An Effortless Approach for Migrating from Legacy Software Systems to Web Services

1.Introduction

In today’s computing era, interoperability is one of the key non-functional requirements of software systems. This is particularly due to tremendous and endless growth of internet and its infrastructure. Mostly legacy software systems do not inherently have this interoperability feature as part of its structure. Thus one of the reasons for reverse engineering legacy software systems is to make it interoperable. Another vital reason is that to incorporate new features possible through recent advancements in technologies and exploit their advantages for users’ satisfaction to the fullest extent feasible in the system. In either case as for as legacy software systems are concerned reverse engineering is the first step to be executed. Software reverse engineering is the process of analyzing a subject system to: identify the system’s components and their interrelationships: create representations of the system at a higher level of abstraction (Chikofsky, 1990). In today’s computing arena, web services are emerging as solution for software systems due to ubiquitous availability of internet. Web services are emerging as a promising technology for the development and deployment of E-applications and for the effective automation of inter-organizational interactions (Djamel et al., 2008). The W3C web services architecture working group defines a web service as: “A software application identified by an URI, whose interfaces and bindings are capable of being defined, described and discovered as XML artifact. A web service supports direct interactions with other software agents using XML-based messages exchanged via internet-based protocols” (Web Services architecture, 2002). By overcoming interoperability limitations, web services allow the integration of existing software systems by exploiting the pervasive infrastructure of the world wide web and offer a renewed opportunity to continue using/ reusing the business functions provided by legacy systems (Canfora et al., 2006).

Software metrics is emerging as better information support for software project management and producing software effectively and efficiently at cost-effective manner. A software metric is quantitative measure of the degree to which a system, component or process possesses a given attribute (Fenton & Pfleeger, 1997). Software metrics information is very much helpful in reverse engineering process.

Based on the facts discussed above, this work proposes a novel approach which is .net based, model driven and exploits software metrics, for migration from legacy software systems to web services. Software maintenance, re-engineering, and reuse involving large software systems is complex, costly and risky mainly because of the difficult and time-consuming task of program comprehension (Systa et al., 2000). Hence this approach deals the software system at macro-level or high level abstraction of the legacy system. The key objective of this approach is to make an attempt to provide solution for migration process from legacy systems to web services with lesser effort and complexity. This work uses black box approach and so the process is easy to implement and improve it in future. This approach is suitable for software for any business application because the vital strength of web services is that they provide mechanism for seamless interaction between business-to-business and business-to-customer in business enterprises.