DATABASE DEVELOPMENT LIFE CYCLE

A software development life cycle model (SDLC) consists of a set of processes (planning, requirements, design, development, testing, installation and maintenance) defined to accomplish the task of developing a software application that is functionally correct and satisfies the user’s needs. These set of processes, when arranged in different orders, characterize different types of life cycles. When developing a database, the order of these tasks is very important to efficiently and correctly transform the user’s requirements into an operational database. These SDLCs are generally defined very broadly and are not specific for a particular type of application. In this paper the authors emphasize that there should be a SDLC that is specific to database applications. Database applications do not have the same characteristics as other software applications and thus a specific database development life cycle (DBDLC) is needed. A DBDLC should accommodate properties like scope restriction, progressive enhancement, incremental planning and pre-defined structure.Software Development, Database, DBMS, lifecycle model, traditional lifecycles

Interesting viewpoints to those who will put Ada into practice

Ada will most probably be used as the programming language for computers in the NASA Space Station. It is reasonable to suppose that Ada will be used for at least embedded computers, because the high software costs for these embedded computers were the reason why Ada activities were initiated about ten years ago. The on-board computers are designed for use in space applications, where maintenance by man is impossible. All manipulation of such computers has to be performed in an autonomous way or remote with commands from the ground. In a manned Space Station some maintenance work can be performed by service people on board, but there are still a lot of applications, which require autonomous computers, for example, vital Space Station functions and unmanned orbital transfer vehicles. Those aspect which have come out of the analysis of Ada characteristics together with the experience of requirements for embedded on-board computers in space applications are examined

A comparative analysis of maintainability approaches for web applications

Web applications incorporate important business assets and offer a convenient way for businesses to promote their services through the internet. Many of these web applications have evolved from simple HTML pages to complex applications that have high maintenance cost. The high maintenance cost of web applications is due to the inherent characteristics of web applications, to the fast internet evolution and to the pressing market which imposes short development cycles and frequent modifications. In order to control the maintenance cost, quantitative metrics and models for predicting web applications' maintainability must be used. Since, web applications are different from traditional software systems, models and metrics for traditional systems can not be applied to web applications. The reason for that is that web applications have special features such as hypertext structure, dynamic code generation and heterogenousity that can not be captured by traditional and object-oriented metrics. In this paper, we will provide a comparative analysis of the different approaches for predicting web applications

Stable Structures for Distributed Applications

For distributed applications, we define the linear, tree and graph structure types with different variants and modalities to aggregate them. The distributed applications have assigned structures that through their characteristics influence the costs of stages for developing cycle and the costs for exploitation, transferred to each user. We also present the quality characteristics of a structure for a stable application, which is focused on stability characteristic. For that characteristic we define the estimated measure indicators for a level. The influence of the factors of stability and the ways for increasing it are thus identified, and at the same time the costs of development stages, the costs of usage and the costs of maintenance to be keep on between limits that assure the global efficiency of application. It is presented the base aspects for distributed applications: definition, peculiarities and importance. The aspects for the development cycle of distributed application are detailed. In this article, we alongside give the mechanisms for building the defined structures and analyze the complexity of the defined structures for a distributed application of a virtual store.distributed applications, data structures, costs, software quality

Building an experience factory for maintenance

This paper reports the preliminary results of a study of the software maintenance process in the Flight Dynamics Division (FDD) of the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC). This study is being conducted by the Software Engineering Laboratory (SEL), a research organization sponsored by the Software Engineering Branch of the FDD, which investigates the effectiveness of software engineering technologies when applied to the development of applications software. This software maintenance study began in October 1993 and is being conducted using the Quality Improvement Paradigm (QIP), a process improvement strategy based on three iterative steps: understanding, assessing, and packaging. The preliminary results represent the outcome of the understanding phase, during which SEL researchers characterized the maintenance environment, product, and process. Findings indicate that a combination of quantitative and qualitative analysis is effective for studying the software maintenance process, that additional measures should be collected for maintenance (as opposed to new development), and that characteristics such as effort, error rate, and productivity are best considered on a 'release' basis rather than on a project basis. The research thus far has documented some basic differences between new development and software maintenance. It lays the foundation for further application of the QIP to investigate means of improving the maintenance process and product in the FDD

Security assessment of open source third-parties applications

Free and Open Source Software (FOSS) components are ubiquitous in both proprietary and open source applications. In this dissertation we discuss challenges that large software vendors face when they must integrate and maintain FOSS components into their software supply chain. Each time a vulnerability is disclosed in a FOSS component, a software vendor must decide whether to update the component, patch the application itself, or just do nothing as the vulnerability is not applicable to the deployed version that may be old enough to be not vulnerable. This is particularly challenging for enterprise software vendors that consume thousands of FOSS components, and offer more than a decade of support and security fixes for applications that include these components. First, we design a framework for performing security vulnerability experimentations. In particular, for testing known exploits for publicly disclosed vulnerabilities against different versions and software configurations. Second, we provide an automatic screening test for quickly identifying the versions of FOSS components likely affected by newly disclosed vulnerabilities: a novel method that scans across the entire repository of a FOSS component in a matter of minutes. We show that our screening test scales to large open source projects. Finally, for facilitating the global security maintenance of a large portfolio of FOSS components, we discuss various characteristics of FOSS components and their potential impact on the security maintenance effort, and empirically identify the key drivers

Towards the Quality Factor of Software Maintenance Process: A Review

Software maintenance (SM) is classified as the common process of modifying a system or software product once it has been delivered to user. Different type of process applied to different type of applications and in certain stages of the processes involve adding new components to the existing system. Software maintenance process is a series of actions taken to overcome changes during the maintenance phase. To ensure the sustainable quality of software product throughout the software life cycle, a good mechanism in software maintenance process should be implemented. Most organization nowadays depend on software products to run their business operations. Thus, it is crucial to ensure the software applications operating in the organization are sustainable while preserving its quality in a long run. The kick-off study starts with identifying the quality factors related to maintainability dimension that affected software maintenance process. A comprehensive literature study is conducted to find related processes within maintainability sub-factors. The identified factors will be evaluated by practitioners who involve in maintaining process. The maintainer personnel help to prioritize the task and eliminate the insignificant activities during maintenance process. This paper focuses on maintainability quality factors and its sub-characteristics impact on software maintenance process

The Verification of Temporal KBS: SPARSE - A Case Study in Power Systems

In this paper we present VERITAS, a tool that focus time maintenance, that is one of the most important processes in the engineering of the time during the development of KBS. The verification and validation (V&V) process is part of a wider process denominated knowledge maintenance, in which an enterprise systematically gathers, organizes, shares, and analyzes knowledge to accomplish its goals and mission. The V&V process states if the software requirements specifications have been correctly and completely fulfilled. The methodologies proposed in software engineering have showed to be inadequate for Knowledge Based Systems (KBS) validation and verification, since KBS present some particular characteristics. VERITAS is an automatic tool developed for KBS verification which is able to detect a large number of knowledge anomalies. It addresses many relevant aspects considered in real applications, like the usage of rule triggering selection mechanisms and temporal reasoning

Communication Paradigms for High-Integrity Distributed Systems with Hard Real-Time Requirements

The development and maintenance of high-integrity software is very expensive, and a specialized development process is required due to its distinctive characteristics. Namely, safety-critical systems usually execute over a distributed embedded platform with few hardware resources which must provide real-time communication and fault-tolerance. This work discusses the adequate communication paradigms for high-integrity distributed applications with hard real-time requirements, and proposes a restricted middleware based on the current schedulability theory which can be certified and capable to obtain the required predictability and timeliness of this kind of systems