Being a popular runtime infrastructure in the era of Internet, middleware provides more and more services to support the development, deployment and management of distributed systems. At the same time, the reliability of middleware services has a significant impact on the overall reliability of the system. Different services have different impacts and different service fault-tolerance solutions have different costs and risks. Therefore, the identification of the services that greatly affect the whole system reliability is the major obstacle to achieving reliable middleware-based systems. In this paper, we present an analytical framework to automatically reason and quantify such impacts when deploying the target system. In this framework, faults are represented by exceptions in modern programming languages; service failures are simulated by software fault injection; reliability impacts are measured by scenarios. This framework is demonstrated on multiple JEE application servers, including JBoss, JonAS and PKUAS. The experiments on two JEE blueprint applications, namely JPS and ECperf, show the feasibility, the applicability and the usability of this framework.

Runtime software architectures (RSA) are architecture-level, dynamic representations of running software systems, which help monitor and adapt the systems at a high abstraction level. The key issue to support RSA is to maintain the causal connection between the architecture and the system, ensuring that the architecture represents the current system, and the modifications on the architecture cause proper system changes. The main challenge here is the abstraction gap between the architecture and the system. In this paper, we investigate the synchronization mechanism between architecture configurations and system states for maintaining the causal connections. We identify four required properties for such synchronization, and provide a generic solution satisfying these properties. Specifically, we utilize bidirectional transformation to bridge the abstraction gap between architecture and system, and design an algorithm based on it, which addresses issues such as conflicts between architecture and system changes, and exceptions of system manipulations. We provide a generative tool-set that helps developers implement this approach on a wide class of systems. We have successfully applied our approach on JOnAS JEE system to support it with C2-styled runtime software architecture, as well as some other cases between practical systems and typical architecture models.

Access control is a common concern in most software applications. In component-based systems, although developers can implement access control requirements (ACRs) by simply declaring role-based access control configurations (ACCs) of components, it is still difficult for them to define and evolve ACCs accurately implementing ACRs due to the gap between the complex high-level ACRs and the voluminous ACCs enforced by underlying middleware platforms, and the ad hoc mistakes of human. This paper introduces and clarifies the concept of accuracy of ACCs relative to ACRs, and presents a set of metrics and algorithms which can be used to automatically evaluate and improve accuracy of ACCs by evaluating and reconfiguring the software architecture with ACCs. We apply our achievements in a composed e-shop application.

System management is becoming increasingly complex and brings high costs, especially with the advent of cloud computing. Cloud computing involves numerous platforms often of virtual machines (VMs) and middleware has to be managed to make the whole system work cost-effectively after an application is deployed. In order to reduce management costs, in particular for the manual activities, many computer programs have been developed remove or reduce the complexity and difficulty of system mamnagement. These programs are usually hard-coded in languages like Java and C++, which bring enough capability and flexibility but also cause high programming effort and cost. This paper proposes an architecture for developing management programs in a simple but powerful way. First of all, the manageability of a given platform (via APIs, configuration files, and scripts) is abstracted as a runtime model of the platform’s software architecture, which can automatically and immediately propagate any observable runtime changes of the target platforms to the corresponding architecture models, and vice versa. The management programs are developed using modeling languages, instead of those relatively low-level programming languages. Architecture-level management programs bring many advantages related to performance, interoperability, reusability, and simplicity. An experiment on a real-world cloud deployment and comparisonwith traditional programming language approaches demonstrate the feasibility, effectiveness, and benefits of the new model based approach for management program development.

To meet the needs of computing in the Internet environment, the Internetware software paradigm provides a set of technologies that support the development of applications with characteristics that are autonomous, cooperative, situational, evolvable, emergent, and trustworthy.