Research And Realization Of Meta-modeling Tool Based On MDA In Telecommunications

The rapid development of information age came with the appearance of VLSI. Computer technology has penetrated into every filed of life simultaneously. And software is gradually becoming the"nerve center"of global economy. However, the traditional software development patterns are increasingly difficult to cope with the serious problems of complexity, diversity and variability in the process of software development. Moreover, excellent software products are not adequate to compare with constantly renewed hardware implementation techniques. The methodology of Object-oriented Programming (OOP) only mitigates the software crisis in a certain extent rather than solve it completely. Therefore, current researches focus on how to develop software of good extensible performance with effective patterns. And then Model Driven Architecture (MDA) which is proposed by Object Management Group (OMG), the largest organization of software industry standard around the world, comes into being.MDA is a new specification for using modeling architecture in software development. Notably, it is a new approach to alleviate pressure facing the software industry. Thereby, some essential techniques and criteria are introduced in order to prepare for the industrialization of software in MDA. The aim of MDA is to insulate business requirements of system from concrete implementation techniques. And during the development process, a series of system models that belong to different abstraction levels are produced. These models are divided into two categories; namely, Platform Independent Model (PIM) and Platform Specific Model (PSM). The former concentrates on business logic regardless of platform-related details. In addition, fully-specified PIM can enable intellectualized transformation which enhances interoperability of system. The key of MDA is that model plays a very important role in software development lifecycle. The whole development process is driven by the behavior of modeling. Through raising abstraction level of development, MDA makes the abstract model not influenced by specific implementations, which thereby increases the extensibility, portability and maintainability of software, as well as improves efficiency of development and prolongs software life cycle.Meta-modeling theory is the cornerstone of MDA framework. In the theory, model is formal specification about the structure, function, behavior and performance of system. And meta-model is model of a model that captures its essential properties and features. Hence MDA is based on the concept of model which depends on meta-model. Clearly, there is a close relationship between model and meta-model. Compared to traditional modeling method, meta-modeling is a higher level modeling approach in more abstract expression way. In a sense, meta-modeling defines a modeling language to achieve the consistency of data and logic, so design issues can be discussed on higher abstraction level. It is more than 10 years since the concept of meta-modeling was introduced into software engineering filed. Since then meta-modeling method, as well as technical standards of meta-modeling, continues to be improved and perfected. Finally, OMG established unified meta-layer; namely, meta-modeling framework. There are four layers from down to top that are M0 layer, M1 layer, M2 layer and M3 layer. From the dialectical viewpoint, every layer is an abstraction of former one, as well as an instance of the latter. There are some core criteria to support meta-modeling theory, such as Meta Object Facility (MOF), Query/Views/Transformations (QVT), Unified Modeling Language (UML), and Object Constraint Language (OCL).According to related theories, the process of meta-modeling is as follows: In the beginning, it is necessary to construct a kind of meta-modeling language to describe meta-model accurately, which includes the definitions of its abstract syntax, concrete syntax and semantics. Then, meta-models are created in this language. At last, models are generated through the description of various elements in meta-models. The purpose of meta-modeling is to establish meta-model so as to satisfy the character of special fields, to support the transformation and interoperability among models, and to provide well-defined meta-model for the next stage of modeling. In this way, meta-models, which have the characteristic of higher extensibility and cross-platform, can communicate with other parts of system via the standard mode.Currently, with the rapid development of telecommunication technologies, the huge diversity of network devices and the increasing complexity of network topology put the design of network management software in great quandary. It has brought big challenges due to frequent changes of software requirement. To contend with this problem, research addresses both methods and tools to support the changes. Communication Net Software Platform (CNSP) is a network management platform that aims to manage telecom requirement changes based on MDA. As a subsystem of CNSP, meta-modeling tool applies meta-modeling theory to telecom field. As a result, meta-models in a domain specific language that provides a highly specialized set of domain concepts are created, and all kinds of operations and management on meta-models are provided at the same time by using the meta-modeling tool.It is well known that well-designed framework is in favor of code reuse and system stability. In order to design an extensible and manageable framework, the architecture of meta-modeling tool is divided into three layers: presentation layer, business logic layer and storage layer. First, presentation layer is used for user interaction whose main functionality contains building, modifying, deleting and other operations on meta-model. There are three modules in this layer: Navigator View, Editor View and Manager View. Second, business layer is used to deploy Enterprise Java Bean Component. Component and service can, of course, be dynamically deployed at runtime. It is an interface between presentation and storage layer. Third, storage layer is used to save meta-model information in a distributed environment. On the one hand, meta-modeling tool can be installed on clients in different area for cooperative work. On the other hand, database and application server are installed on center server for centralized management. Besides, this layer also involves the persistence of xKL information (the textual syntax of meta-model transformed by diagrammatic syntax).By and large, it is profound significant to research how to establish meta-model with rich information and static and dynamic semantics. Applying aforementioned meta-modeling theory to the large-scaled and sophisticated telecom field, abstractions and related concepts are distilled from various network management requirements. And then the system is represented in a unified and meaningful way, which enhances the interoperability and generality among subsystems, as well as decreases the amount of information isolated islands. Practice has proved that applying meta-modeling tool to telecom field is an effective means to support network management, which shows the superiority of MDA in certain degree.