However, while general theories and frameworks exists for decision analysis, the complexity and diversity of IS problems necessitate
research and development of frame-works and models specific to the class of decision problems that IS managers face.
3 The papers
In this special issue we present eight papers that present a range of approaches and address a wide range of IS decision problems. In general the papers can be classified into two categories, frameworks for decision analysis and decision models. One of the papers presents a conceptual framework; five of the papers present structured decision analysis
frameworks, and three present decision-theoretic based models. While all the papers follow the design science paradigm of research, the decision framework papers present empirical cases, and the decision-theoretic papers present demonstrations of analysis using the models.
The Samoilenko paper (Information Systems Fitness and Risk in IS
Development: Insights and Implications from Chaos and Complex Systems Theories) outlines a framework and principles for analyzing IS fitness and risk based on chaos and complexity theory. Samoilenko approach is more in the tradition of appreciative decision making, where the focus is on ways of thinking to help the decision maker appreciate the problem situation. Aydin and Bakker (Analyzing IT Maintenance Outsourcing Decision from a Knowledge Management Perspective) also followthis tradition but from an empirically grounded perspective outlining a framework for decision analysis of knowledge management issues in IS outsourcing. They focus mainly on strategies for interrogating the problem domain and structuring the decision problem. Alaranta and Henningsson (An Approach to Analyzing and Planning Post-Merger IS Integration: Insights from Two Field Studies) outline a framework and approach for post-merger information systems integration planning. Post-merger IS integration is a complex multidimensional problem that is challenging many IS managers. Alaranta and Henningsson discuss the key decisions of the planning process and suggest strategies for approaching them. An important feature of their approach is its grounding in empirical case studies of favorable and unfavorable strategies. The Scheepers and Scheepers (A Process-focused Decision Framework for Analyzing the Business Value Potential of IT Investments) framework focuses on analyzing IT investments from the perspective of business value creation. These authors develop a model for exploring the business value potential of IT at the business process level; a challenging undertaking necessary for cost-benefit analysis. The last of this category is that of Barclay (Towards An Integrated Measurement of IS Project Performance: The Project Performance Scorecard), who presents a
framework and approach for evaluating project performance based on
existing theoretical models of IS success and the Balanced Scorecard. She focuses on defining dimensions of project measurement that are of interest to different stakeholders and a process for eliciting preferences.
The three decision-theoretic papers also vary in topics
that they cover. Like Barclay, Plaza (Team Performance and Information System Implementation Application of the Progress Curve to the Earned Value Method in an Information System Project) is concerned with IS
project performance but comes to the issue from a different perspective. Plaza is interested in predicting implementation times (and cost) for large scale IS projects and proposes a decision model based on the earned value method and the learning curve. Rao and Osei-Bryson (An Approach for Incorporating Quality-Based Cost–Benefit Analysis in Data Warehouse Design) focus on an aspect of data warehouse design where the major concern is the determination of the data that are to be produced and stored in the data warehouse. They present a cost-benefit model that
incorporates quality issues in data warehouse design.Finally Turetken (Is Your Back-Up IT Infrastructure in a Safe Location?) presents a multi-criteria decision model for location of the IT infrastructure for business continuity planning.
4 Contribution of this issue
This issue of ISF makes a contribution to theory and practice of IS management from the following perspectives: (1) The papers present
frameworks and models that have immediate application to various classes of IS decision problems. (2)The papers present possibilities for further research into decision models for the problems that the authors have addressed. However, this research can evolve along different lines: (a) the development of decision support systems for the addressed problems; (b) other approaches or techniques that might be applicable for extending the breadth and depth of the current approaches; (c) alternative approaches can be proposed for the set of problems and comparative
analysis can be conducted.We wish to express our appreciation to all the authors who submitted papers.
We also wish to express our gratitude to all the reviewers who diligently reviewed the papers in order to ensure that that there was appropriate quality and fit.
The Application Reseach of Mixed Program Structure based on
Client-Server,Browser-Server and Web Service
I. INTRODUCTION
During the development process of computer application design and development, multiple program structure mode have turned up, such as common C/S (Client/Server) mode and B/S (Browser/Server) mode; C/Ss
(multilayer and multiserver Client/Server application structure) mode and B/Ss(multilayer and multi-server Brower/Server application structure), evolving from the above two modes; as well as other modes.
These application structures with different modes have respective
characteristics and all of them have very broad application. For example, C/S mode enjoys a wide application in earlier enterprise management information system and B/S mode is extensively applied in modern E-commerce websites.
Along with the development of computer and network technology,
application of mixed application structure mode,based on the aforesaid modes and Web Service, has developed quickly. Typical instances are Tencent QQ message service and Thunder consultation service as well as others. This text discusses realization principle and characteristics of C_B/S mixed application system structure mode and analyzes application and realization of C_B/S mode with examples.
II. REALIZATION PRINCIPLE OF C_B/S STRUCTURE MODE
C_B/S mode is a mixed application structure mode.Viewing from program appearance, application program of C_B/S mode has the program interface of common customized client. However, different from common C/S mode
programs,partial functions of C_B/S mode application program are realized by B/S mode or integrated Web Service, which indicates that C_B/S mode is a new program structure realized through C/S, B/S and Web Service.
Realization methods of C_B/S mode application are mainly two types.
A. Webpage integrated type
Webpage integrated type indicates that client of C_B/S program realizes partial functions through acquiring customized webpage directly from
corresponding website during execution. The process is shown in Figure 1.
C_B/S mode program realized by webpage integrated type generally
integrates one or several browser component (s) in client program. The mode visiting website and acquiring data through integrated browser
components is similar as directly visiting website through common browser (such as IE). The difference is that client of C_B/S program is customized which could thereby integrate more specific functions.
B. Web Service integrated type
Compared with webpage integrated type, Web Service integrated type could have no browser components within application client and data required by partial program functions are realized interactively with specific Web Service.Web Service provides information to outside in XML format and client program could send specific parameters to Web Service to acquire data qualified for designated conditions.Realization process of this method is shown in Figure 2.
Figure 1. Webpage integrated C_B/S mode
Figure 2. Web Service integrated C_B/S mode
III. CHARACTERISTICS OF C_B/S MODE
Owing to integration of structures of the three modes: C/S,B/S and Web Service, application program of C_B/S mode has characteristics partly of the above three modes which are represented specifically in following aspects.
A. High security
Comparatively speaking, application program of C/S mode
deploys client program independently and thereby limits user within specific range, which prevents usage from illegal users to some extent and has comparative high security. Many enterprise application programs in early stage, such as ERP,adopt this mode partly because of this
characteristic of C_B/S mode application program. C_B/S mode application program is based on client program of C_B/S mod and thereby inherit this advantage of C/S mode.
B. Higher preprocessing performance on client
This is also the advantage that C/S mode inherits from C_B/S mode. C_B/S programs on client are able to accomplish certain data preprocessing
functions, thereby reducing load pressure on server and enhancing entire performance of application system.
C. Easy for deployment
Compared with C/S mode, B/S and Web Service has the advantage of
convenient deployment of application program.Owing to requirement only on client computer to install universal network browser program (such as IE, FireFox and others) and customized client program is not necessary, all application functions could be realized on the server. Therefore,at the time of deployment and upgrade, there’s only the demand to deploy and upgrade the server, which is more convenient for deployment. C_B/S mode can integrate B/S webpage in client programs and these functional modules also can be realized through programs on the server. While upgrading, it can be accomplished only by re-deploying programs on the server, thereby also having better convenience for deployment.
D. Flexible application interface style
Compared with client program interface, webpage modeled application interface has more flexible style, stronger expressive force, which is more favorable for designers to give full play to their advantages. Therefore, C_B/S mode application program of integrated B/S mode could realize more flexible and diversified interface styles.
C_B/S mode application, however, has many shortages. In addition to
certain problems inherited correspondingly from C/S mode upon deployment and upgrade, main problem is that C_B/S mode program is difficult to solve data integration problem between client programs and browser
components.Because common data in client programs are stored and deployed