From: Proceedings of the Second International Conference on Multiagent Systems. Copyright © 1996, AAAI (www.aaai.org). All rights reserved.
for
An Agent-based
Flexible
Multimedia
Architecture
Communication
Networks
Takuo Suganuma*, Shigeru Fujita t, t,
Kenji Sugawara
Tetsuo Kinoshita t t and Norio Shiratorit t
Dept. of ComputerScience, Chiba Institute of Technology
2-17-1, Tsudanuma, Narashino, Chiba 275, JAPAN
" Research Institute of Electrical Communication,TohokuUniversity
.....
2-1-1, Katahira, Aoba-ku, Sendai 980, JAPAN
{suganuma,
fujita,
sugawara}@suga.cs.it-chiba.acjp
{kino,
norio}@shiratori.riec.tohoku.ac.jp
To performthe multimediacommunication
across
theinternet,
thefollowing
operations
or
adjustments
areresponsible
fortheusers:
(a)the
decision
ofthemostsuitable
setting
of thesystem
configuration
anditsparameters
to realize
the
QoSwhichtheirownrequirements
arereflected
by,(b)theselection
of themostappropriate
working parameters considering the
system/network
performances
in run-time.
But
the essential
multimedia
properties
makethe
non-expert
usersimpossible
to operatethe
application
at ease.Theflexible
network
we have
proposed
[Shiratori
et al. 1994)monitors
the
current users’ requirementsand system
performances,
and controlsthe application
configuration
and parametersproperlyto
maintain
the users’satisfiabilities
andthe
systems’
stabilities.
Theflexibility
is realized
usingtheMAS,in whichvarious
typesof agents
thatembedthe domainknowledge
of thedesign
and operational
expertsof the multimedia
applications. The ADIPS (Agent-based
Distributed
Processing
System)framework
is
utilized
as MASframework
to achieve
ourgoal.
ADIPSframework: ADIPSis an agent-oriented
distributed processing system designed by the
agentification of various computational processes
that provide the services of the traditional
distributed
system (Kinoshita,
Sugawara
Shiratori 1995). The agentification
is the
methodology to construct the active process
component by embedding the knowledge of
designers/operators of the distributed systems
intothetraditional
computational
process.
Agentarchitecture:
An agentin ADIPSconsists
of Cooperation Mechanism (CM), Domain
Knowledge(DK) and ProcessingMechanism
(PM).
Agenttype:Two typesof agentsin ADIPScan
be distinguished
in termsof theirmodularity,
the ADIPSagentand the Component
agent.The
former
represents
thedistributed
application
and
thelatterrepresents
a component
of theADIPS
agent.
ADIPS Agent Repository
and Workspace:
There are two types of the agent working
environment, i.e., Agent Repository(AR) and
Agent Workspace(AWS). The agents in the
are called the Class agents which have the domain
knowledgeon howthey configure the application.
The configuration is performed based on the
ability knowledgeon the system componentwhich
the agent is responsible for using the contract-net
protocol. The agents in the AWSare called the
Instance agents which are instantiated from the
ARand control actual processes in run-time.
Weare implementing the ADIPS-basedflexible
video conferencing
system. The system’s
flexibility are illustrated as follows:(1)The Class
agents in the ARnegotiate based on the users’
requirements against the video conferencing and
the static/dynamic properties of the system and
network. The most appropriate configuration is
built onto the AWSautonomously and the video
conference session starts in the required QoS,
(2)The ADIPSagents for the video conferencing,
ADIPS-VideoConference agents, negotiate to
adapt to the changes of the users’ requirements
and system performance.
The negotiation
outcomes specify the working parameters of the
processes,
(3)In the case that the agent
organization can not provide the sufficient QoS,
the re-configuration request is issued to the AR
and the refined organization are loaded onto the
AWS.
Currently, we are working on the experimental
study
to evaluate
theflexibility
ofthesystem.
References
Shiratori, N., Sugawara,K., Kinoshita, T. and
Chakraborty, G. 1994. Flexible Networks: Basic
Concepts and Architecture. IEICE Trans.
Commun.,Vol.E77-B, No.11, pp.1287-1294.
Kinoshita, T., Sugawara, K. and Shiratori, N.
1995. Agent-based Frameworkfor Developing
Distributed Systems. Proceedings of CIKM’95
Workshopon Intelligent Information Agents.
Suganuma 459