A Combinatorial Procurement Auction

bevyquixoticSecurity

Nov 3, 2013 (4 years and 10 days ago)

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E
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Commerce Lab
, CSA, IISc

1

A Combinatorial Procurement Auction
for QOS
-
Aware Web Services
Composition

Megha Mohabey, Y. Narahari

Computer Science and Automation,

Indian Institute of Science, Bangalore


Sudeep Mallik, P. Suresh, S.V. Subrahmanya

Infosys Technologies

Bangalore


September 2007

E
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Commerce Lab
, CSA, IISc

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Overview



Web Services Composition Problem



Motivation, Research Gap and Contributions



QWESC: A Tool for QOS
-
Aware Web Service Composition



Combinatorial Auction for Web Services Composition



Conclusions and Future Work

E
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Commerce Lab
, CSA, IISc

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Web Services


Network
-
resident software services accessible via
standardized protocols



Can be automatically exposed, discovered, and invoked
by other applications



Business processes and application functionality are
becoming available as web services .



Can be endogenous or exogenous



Available often as commercial web services from
enterprise solution vendors and web services
marketplaces.


Eg.

www.strikeiron.com
,
www.amazon.com
,
www.google.com


E
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Commerce Lab
, CSA, IISc

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Web Services Composition Problem


Types of web services:


Stand
-
alone Web Services
-

Represent a single activity in a
business process


Composite Web Services
-

Represent more complex business
logic often encompassing multiple business steps



Web Service Providers (WSPs) may offer web services
with different Quality of Service (QoS) and service level
agreement (SLA) guarantees.



Dynamic creation of business processes requires
composing an appropriate set of web services that best
suit the current need.

E
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Commerce Lab
, CSA, IISc

5

Problem Definition


To find the best mix of web services that achieves well
defined cost and quality criteria for the execution of an
end
-
to
-
end composite service as desired by a WSR




We propose an approach to get the optimal execution
plan for a single execution path.

A

B

C

A Simple Statechart

E
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Commerce Lab
, CSA, IISc

6

Related Work


L. Zeng, B. Benatallah, A. H. Ngu, M. Dumas, J. Kalagnanam, and H. Chang, “Qos
-
aware middleware for web services composition,” IEEE Trans. Softw. Eng., vol. 30,
no. 5, pp. 311

327, 2004.


QoS modeling and QoS aware web services composition



Y. Gao, B. Zhang, J. Na, L. Yang, Y. Dai, and Q. Gong, “Optimal selection of web
services for composition based on interface
-
matching and weighted multistage
graph,” in PDCAT ’05: Proceedings of the Sixth International Conference on Parallel
and Distributed Computing Applications and Technologies. Washington, DC, USA:
IEEE Computer Society, 2005, pp. 336

338.


Interface matching



G. Canfora, M. D. Penta, R. Esposito, and M. L. Villani, “An approach for qos
-
aware
service composition based on genetic algorithms,” in GECCO ’05: Proceedings of the
2005 conference on Genetic and evolutionary computation. New York, NY, USA:
ACM Press, 2005, pp. 1069

1075.


Genetic algorithm based approach

E
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Commerce Lab
, CSA, IISc

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Research Gap and Contributions



Current approaches consider the problem of composition
of stand
-
alone web services to form an end
-
to
-
end
composite service.



We present a novel combinatorial auction approach to
dynamic web services composition that considers both
stand
-
alone and composite services for forming an end
-
to
-
end composite service.



We design a software tool, QWESC (QoS
-
Aware WEb
Services Composer), for web services composition
based on the proposed approach.


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Commerce Lab
, CSA, IISc

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Motivating Scenarios for Combinatorial
Auction Approach




A WSP may be willing to provide a composite service at a price
lower than the total price of stand
-
alone services that form the
composite service.


The quality attributes of a composite service offered by a WSP
may not be the same as achieved by composing its constituent
stand
-
alone services.


Different WSPs may have different number of stages/steps for
achieving the same task and they can expose the services at
different points.

E
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Commerce Lab
, CSA, IISc

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QoS Monitoring

Abstract Process Designer

QoS Registry

QoS Ranking

Enhanced UDDI

Discovery Engine

Preprocessor

Optimization

Problem

Formulator

IP Solver

Optimal

Solution

Web Service

Binder and

Execution Engine

WSP 1

WSP n

Web Service

Web Service

QWESC

(
Q
oS
-
Aware
WE
b
S
ervices
C
omposer)

Publish
(WSDL)

Web Service
Requestor

Service
Template

Service
Description

Message Exchange
(SOAP)

QoS
Feedback

Payment

Determination

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Commerce Lab
, CSA, IISc

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Combinatorial Auction Approach


A web service requestor (WSR) wishes to buy a set of distinct web
services A .



There is a set of web service providers (WSPs) who are interested
in selling the entire set or some subsets of A.



The WSPs submit combinatorial bids



If a WSP can provide services A, B, C, AB, and BC, and there are
two quality attributes, then the bid will look as follows:




< ({A}, q1, q2, c(A)), ({B}, q1, q2, c(B)), ({C}, q1, q2, c(C)),


({A,B}, q1, q2, c(AB)), ({B,C}, q1, q2, c(BC)) >


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Commerce Lab
, CSA, IISc

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Notation

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Commerce Lab
, CSA, IISc

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IP Formulation

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Commerce Lab
, CSA, IISc

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Experimental Results

Announcements by WSPs

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Commerce Lab
, CSA, IISc

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Experimental Results (contd…)

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Commerce Lab
, CSA, IISc

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Experimental Results (contd…)

THE VALUE OF VARIOUS ATTRIBUTES

(C
-

WITH COMBINATORIAL BIDS,

NC
-

WITHOUT COMBINATORIAL BIDS)

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Commerce Lab
, CSA, IISc

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Future Work


Generalized Model


Current work limits discussion to that of a linear execution path.


Introducing forks and joins will model a more generalized scenario.



Interface Matching and SLA handling


The services offered by different WSPs may not be interoperable, if they
have incompatible input output interfaces.


WSPs may provide service at various levels of quality guarantee
violation of which may attract some form of penalty.



Game Theoretic Approach


A rational WSP may not find it in its best response to reveal true
information about the web services provided by it.


To ensure truth revelation by WSPs, an appropriate incentive scheme
has to be designed.

E
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Commerce Lab
, CSA, IISc

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Questions and Answers




Thank You