Automated Management of Ubiquitous
Systems for e-Science
Prof. J. Sventek
University of Glasgow
joe@dcs.gla.ac.uk
In collaboration with M. Sloman, E. Lupu, and N.
Dulay of Imperial College London
http://www.dcs.gla.ac.uk/amuse
Overview
• Management in pervasive systems cannot rely on human
intervention or centralized decision making functions.
• It must be devolved, based on local decision making and local
feed-back control loops embedded in autonomous components.
• We have proposed the concept of a self-managed cell (SMC) as
an architectural pattern for building ubiquitous computing
applications, where an SMC consists of hardware and software
components that form an autonomous administrative domain.
• SMCs may be realized at different scales, from body-area
networks for health monitoring, to an entire room, to a widearea network.
• To scale to larger systems, it is necessary for SMCs to
collaborate with each other, to federate and compose into
larger SMC structures.
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e-Science AHM Presentation
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The Feedback Control Loop
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Self-Managed Cell
Architecture
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Architectural Choices
• Event bus is publish/subscribe using a router
• The router is content-based
• A discovery/membership service is concerned
with keeping track of which devices and
services are “in” a self-managed cell
• Each device has a unique identifier (e.g. 802.*
MAC address of one of the communication
interfaces)
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At-most-once, persistent
event delivery
purge ‘subscriber’
Publisher
filter
Router
Subscriber
S
P
•
•
•
•
•
•
S
S
No session establishment for Publisher
Subscriber must register ‘filter’ and callback
Push of event from Publisher to Router (and Router to Subscriber)
is synchronous – i.e. exception condition is returned to sender if
unsuccessful
Router attempts to deliver a message until it knows that a
Subscriber is no longer a member of the SMC
When purge event received, removes ‘filter’ and any queued
messages associated with that Subscriber
Each Subscriber is guaranteed to receive all messages from a
particular publisher in the same order as received by the Router
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e-Science AHM Presentation
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How to incorporate a mote
into this structure?
Mote
Proxy
S
S
Proxy
Mote
S
S
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Discovery/Membership
• Detect new devices within communication range
• Vette device for membership
– obtain device profile
– perform any required authentication
• Generate new cell member event
• Determine when device leaves cell
– Generate cell member left event
• Discovery protocol does NOT use the event system to
discover and negotiate with devices; the discovery
service does use the event service to announce
member added/removed
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e-Science AHM Presentation
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Communication primitives
required
• Event bus is only used for communications
between cell management elements
• Basic communication primitives are required
to implement the event bus communications,
required protocols, and general communication
between application components
–
–
–
–
broadcast, asynchronous messaging
multicast, asynchronous messaging
unicast, asynchronous messaging
remote method invocation
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SMC on a gumstix
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Federated SMCs
• Peer SMCs (peer devices, peer networks, SLAs…)
Measurement
& Monitoring
Interaction
Adaptation
Measurement
& Monitoring
Service
Discovery
Raw
Measurements
Goals and
policies
Service
Discovery
Raw
Measurements
Event Bus
Policy
Management
Interaction
Adaptation
Measurement
and Control
Adapters
Context
Context
Information
Managed Resources
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…
Event Bus
Other
Policy
Management
Goals and
policies
Measurement
and Control
Adapters
Context
Other
Context
Information
Managed Resources
e-Science AHM Presentation
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SMC Composition
Measurement
& Monitoring
The enclosing
SMC “programs”
the nested
SMCs
Event Bus
Policy
Management
Measurement &
Monitoring
Service
Discovery
Measurement and
Control Adapters
Interaction
Adaptation
Interaction
Adaptation
Policy
Management
Measurement and
Control Adapters
Other
Context
Service
Discovery
Measurement &
Monitoring
Event Bus
Event Bus
Context
Policy
Management
Managed Resources
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Service
Discovery
Interaction
Adaptation
e-Science AHM Presentation
Measurement and
Control Adapters
Context
Managed Resources
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Federation Essentials
• Architecture – traditional flat, one-dimensional
architecture vs. hierarchical, multi-tiered architecture
• Ontology – federates must possess an agreed vocabulary
of common terms and their meanings
• Security and privacy – as the level of integration increases
between autonomous managed resources, protecting the
security and privacy of these resources also increases; it
is critical not to assume that every federate has access to
all distributed resources; there may be a natural
precedence among federates
• Negotiation – given the potentially ephemeral nature of
these federations, negotiation protocols between SMC’s to
create these federations are essential
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Interaction Establishment
Overview
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Missions Across SMCs
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Conclusions
• Prototype implementation has demonstrated that the
SMC pattern can be applied to e-Health applications
• Event bus provides sufficient performance,
modularity, and scale to adequately address e-Health
management traffic
• ECA policy-based management provides a simple and
effective strategy for encoding the necessary
adaptation strategy for e-Health applications
• Effective peer-to-peer federation approach has been
designed, implemented, and tested
• Wide area implementation of SMC is in progress.
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Publications
•
•
•
•
•
•
“Supporting Interactions between Self-Managed Cells”, Proceedings of
the IEEE International Conference on Self-Adaptive and SelfOrganizing Systems, Boston, Massachusetts, USA, July 2007
“Policy-based Management of Body-Sensor Networks”, Proceedings of
the International Workshop on Wearable and Implantable Body Sensor
Networks, Aachen, Germany, March 2007
“An Event Service Supporting Autonomic Management of Ubiquitous
Systems for e-Health”, Proceedings of International Workshop on
Distributed Event-Based Sytems, Lisbon, Portugal, July 2006
“Self-Managed Cells for Ubiquitous Systems”, Proceedings of the 3rd
Intl Conference on Mathematical Methods, Models and Architectures
for Computer Networks Security (MMM-ACNS 2005), St Petersburg,
Russia, LNCS 3685, pp. 1–6, Sept 2005
“AMUSE: Autonomic Management of Ubiquitous e-Health Systems”,
Proceedings of the UK e-Science All Hands Meeting, Nottingham, UK,
September 2005
“Self-Managed Cells and their Federation”, Workshop Proceedings of
the 17th Conference on Advanced Information Systems Engineering
(CAiSE’05), June 2005
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