Research Article
A Service Chain Discovery and Recommendation Scheme Using
Complex Network Theory
Guoqi Liu, Yuli Zhao, Zhuang Wang, and Ying Liu
College of Soware, Northeastern University, Shenyang 110819, China
Correspondence should be addressed to Ying Liu; liuy@swc.neu.edu.cn
Received October ; Revised December ; Accepted December ; Published January
Academic Editor: Yuncai Wang
Copyright © Guoqi Liu et al. is is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Service chain discovery and recommendation are signicant in services composition. A complex network module based algorithm
using services invocable relations is proposed to search useful service chains on the network. Furthermore, a new scheme for
discovering composite services processes automatically and recommending service chains by ranking their QoS is provided.
Simulations are carried out and the results indicate that some useful service chains in the dataset provided by the WSC can be
found by the new algorithm.
1. Introduction
Web service was widely applied for its outstanding advantages
like self-describing, self-containing, and easy deployment. In
order to implement complex business ow, composition of
existing web services is a common way to solve the problem
[]. Web services composition includes a serious of services
by service relations and generates a behavior chain to meet
user requirements, which is called a web service chain []. A
service chain should not only satisfy the functional require-
ments of users but also make sure that all of the services
in the chain are correct and reliable. Consequently, how to
compose web services to discover service chains according to
service relations is very crucial.
In web service, the compatibility and integral eciency of
composed services should be considered during the compo-
sition procedure of web services. Web services are combined
according to the attributes and functions of both services
provided and the user requirements [, ], especially a lot of
works have been proposed in this eld of quality-driven web
services composition [–].
Recently, some researchers have proposed a lot of algo-
rithms using graph theory to discover service composition
[], in which the services and the relations among them
are treated as nodes and edges, respectively. In this kind
of methods, the composition of web services is achieved
by looking for feasible path among the nodes. e aw of
these schemes is that the research on graph theory tends to
be theatrical research rather than the actual situation. As a
matter of fact, the web services are distributed on the web
servers on the Internet, and the basic structure and charac-
teristics of it are more like a complex network. erefore,
the basic architecture model of web services is complex net-
work rather than a graph. In this paper, we rstly analyze the
scale-free and small-world features of the complex network
we created, which illustrates the basic structure is a complex
network. e traditional graph theory cannot reect the
actual distributed structure of web services.
e compatibility problem of web services can be solved
by using a specic complex network model, which is created
by matching the input and output interface of each service.
However, there are still two problems, the structure and
integral quality problems among services. In Section ,a
method for identifying the structure of web services in com-
plex network is proposed, and a recommendation algorithm
of high quality service chain is proposed. erefore, the rec-
ommendationschemeofservicechainincomplexnetwork
is shown.
In this paper, a new service chain recommendation
scheme based on complex network is proposed, in which
webservicesandtherelationsamongthemaretreatedas
the nodes and edges of the network, and both of them
Hindawi Publishing Corporation
Mathematical Problems in Engineering
Volume 2014, Article ID 157085, 6 pages
http://dx.doi.org/10.1155/2014/157085