • Models of relative complexity?
  • Modus also discusses the growth in complexity

56
Modelling Complex Systems
  • Conventional technique to modelling complex
    systems is the divide-and-conquer or reductionist
    approach
  • Some systems however, have macro properties which
    are almost impossible to predict from knowledge
    of the micro level properties of the individual
    parts of the system

57
Modelling Complex Systems
  • Key design challenges is whether or not complex
    system that are designed by
  • specifying local interactions
  • can be controlled, constrained
  • can be coherent
  • Can they enable the separate lower level
    components to act at a higher level in some
    unified way?

58
Self-Organisation and Interaction
  • Self-Organisation is a set of dynamical processes
    whereby stable or transient structures or order
    appears at a higher or global level of a system
    from the interactions between the lower-level or
    local entities
  • Self-organised behaviour can be characterised by
    key properties such as
  • Spatiotemporal structures
  • Multiple equilibria
  • Bifurcations

59
Emergent versus Self-Organising Systems
  • Emergent or process of macro behaviour emerging
    from micro or local behaviour is also called
    micro-macro effect.
  • Self-organisation is an adaptable behaviour that
    autonomously acquires and maintains an increased
    order, statistical complexity, structure, etc.
  • Emergence can have a micro-macro effect, but may
    not be self-organising, hence
  • System can have emergence without
    self-organising.
  • System can also be self-organising without
    emergence.
  • Self-organising Emergent are often combined

60
Self-Organising Systems Interaction Mechanisms
  • Interaction mechanisms organising and
    coordinating autonomic system components?
  • Digital Stigmergy
  • Co-field coordination (or Gradient-based
    Coordination)
  • Tag-based,
  • Token-based

61
Digital Stigmergy Design Principles
  • Proximity principle
  • Quality principle
  • Diverse response
  • Stability principle
  • Adaptability principle
  • UbiCom Applications
  • Network routing
  • Power distribution energy regulation system etc

62
Co-field Coordination
  • Inspired by physics forces in nature
  • Also called Gradient-based Coordination and Wave
    Propagation coordination
  • Autonomous entities can spread out a computation
    field or co-field, throughout the local
    environment
  • UbiCom Applications
  • to provide context information to other entities
    to follow the field.
  • to signal that someone wants priority use of
    specific resources.
  • to repel (separation) or attract individuals
    (cohesion and alignment).
  • to support tourists in planning their activities

63
Tag based Coordination
  • Observable labels are attached to things.
  • Can be used to make control decisions, to allow
    self-organisation of things according to tag
    types.
  • UbiCom Applications
  • Resource allocation in networks to enable them to
    adapt to continuous node failure and to the
    addition of new nodes and resources and changes
    in traffic conditions (Section 11.8.1).

64
Token based Coordination
  • Token based coordination resource access control
    token can be circulated amongst resource users
  • Section 11. 8.1
  • Token based vs. Tag based coordination?
  • Applications
  • to control access to shared things such as
    devices or people in social spaces, e.g., patient
    appointment system

65
IS Models as Self-Organising Systems
  • MAS can support relatively fixed organisational
    models based upon quite complex agents and
    relatively complex cooperative and competitive
    interaction
  • But these often lack the flexibility to
    dynamically reorganise and to self-organise?
  • Cellular computing
  • Amorphous computers

66
Self-Creation and Self-Replication
  • Self-organising models discussed so far focus on
    how existing peers and resources are optimised
    through self-organisation, not clear how
  • Self-replication is considered to be a hallmark
    of living systems.
  • Evolution of self-producing systems require
    strategies that lead to cumulative selection of
    traits occurs over multiple cycles of
    reproduction

67
Self-Replication Computer Viruses
  • Computer virus is a well-known examples of
    artificial self-replicating mechanism.
  • Computer virus is also referred to as a
    self-reproducing or self-replicating program
    (SRP).
  • Tends to be software virus rather than a hardware
    virus. Why?
  • Are nano devices more dangerous than Micro size
    MEMS as hardware viruses?

68
Self-Replication Computer Viruses
  • Virus is often introduced into host system
    hidden
  • Virus contains a trigger that activates the
    self-replication mechanism
  • Computer viruses versus Worms?
  • Anti-virus systems?

69
Part E Outline
  • Basics of Artificial Life ?
  • Finite State Automata Models
  • Evolutionary Computing

70
Artificial Life
  • Are systems which mimic natural life and are
    characterised as follows.
  • Have a finite lifetime from birth to death.
  • Use selective reproduction.
  • Their offspring inherit some of traits of the
    parents.
  • They use survival of the fittest (evolution).
  • They support the ability to expand in numbers to
    command a space or habitat.
  • They can respond to stimuli in a habitat, acting
    to maintain it and adapting to it.

71
Artificial Life
  • Living organisms are consummate problem solvers
  • Hence the motivation for use of artificial life
    models?
  • UbiCom Applications?

72
Finite State Automata (FSA) Models
  • There are different types of FSA
  • FSM can be represented in several ways,
    mathematically
  • FSMs can be used to model devices with a finite
    set of states such as off, on and standby.

73
Finite State Automata Models
74
(Multi) Cellular Automata Models
  • Are models of self-reproducing organisms
  • Can be designed in the form of a grid, where each
    cell is represented as an FSM
  • Cell exists in 1 of 2 states dead or alive
    which use basic transformation rules to transform
    a cell into dead or alive.
  • E.g., rules of Conways Game of Life

75
Conways game of life
This example illustrates the principle that
reactive type behaviours combined with a set of
simple transformation rules, when repeatedly
applied, can model more complex behaviours e.g.,
the gliding pattern
76
Multi) Cellular Automata Models
  • Other more complex rules of life can also be
    formulated.
  • Other examples of simple rules governing
    collective behaviour?
  • Rule model for flocks of animals (Section 10.4).
  • Multiple individual FSMs can also be
    interconnected to form device networks.

77
Evolutionary Computing
  • Evolutionary computing are computer algorithms
    which involve cumulative selections from a
    population of entities to solve a problem.
  • Behaviour of entities in the system is governed
    by implicit behaviours and goals,
  • Cumulative mean that in each generation or step
    of evolution, existing entities reproduce to form
    a new generation of entities.

78
Evolutionary Computing
  • Evolutionary computing originated from research
    in cell automata, the ideas also changed
    somewhat.
  • New generations are based upon the best traits of
    the previous generation rather than on rules
    which define how the existing generation
    transforms into the next one.
  • There is a set of possible outcomes for
    reproduction determined by natural selection.

79
Evolutionary Computing
  • Main types of evolutionary computing techniques
    include
  • Genetic Algorithms (GA) and Genetic Programming
    (GP),
  • Evolutionary Strategies (ES) and Evolutionary
    Programming (EP).

80
Digital Ecosystems
  • Digital ecosystem is analogous biological
    ecosystem which consists of a community
  • Set of organisms from different species
    interacting together
  • Organisms interact with and lives in harmony with
    their habitat.
  • Distributed Evolutionary Computing (DEC) as an
    extension of SOA
  • Evolutionary computing is used locally within an
    ecosystem to find individual members of ecosystem
    to satisfy locally relevant constraints.

81
Summary
82
Revision
  • For each chapter
  • See book web-site for chapter summaries,
    references, resources etc.
  • Identify new terms concepts
  • Apply new terms and concepts define, use in old
    and new situations problems
  • Debate problems, challenges and solutions
  • See Chapter exercises on web-site

83
Exercises Define New Concepts
  • Annotation

84
Exercise Applying New Concepts
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