Self-reconfigurable, intrusion-tolerant, web-service composition framework

The Internet has provided an opportunity for businesses to offer their services as Web Services (WSs). WSs are used to implement Service Ori-ented Architecture (SOA). They enable composition of independent services with complementary functionalities to produce value-added services, which results in less development effort, time consumption and cost, enabling com-panies and organizations to implement their core business only and out-source other service components over the Internet, either pre-selected or on-the-fly. Simple Object Access Protocol (SOAP) based WSs are at risk of se-curity vulnerabilities related to their specific implementation technologies such as Extensible Markup Language (XML) as well as those of their under-lying platforms (e.g., operating systems and frameworks) and their applica-tions (e.g., vulnerability to SQL Injection attacks). Cyber-attacks on WSs may cause unavailability, loss of confidentiality and/or integrity as well as signifi-cant monetary penalties. Security issues become more challenging when Off-The-Shelf Web Services (OTSWSs) are used since they are beyond the con-trol of their clients. The central question underlying this work is: Can a self-reconfigurable Intrusion-Tolerant Web Ser-vice, implemented using N-version programming and diversity formed by composing Off-The-Shelf Web Services that are selected through penetration testing, Principal Component Analysis, and Cluster Analysis process-es mitigate XML-related security vulnerabilities? While aiming to answer the above question, this dissertation presents a novel framework to increase dependability by constructing an Intrusion-Tolerant Web Service (ITWS) in which N-version programming and diversity, formed by composing SOAP-OTSWSs, is used. It describes how penetration testing can be used as a measure of security vulnerabilities of available SOAP-OTSWSs (that offer the required functionality) and the resultant ITWS, how Principal Component Analysis (PCA) and Cluster Analysis (CA) and be utilized to group the SOAP-OTSWSs based on their security vulnerabilities diversity and how a further penetration testing on each group of diverse SOAP-OTSWSs can be used to select the optimal set (most secure among the groups) for construction of ITWS. This dissertation also demonstrates how the dynamic reconfiguration of ITWS, created in Business Process Engineering Language (BPEL), can be enabled using a combination of BPEL constructs and Java as BPEL exten-sion approach and using only Java as BPEL extension approach. The novelty of the work presented in this dissertation is twofold. On the one hand, it is security informed and on the other hand, it demonstrates the use of Java (as BPEL 2.0 extension) to implement self-reconfigurable composite WS. It has the advantage of, at the same time, facilitating a de-pendable service to users and exploiting existing standard technologies. This work also assesses the effectiveness of the proposed solutions through vari-ous case studies and discusses the implications of the proposed framework.