Modeling And Analyzing Metamodel Of Network Software Requirement Based On Web Service

Being disposed in network environment, the network software is a kind of special service-oriented computation and super large-scale complicated software system. The requirement engineering of network software is facing many problems because of its dynamic topological structure, uncertainty of users and the increasing requirements. However, lacking enough support in service-oriented computation currently, modeling methods of software requirement cannot get Web services resource distributed in network together to improve development efficiency of information system effectively. Meanwhile, being deployed in the network environment, Web services are obviously to be influenced by situational factors such as the environment, platform, etc., and improving users' experience quality and regarding user as the centre are becoming one of the key goals that the software system is being chased.RGPS meta-model frame was proposed by 973 Project (Major Project of Chinese National Programs for Fundamental Research and Development) group of Software Engineering Institute of Wuhan University. RGPS meta-model frame pays close attention to situation impacting on requirement modeling and restraint. RGPS meta-model frame includes 4 layers, which are role (R) layer, goal (G) layer, process (P) layer and service (S) layer. There are relationships in coordination between 4 layers of RGPS: the role bears corresponding role's goals, and the participant has a personal preferred goal; the process can achieve the functional goal, and it can also impel the realization of a non-function goal; Web service can realize the process. Domain-oriented O-RGPS utilizes the domain ontologies (O) to offer semantic support for domain R, G, P, S model. The modeling course of requirements based on RGPS is begun on the time when analyzing the institutional framework of the requirements problems space, and is ended when it get the solution based on service.Requirement verification is one important phase of the software requirement course, and the requirements without verification will bring great risk for the project. To support the verification of Web service specification of RGPS requirement meta-model, every level of RGPS is distinctly described in OWL-S(Ontology Web Language for Service), and is formally modeled with Petri nets and F-logic, so that the consistency of semantic of Web services is verified. Based on the description of semantic web service in OWL-S, this paper discusses the composition of semantic Web service of RGPS meta-model frame, its dynamic analytical Petri nets methods, and its static analytical DL and F-logic methods, mainly including several works as follows,(1) Proposes formally expressing and analytical methods of every level of software requirement framework. The internal structure of every layer of RGPS, and the related consistency problems among layers are analyzed.We also formally modeled the requirement specifications of every layer of RGPS by Petri nets and F-logic. We turn into the ontologies by relevant tools after obtaining the requirements with UML. The requirements of every layer of RGPS are presented with domain ontologies of O-Net. In this way, the verification problem of the requirements obtained by every layer of RGPS can be turned into means by which express in unison with the ontologies then formally model O-Net and verify it. This has reduced the complexity of analyses greatly, and raised the efficiency of it.(2) For dynamic model, application logic of Web service described in OWL-S is firstly transformed into Petri nets ontologies model expressed in the form of PNML, then model the composite processes of the semantic Web service with Petri nets, and analyze its dependency, complexity, providing verification theorems and algorithms in relevant properties such as reachability, liveness.(3) Depict the static model of OWL-S with F-logic formally. An F-logic model is designed in order to verify OWL-S ontologies, and its globe attributes and frame are expressed as F-logic classes and formula formally. At the same time, axioms, deductive rules and theorems which can verify the consistency, satiability and other relative properties of the model are given, in order to analyze the model of OWL-S, and deduce the tasks that OWL-S support.(4) A verification tool that integrates the checking of the static model and dynamic model has been implemented as an organic whole. The verification tool can provide effective verification of Web services described in OWL-S. We describes and composites Web service specification of RGPS in OWL-S, transformming OWL-S file into PNML form, looking Petri model as dynamic verification models, and taking Pellet and Flora-2 as deductive engines of static mode, then has realized analysis and verification of the model formally by tool.The aforesaid work makes for the solution of service composition of RGPS meta-model frame and formal verification. The verification of the model has overcome the complexity during the verification of requirement and overcome experience operation effectively, and reduces risk of the project effectively.