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Mobile Agents for e-Mobile Agents for e-commerce commerce
Rahul JhaUnder the guidance of Prof. Sridhar Iyer
KR School of Information Technology , IIT Bombay
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
OverviewOverview
Mobile Agent applications in e-commerce Mobility Patterns and implementation
strategies Quantitative performance evaluation of
Voyager Evaluation of Voyager, Aglets and
Concordia Our Prototype of e-commerce application
using mobile agents
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
e-commerce applicationse-commerce applications Involve
– Product search– Order Placement and confirmations– Negotiations
Characterized by– Large amount of data exchange– Client specific services
Require– Real time interactions– Disconnected (or low bandwidth) shopping
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Mobile Agent advantages Mobile Agent advantages Mobile agents (MA)
– “A mobile agent is a program that can autonomously migrate between the various nodes of a network and perform computations on behalf of the user”
MA advantages– reduce network usage – faster response times– add client-specified functionality to servers– increase asynchrony between clients and servers– introduce concurrency
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Mobility patterns and Mobility patterns and Implementation strategiesImplementation strategies
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Implementation strategiesImplementation strategies
C
C
C
1
1 1
2
221
3 4 5 6
2
C
1 1
22
1
2
1
2 3
4
(a) Sequential Client Server (b) Sequential Mobile Agent
(c) Parallel Client Server (d) Parallel Mobile Agent
C Client
Server
Mobile Agent
Message exchange
Numbers along the arrows indicate the sequence of messages./ MA movement.
1 2 3 4 5 6
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Mobility Pattern Mobility Pattern ParametersParameters
DefinitionsItinerary the set of sites that an MA has
to visit staticdynamic
Order the order in which an MA visits sites in its itinerary.
static dynamic
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
SStatitaticc I Itinerarytinerary S Statictatic O Orderrder
H1 H2 H3
C
Itinerary
H4
H1 H2 H3 H4 H1 H2 H3 H4
Order
• Sequential CS • Sequential MA • Parallel CS • Parallel MA
Applicable Implementation Strategies
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
H1 H2 H3
C
Itinerary
H4
H1 H2 H3 H4 H1
Order?
SStatitaticc I Itinerarytinerary D Dynamic ynamic OOrderrder
• Sequential CS • Sequential MA • Parallel CS • Parallel MA
Applicable Implementation Strategies
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
H1 H2 H3
C
Itinerary
H4
H1 H1
Order? ?
• Sequential CS • Sequential MA • Parallel CS • Parallel MA
Applicable Implementation Strategies
DDynamic ynamic IItinerarytinerary
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Experimentation and Experimentation and resultsresults
The e-commerce application – A single client searching for
information about a particular product from the catalog of several on-line stores
– We assume that the client requires a highly customized search which the on-line store does not support.
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
ExperimentationExperimentation
Experimental setup– Voyager™ Framework for MA
implementations– Java™ socket based implementation
for client server interaction– On Pentium-III, 450 MHz workstations
connected through a 10 Mbps LAN with typical student load
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
ParametersParameters
assumed constant (all workstations on the same LAN)
network latencies on different links
10 ms to 1000 msprocessing time for servicing each request
~ catalog sizesize of client-server messages
20 KB to 1 MBsize of catalog
1 to 26number of stores
RangeParameters
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Performance metricPerformance metric User Turnaround TimeUser Turnaround Time
time elapsed between– a user initiating a request and
receiving the results. equals time taken for
agent creation +visit / collect catalogs + processing time to extract information.
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Effect of catalog size on Effect of catalog size on Turnaround Time Turnaround Time
0
2
4
6
8
10
12
14
0 2 4 6 8 10 12 14 16 18 20 22 24 26
No. of shops visited
Tu
rna
rou
nd
tim
e (
sec
)
MA
CS of catalog size 100K
CS of catalog size 200k
CS of catalog size 500K
CS of catalog size 1MB
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
processing = 20msprocessing = 20ms
0
2
4
6
8
10
12
14
16
0 2 4 6 8 10 12 14 16 18 20 22 24 26
No. of shops visited
Tu
rn a
rou
nd
tim
e (
se
c)
Sequential MA
Parallel MA
Sequential CS
Parallel CS
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
processing = 500msprocessing = 500ms
0
5
10
15
20
25
30
0 2 4 6 8 10 12 14 16 18 20 22 24 26
No. of shops visited
Tu
rnar
ou
nd
tim
e (s
ec)
Sequential MA
Parallel MA
Sequential CS
Parallel CS
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
processing = 1000msprocessing = 1000ms
0
5
10
15
20
25
30
35
40
45
0 2 4 6 8 10 12 14 16 18 20 22 24 26
No. of shops visited
Tu
rn a
rou
nd
tim
e (s
ec) Sequential MA
Parallell MA
Sequential CS
Parallel CS
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
ObservationsObservations Mobility patterns determine the
implementation strategies Sequential CS most suitable where
– a small amount of information has to be retrieved from few remote information sources.
Parallel implementations effective when – processing information contributes
significantly to the turnaround time.
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
ObservationsObservations
Mobile agents out perform traditional approaches when– When the cost of shipping MAs < message
exchange size. MAs scale effectively across the
parameters of E-commerce application
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Evaluation of Voyager, Evaluation of Voyager, Aglets and ConcordiaAglets and Concordia
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Features Voyager Aglets Concordia
Category
ORBMA based framework
MA based framework
Java messaging Transparent No No
Multicast Yes No No
Publish/Subscribe Yes No No
Scalability Space No No
Authentication and security
Strong implementation
Weak implementation
Strong implementation
Agent persistence Yes No Yes
Naming service Federated No No
Remote agent creation
Yes No No
Grouping / Collective
Logical Physical Physical
Garbage collection Yes No No
QQualitativeualitative C Comparisonomparison
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Mobility pattern : Product discovery
QQuantitative uantitative EEvaluationvaluation E Experimentsxperiments
assumed constant (all workstations on the same LAN)
network latencies on different links
20 msprocessing time for servicing each request
Kept constant for all 3 frameworks
Message packet size
1 MBsize of catalog
1 to 26number of stores
RangeParameters
Experimental setup : Same as that for previous experiments.
Performance metric : User turnaround time
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Cost of message exchangeCost of message exchange
Message exchange cost for different mobile agent frameworks
0
5
10
15
20
25
1 2 10 50 100 200 300 400 500
Numner of message packets
User
turm
aro
un
d t
ime i
n
sec
Concordia
Voyager
Aglets
Number
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Cost of code shipmentCost of code shipment
Code shipment cost for different mobile agent framework
0
500
1000
1500
2000
2500
0 2 4 6 8 10 12 14 16 18 20 22 24 26
No of shops
Tim
e in
ms
Concordia
Aglets
Voyager
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
ObservationsObservations
Voyager supports almost the super set of functionalities and features as compared to Aglets and Concordia.
Voyager being an ORB has advanced messaging support and hence performs much better than Aglets and Concordia.
Cost of code shipment for Voyager is more than Concordia (both user RMI)
– Voyager is an ORB with mobility support– Large set of functionalities supported by Voyager
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Our Prototype of e-Our Prototype of e-commerce application commerce application using mobile agentsusing mobile agents
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
Buyers GUI
List of shops to visit and dockyards
Product Request Template as
XML
Buyer's agent
Salesman agentSalesman agentSalesman agent
Product CatalogDBDB
Shops agent
Sales Transaction Log
Local services
ShopkeepersGUI
SHOP
Buyer
SHOP
SHOP
AArchitecture ofrchitecture of O Ourur P Prototype rototype
MModelodel
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
IInteraction nteraction among among
CComponentsomponents
Filtered Result
16th January 2001 M.Tech PresentationKReSIT, IIT Bombay
ConclusionConclusion
Helps user with tedious repetitive job and time consuming activities.
Faster and real time interacting at shops Reducing network load Support for disconnected operation. Introduce concurrency of operations Client specific functionalities at the shops