Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 1
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Lecture 1: Introduction to Self-
Organization
Self-Organizing
Dr.-Ing. Abdalkarim Awad
13.10.2011
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 2
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Introduction to Self-Organization
• Why is it important?
=> Motivation for Self-organization
• What does it mean?
=> Definition of Self-organization
• How does it work in practice?
=> Examples for Self-organization in Communication
Systems
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 3
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Why a course on self-organizing systems?
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 4
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Motivation- Internet
• Traditional
– Client-Server
• Current and future
– Internet of things
– Virtualization (i.e. Peer-to-Peer (P2P) and overlay)
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 5
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Motivation- Internet
• Example: data storage/retrieve problem!
Where to store and how to find certain data element (file)?
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 6
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Client/Server (Server Stores the Data)
• Well known approach
• Server is a data
source
• Clients request
data from server
• Sever is a powerful
computer
• Clients have usually
lower capabilities
I need data “titanic.avi”
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 7
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Unstructured P2P (Server knows info.)
I have data “titanic.avi”
I need data “titanic.avi”
• A way to share files with
others
• Users upload their list of files
to server
• You send queries to for files
of interest (e.g. Song)
• server replies with IP address
of users with matching files
• You connect directly to user A
to download file
• Example Napster , Skype
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 8
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Structured P2P (DHT)
Distributed Hash Table -DHT
I have data “titanic.avi” Hash(“titanic.avi”)=7 Put(7,titanic.avi)
I need data “titanic.avi” Hash(“titanic.avi”)=7 Get(7)
1
3 5
8
11 12
0
5 .
8 .
0 .
1 .
3 .
5 .
8 .
11 .
• Decentralized
• Autonomous
components
• Mapping
E.g. Map
Filename to
Node ID
• Nodes have partial
view about the
network
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 9
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Motivation- Internet
• Think about! (Which system can be self-organizing?)
– Which system has a central entity?
– Where do we have single node of failure?
– What about the capabilities of the computers (server)?
– …
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 10
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Comparison
Client Server Unstructured´P2P Structured P2P
Scalability Bad Middle Good
Cost Bad Middle Good
Reliability Good Bad Bad
Single node of failure
Bad Middle Good
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 11
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Motivation- Next Generation Mobile
Communication Systems
• Mobile communication systems in the past
– Manual configuration
– Manual adaptation (optimization)
– Manual repair
– Central controller (e.g. RNC)
• Mobile communication systems in future
– Large, complex and dynamic
– No central controller (several functions are moved to BS)
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 12
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Motivation- Next Generation Mobile
Communication Systems femtocell networks
• Massive deployment of user-operated home-base stations (femto-access points) for cellular communications demands for decentralized radio resource allocation
• Lacking any central authority having complete control of the network topology, the system must incorporate self-organization, self-healing capabilities
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 13
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Transition to LTE/SAE: Architecture
GPRS Core
(Packet Switched)
SGSN
GGSN
Internet
GSM
RAN
Base station
Base station controller
Base station
Base station
UTRAN
Radio network controller
node B node B
node B
MSC
PSTN
GSM Core
(Circuit
switched)
HLR AuC
EIR
GMSC
E- e-
e- e- S-GW
P-GW
IMS
EPC
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 14
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Motivation- Ad hoc Networks
• Example: Wireless Sensor Networks – Massive deployment of sensors in difficult to reach areas
(e.g. deployment by aircraft)
– Self-organization capabilities in terms of sensing and inter-node communications
– All nodes initially have the same configuration (No IP or
MAC address)
– Robustness to node failure and self-healing mechanisms are important
– Limited resources
– Energy efficient
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 15
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
15
Problem of today´s networks – Heterogeneity
– Dynamics
– Scalability
Method: Self-organization – Fast, autonoms reaction to problems
– Automation of control
– Distributed control
Some application scenarios: – Severe network impact due to disasters
– Energy savings
– Privately operated femto cells
Motivation for Self-Organization
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 16
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Self-organized Service Recovery S Reconfigurable Radio
Interfaces R
Cognitive Management of Transport Resources T
Our Application Interest in Self-Organization
Decentralized Information Management I
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 17
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
17
Research Topics – Secure Network Operation How can access to adhoc-deployed communication infrastructure be restricted?
– Innovative authentication techniques based on localization?
– How to ensure secure localization?
– How to configure/manage access rights, cryptographic keys etc.?
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 18
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
18
Research Topics – Integration of UAVs
image source: http://gallery.mikrokopter.de
Self-organized integration of mobile platforms (land-based and airborne)
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 19
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Self-org is a vital need for complex systems
• The term complex system formally refers to a system of many
parts which are coupled in a nonlinear fashion. A linear
system is subject to the principle of superposition, and hence
is literally the sum of its parts, while a nonlinear system is not.
• When there are many nonlinearities in a system (many
components), its behavior can be as unpredictable as it is
interesting.
• Local rules, which describe the
behavior of each entity in the
system, lead to complex
global states.
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 20
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Are Self-Organizing Techniques Unique Solutions?
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 21
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Are Self-Organizing Techniques Unique Solutions? NOT Necessary
What are they good for?
Remember Client-Server and P2P!
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 22
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Drivers for Self Organizing Networks
• Technological drivers
– The complexity of systems
• Market drivers
– Reduce Capital EXpenditures (CAPEX)
• For example applying self-configuration algorithms reduces
human effort in the installation
– Reduce Operational EXpenditure (OPEX)
• For example applying self-optimization algorithms reduces
the power consumption
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 23
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Natural Systems
• Non-living systems
– Sand dune ripples
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 24
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Natural Systems
• Living systems
– Zebra stripes
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 25
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Natural Systems
• Living systems (social)
• Ants
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 26
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Natural Systems
• Living systems (social)
• School of fish
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 27
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Self-Organization and Emergence
• Emergent phenomena – pattern / function / property /structure
• Examples: – Sand dune ripples
– Zebra stripes
– Emergence of consciousness in human • Emerges from neurons interactions
– Shortest path to food found by foraging ants
– Engineered systems: • TSP: shortest path to visit all cities
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 28
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Self-Organization and Emergence
• A self-organizing system produces complex organization
from randomness based on local interaction and without
external intervention
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 29
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Self-Organization and Emergence
• Emergent Phenomena do not appear on the individual
component level but on the global level
• Emergent Phenomena is far beyond the capabilities of
individual components
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 30
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Self-Organization-definition
• Self-organization in Engineered systems “Self-organization is the process enabling a system to change its organization in case of environmental changes without explicit external command .”
• “Strong self-organizing systems are those systems where there is reorganization with no explicit central control, either internal or external.”
• “Weak self-organizing systems are those systems where, from an internal point of view, there is re organization under an internal central control or planning.”
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 31
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Properties of self-organizing systems
• No central entity
• No external controller
• Global behavior results from local interaction
• No global pattern / recipe / rule to refer to
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 32
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Capabilities of Self-Organizing systems
• Self-configuring
– The process where newly deployed components are configured
by automatic installation procedures to get the necessary basic
configuration for system operation
• Self-optimization
– Ability of the system to optimize the local operation parameters
according to global objectives
• Self-healing
– Methods for changing configurations and operational parameters
of the overall system to compensate failures
• Self-protection
– System automatically defends against malicious attacks or
cascading failures. It uses early warning to anticipate and
prevent system wide failures [Kephart 03]”
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 33
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Limitations of self-organizing approaches
• Controllability
• Cross-mechanism interference
• Difficult assessment of the
mechanisms
– Large scale
– Dynamic
– Complex
– Unpredictable environment
• New software engineering
approaches are needed
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 34
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Natural Self-Organization and “Bio-Inspired”
• Echolocation mechanisms in many animals have always
been a source of inspiration for radar waveform design
• The chirp acoustic signals emitted by bats/dolphins are
very similar to the radar waveform
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 35
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Natural Self-Organization and “Bio-Inspired”
Principles of echolocation (bio-sonar)
The 18th century Italian scientist Lazzaro Spallanzani had, by means of a series of elaborate experiments, concluded that bats navigate by hearing and not by vision
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 36
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Bio-Inspired
• Routing based on Ants behavior
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 37
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Design Steps of Bio-inspired Solutions
• Analogy
– Study the analogy between the biological system and our
system (ICT problem)
• Modeling and simulation
– Obtain a realistic model
• Testing
– Explore the performance
• Implementation
– Implement the system
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 38
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Engineering of Self-Organizing systems
• Positive and Negative Feedback
• Direct and indirect interaction
• Decentralized Control
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 39
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Positive Feedback
• Initial change in a system is reinforced in the same
direction as initial change
– Towards amplification
– Implies changes in the system
• Ex: Fish nesting
– Initial change = some fishes nest close to each other
– Positive feedback rule = “I nest where other similar
individuals nest”
– Increased aggregation of fishes at the same place
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 40
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Negative Feedback
• Perturbation applied to system triggers response that counteracts the perturbation
– Towards stabilisation
– Avoids fluctuations
• Ex: maintain a constant distance to your neighbors
– Negative feedback = A bird is close to flock (swarm)
– Response = Decrease speed
– Result = Avoid collisions with neighbors
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 41
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Positive Feedback coupled with Negative Feedback
• Positive feedback pushes system towards its limits
• Negative feedback or physical constrains provide inhibition and maintain system under control
• Ex: Fish nesting – Rule = “I nest where other similar individuals nest unless
there are too much fishes”
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 42
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Direct Communication
• Schools of fishes – Information acquired from neighbour
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 43
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Indirect Communication
• Information acquired from shared local environment and work-in-progress : Stigmergy
• Social Insects
– Ants deposit pheromone along traveled path which is
used by other ants to follow the trail.
– This kind of indirect communication via the local
environment is called stigmergy
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 44
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Decentralized Control
• Coordination of work without central decisions
• Self-organization mechanisms are (mostly) based on
decentralized architectures of information flow
– No instruction issued from leaders
– Individuals gather information (directly or not) and decides
what to do
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 45
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Decentralized Control
• Two kinds of engineered systems with decentralized
control
– Case 1: Large set of autonomous components, pertaining
to the same system and providing as a whole expected
properties, or functions.
• Engineering with emergent functionality in mind
– Case 2: Large set of autonomous components,
spontaneously interacting with each other, for possibly
independent or competing reasons.
• No expected emergent global function or properties
• In both cases, autonomous components may be
• Heterogeneous
• dynamically joining and leaving the system.
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 46
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Dynamic Change
• Continual interactions among components
• Components join and leave system at any time
• Dynamic systems
– Ants foraging
– Skype system of users
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 47
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Research Directions
• Self-Organizing methods to solve problems in next
generation networks
• Evaluation of self-organizing methods
• Not discovered bio-Inspired approaches
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 48
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
Summary (what do I need to know)
• Why self-organizing systems?
• What is emergence phenomena?
• What are the characteristics of self-org systems?
• What are the advantages and disadvantages?
• What do we mean by bio-inspired approaches?
• What is Positive and Negative Feedback?
• What is direct and indirect communication?
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 49
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
References
• Slides “Evaluation of self-organizing systems using
quantitative measures ” by Hermann de Meer, Richard Holzer,
Patrick Wüchner
• Slides “Adaptive Systems” by Giovanna Di Marzo Serugendo
• Slides“ Bio-Inspired Signal Processing” by Sergio Barbarossa
• Slides “Self-Organization in Sensor and Actor Networks” by
Falko Dressler
• F. Dressler, Self-Organization in Sensor and Actor Networks.
John Wiley & Sons, December 2007
• E. Bonabeau, M. Dorigo, and G. Théraulaz. Swarm
Intelligence: From Natural to Artificial Systems Santa Fe
Institute Studies on the Sciences of Complexity. Oxford
University Press, UK, 1999.
Introduction to self-organization
Dr.-Ing. Abdalkarim Awad
Page 50
Prof. Dr.-Ing. habil. Andreas Mitschele-Thiel
Integrated Communication Systems Group
www.tu-ilmenau.de/ics
References
• E. Bonabeau, M. Dorigo, and G. Théraulaz. Swarm Intelligence: From Natural to Artificial Systems Santa Fe Institute Studies on the Sciences of Complexity. Oxford University Press, UK, 1999.
• S. Camazine, J.-L. Deneubourg, Nigel R. F., J. Sneyd, G. Téraulaz, and E.Bonabeau. Self-Organisation in Biological Systems. Princeton Studies in Complexity. Princeton University Press, 2001.
• J.H. Holland, Emergence – from Chaos to Order. Oxford University Press, 1998
• M. Wooldridge: An Introduction to Multi-Agent Systems. Wiley, 2003
• L. M. de Castro: Fundamentals of Natural Computing – Basic Concepts, Algorithms, and Applications. Chapman & Hall/CRC. 2006.