the world of autonomous reconfigurable systems intelligent interactive distributed systems group...
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The world of autonomous reconfigurable systems
Intelligent Interactive Distributed Systems Group Vrije Universiteit Amsterdam
http://www.iids.org/
Multi-level institutions of distributed autonomous systems
in regulated environments
Intelligent Interactive Distributed Systems Group Vrije Universiteit Amsterdam
http://www.iids.org/
•
autonomous adaptive/reconfigurable systems
Humans, p2p systems, agents, institutes,
embedded self-configuring systems,
autonomic computing systems,
All with some level of knowledge of
characteristics of their ‘owner’/organisation,their own tasks & reasoningother systems’ characteristics & roles
division of responsibility/liabilityof trust relationshipsof interaction design/negotiation
Requirements on the technology
Requirements with respect to users’ specific needs, including requirements wrt
• transparency • integrity• traceability• usability• …
Involving …
HCI autonomic computing design support systems trust models knowledge acquisition agent technology
model based diagnosis
distributed systems multi-modal interaction embedded systems machine learning cognitive engineeringuser centered design AI and design
Including interfacing with humans
How are autonomous systems perceived by users?
What types of interaction is needed at which levels and when?
Actor-agent community
Actor-Agent Community
agents actors
interfaces
middleware
Network and Computational Resources
Network and Computational Resources
Interaction required
for agents to acquire resources ……
SLAaWell-structured, protocol and language well-defined
Standard WSAS interaction
A
P
P
A
A P
Agreement request
agreement
templates
Extended WSAS interaction
• Two-tiered model (mediated) with
• Initial request phase
• Explicit accept phase
WSAS based mediated negotiation
A
M
M
A
A M
My requirements are …
This is the contract I’m offering you
A MAccept contract
A MWhat do you have to offer
P
P
P
P
P
P
These services are currently available
Mobach (2005)
WSAS based mediated negotiation
A M
A MInitial request
Offer template
P4
P1P3
P1
Initial request
P4
P1P3
P1Initial offers
WSAS based mediated negotiation
A M
A Mrequirements
contract offer
P4
P3
P1
request
P4
P3
P1offers
WSAS based mediated negotiation
A M accept contract
P3
P1
confirm
Very basic interaction
• Resource/service based
• Workflow – configuration of virtual organisation - responsibility of Mediator
• Implemented in the AgentScape agent platform
What if ……
Once everything’s in place, something goes wrong – a service fails.
• A new configuration of services/workflow is needed – in the above case the mediator needs to find a new configuration almost immediately
In other words: … ContextInitial situation: a web service configuration
Problem: one or more web services fail
Challenge: reconfigure, without exact match,using external web service
Approach: local knowledge in templates van Splunter, 2006
One option. Automated reconfiguration: running identical backups
Reconfiguration:Redirect all calls to identicalbackup service
If no exact match available FAIL
Another option: Semantic based approach: finding similar description
UDDI UDDI
Identify an (outside) web service that offers equal functionality
Transform calls to syntax ofoutside service and redirect calls
UDDI
Still need exact match?
In all cases: a need to prepare for reconfiguration – eg using templates
Structure the web service configuration in templates, to enable reconfiguration
Template-based Reconfiguration
• Structure the dependencies between services
• Creating compositional abstract web services
• Integrate local knowledge
Reconfiguration using templates
Reconfiguration using templates
UDDIReconfiguration Service
insertion
manage data
data extraction
manage
handle storage
data
template
store data slot
Reconfiguration using templates
insertion
manage data
data extraction
manage
handle storage
data
template
Concise description of a template
Simple example of local knowledge
Exec_timetemplate= Exec_timeretrieve + Exec_timestore + Exec_timefilter + Exec_timecreate
Simple example of local knowledge – QoS parameters
Exec_timetemplate
= Exec_timeretrieve + Exec_timestore + Exec_timefilter +Exec_timecreate
insertion
manage data
data extraction
manage
handle storage
data
template
Local knowledge
Local knowledge: define a function in a template for a specific property based on the properties of the templates direct constituents
Exec_timetemplate= Exec_timeretrieve +
Exec_timestore + Exec_timefilter +
Exec_timecreate
What if ….
More than one level within an organisation is involved: multiple compositions of workflows (institutions/configurations of services)
needed
Multi level organisations/institutions
• Strategic level (gold)• Tactical level (silver)• Operational level (bronze)• Network level
Each with own criteria
• Goals• Evaluation criteria (KPI)• Workflows• Concepts• Own “local” knowledge
Interaction between levels is needed
but …… to which extent do levels need to share/communicate:• Goals• Expectations• Context• Trust• Organisation• Ontologies• Processes, …..
As each level reasons …
• with the information they acquire from both higher and lower levels
• about when to request/provide information to other levels and/or other (possibly human) systems at the same level
Regulated environments – what’s needed?To understand the relationship between the levels: is it
compositional?
To agree on standards for protocols, contracts for interaction with system support (middleware).
To understand the role of the users/owners organisations in such distributed environments.
To explore legal implications of different technologies.(eg multi-media retrieval)
To develop supporting technology
How?
• Explore multiple scenarios ……
(eg financial transaction systems, crisis management, business workflow support, …..)
Explore different use cases ….
Also requires technology …
Frameworks for • scalable, • interactive, • secure, • robust, • interoperable• distributed autonomous systems/agents• supporting service agreement negotiation• and service agreement enforcement
An example: Agentscape Framework
designed to support large scale distributed mobile agent applications.
• a distributed agent operating system kernel (AOS)
• services • agent management• lease management (ie resource mgt based
on WSAS)• directory services• web service access gateway• configuration services
AgentScape
Platform for mobile agents
Agent Operating System
agentserver
WS gateway
locationmanager
ws
AgentScapeInterface
AOS Interface
XML-RPC
SunRPC
hostmanager
agent
