Middleware facilitates the development of distributed systems by accommodating heterogeneity, hiding distribution details and providing a set of common and domain specific services. It plays a central and essential role for developing distributed systems. However, middleware is considered a mean rather than core elements of development process in the existing distributed systems software process. This paper explains the concept of middleware by categorizes middleware and analysis the problems

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... current middleware architectures. It also extracts three essential non-functional requirements of middleware and proposes a middleware-based distributed systems software process. The proposed software process consists in five phases: requirements analysis, design, validation, development and testing. The characteristics of middleware are considered in the entire software process. Component-Based Software Engineering, Separation of Concerns, Model-Driven Architecture, formal methods and Aspect Oriented Programming are five active research areas that have been around for several years now. In this paper, we present how these five paradigms can be put together in the context of a new software development method and we show how they can complement each other at different stages in the development life-cycle of middlewaremediated applications. 29 design. Doing so would in fact contradict the design goals of middleware, which aim to make them broadly applicable to a wide range of domains, i.e., general purpose. 30 illustrated on a producer/consumer system implemented using the active object pattern in middleware. And, broader impacts of the methodology for middleware specialization are also described. Milan J. et al. in [5] deal with middleware services required for the efficient deployment and operation of distributed smart cameras. They focus on services for autonomous and dynamic reconfiguration and develop the services for dynamic reconfiguration using policies. Policies help to specify rules for the reconfiguration process. By evaluation the policy the new task-level configuration of the network is computed. The reconfiguration is implemented using mobile agents in order to achieve a flexible and scalable middleware service. Amogh K. et al. in [6] described GTQMAP (Graph Transformation for QoS MAPping) model driven engineering tool chain that combines domain specific modeling, to simplify specifying the QoS requirements of DRE systems intuitively, and model transformations, to automate the mapping of domain-specific QoS requirements to middleware-specific QoS configuration options. The automation capabilities of GT-QMAP in the context of three DRE system case studies are evaluated.