The global community faces many pressing and uncertain challenges like pandemics and global climate change. Information technology (IT) infrastructure has become the enabler to addressing those ...challenges. Unfortunately, IT decoupling has distracted and weakened the international community’s ability to handle those challenges.
This article initiates an open-source computer system (OSCS) initiative to tackle the challenges of IT decoupling. The OSCS movement is where open-source software converges with open-source hardware. Its essential is to utilize the inherent characteristics of a class of representative workloads and propose innovative abstraction and methodology to co-explore the software and hardware design spaces of high-end computer systems, attaining peak performance, security, and other fundamental dimensions. I discuss its four challenges, including the system complexity, the tradeoff between universal and ideal systems, guaranteeing quality of computation results and performance under different conditions, e.g., best-case, worst-case, or average-case, and balancing legal, patent, and license issues.
Inspired by the philosophy of building large systems out of smaller functions, I propose the funclet abstraction and methodology to tackle the first challenge. The funclet abstraction is a well-defined, evolvable, reusable, independently deployable, and testable functionality with modest complexity. Each funclet interoperates with other funclets through standard bus interfaces or interconnections. Four funclet building blocks: chiplet, HWlet, envlet, and servlet at the chip, hardware, environment management, and service layers form the four-layer funclet architecture. The advantages of the funclet abstraction and architecture are discussed. The project’s website is publicly available from https://www.opensourcecomputer.org or https://www.computercouncil.org.
Currently, in simulation there is a trend towards using the distributed software tools, particularly ones, which are using cloud technologies and the Internet. The article considers a simulation ...educational tool, implemented as a web application using the Java language with special Java class library developed for simulation. It is focused on a discrete event approach to modeling, similarly to the GPSS language, and intended for queuing systems simulation.The structure of the models obtained using this class library is similar to that of the GPSS language models. Also, the simulation language interpreter similar to GPSS is created using this class library, with some differences in the individual statements.Simulation experiments are performed on the server-side, and on client-side you must use a browser with standard functions to enter the source code into HTML-created form. Mobile devices can be used as clients. The source code of a model can be represented both in the Java language using a class library and in the language similar to GPSS.The simulation system implements functions especially for educational process. For example, there is possibility for a student to upload learning materials on the server, send developed software and reports of test control to the teacher via the Internet, and receive a detailed assessment of their results from the teacher. Also detailed results of passed tests in learning modules are entered, and some other functions are implemented in the system.As examples, the article considers models of the m/M/n/0 type queuing system in Java with a class library, and in the language similar to GPSS, shows simulation results, and presents the analytical model and calculations for this system. Analytical calculations proved that the modeling system is useful, as it overlaps simulation results with the acceptable error. Some approaches to the interaction with students through the Internet, used in modeling environment, can find application in teaching other subject matters.
The transmission rate via radio increases to transmitting frequency increment. The higher frequency the higher transmission rate. Video traffics require radio with large bandwidth. This requirement ...may be fulfilled by the use of millimetre radio transmission on 20 GHz. However, radio signal on millimetre band decreases significantly in presence of rain mainly caused by link attenuation. This paper evaluates the performance of video transmission on 20 GHz in presence of rain on tropical environment. As various layers techniques are available, some techniques such as APA, Java Servlet Alias (JSPA), Digital Subtraction Angiography (DSA) and mac-application layer scheduling are implemented to help radio dealing with rain attenuation. The evaluation results through designed simulations proves that the video quality degrades significantly to rain. The combined technique is able to increase video quality, namely; physical technique up to 0.395 dB, MAC scheduler up to 6.5dB and upper layer technique achieves 1.17 dB.
It was the key factor that Servlet thread had been take up. it was affected the pushlet performance, in order to solve this problem, we introduced of Servlet3.0 asynchronous features, we need to ...transform the Pushlet, concurrent performance was improved after optimization, it can to run with high performance in the high number of concurrent users, a long time.
It is very difficult to find the minimum route to travel in amusement park navigation. A searching system for visitors would be useful. Therefore, we constructed a system to find the route with the ...minimum total traveling time. Facility visitors can employ this system on a smart phone. The system is composed of Java and a Java Servlet. We conclude that our system is useful and can greatly shorten travel time within a typical amusement park.
Pro JSP 2 Brown, Simon; Dalton, Sam; Jepp, Daniel ...
2005
eBook
Pro JSP 2, Fourth Edition is the only comprehensive guide and reference to cover JSP 2 and 2.1 yet. It equips readers with the tools, techniques, and understanding they need to develop web ...applications with JSP and Java servlets. The new features of the JSP 2.0, 2.1 and Servlet 2.4 specifications make developing web applications easier than ever before. With 2.1, readers can integrate and use the latest JavaServer Faces (JSF) 1.2 in J2EE 5 with JSP. Also, the JSP Expression Language (EL) provides a simple language for creating JSP pages and tags. In addition, by also using the JSP Standard Tag Library (JSTL), readers should never have to use a Java scriptlet or write spaghetti code again. Beyond covering the JSP and Servlet APIs, this book shows how to choose and implement the best persistence option for your web applications, how to secure web sites against malicious attack and accidental misuse, how to improve the performance and scalability of JSP pages, and how to architect and design applications to be reliable, stable, and maintainable through the use of design patterns and best practices. Finally, no JSP book would be complete today without looking at the role that open source projects such as Ant, Struts, XDoclet, JUnit, and Cactus can play in making web development even easier.
Server Design of Personal Cloud Sync Storage System Xue, Xiao Qing; Li, Li Fang; Zhang, Fu ...
Applied Mechanics and Materials,
02/2014, Volume:
511-512, Issue:
Sensors, Mechatronics and Automation
Journal Article
Peer reviewed
This paper introduces the server design of a personal cloud sync storage system based on Android mobile terminal, including system architecture, workflow and module design. According to the ...application characteristics of personal cloud, this thesis selects Servlet as the core development technology of server-side system, describes the development process of the personal cloud server based on Tomcat container and establishes a secure connection between the mobile terminal and the personal cloud server center. Under the LAN environment, the server system has successfully completed the function module of the test and assembly verification test. Test results show that the whole system runs in good condition and has certain applicative value.
This article proposes a novel unified IP Multimedia Subsystem (IMS) authentication architecture that extends the scope of IMS by allowing it to offer users different IMS-based services even beyond ...their own domain. The architecture reduces the burden of both end users and service providers by a Single Sign-On (SSO) feature. We describe how we have implemented our proposed authentication architecture for a tentative IMS service, Movie-on-Demand (MoD), by creating SIP proxies with additional SAML and HTTP message-handling intelligence and integrating them with an open-source implementation of a full IMS environment, from client to Application Server (AS). The relation between call setup time and network latency has been mathematically modelled. The developed mathematical model is validated by deploying a simplified implementation in the public Internet and observing call setup time and delay. The proposed architecture is further extended for a generalized scenario where the identity provider (IdP) could be managed by a third-party other than the IMS core operator. The authentication architecture proposed in this paper creates opportunities for operators to build partnerships with the service providers, and thus supports the emergence of new business models.
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