Client-server Applications Research Articles

SGXTuner: Performance Enhancement of Intel SGX Applications Via Stochastic Optimization

Intel <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SGX</i> has started to be widely adopted. Cloud providers (Microsoft Azure, IBM Cloud, Alibaba Cloud) are offering new solutions, implementing <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">data-in-use</i> protection via SGX. A major challenge faced by both academia and industry is providing transparent SGX support to legacy applications. The approach with the highest consensus is linking the target software with SGX-extended <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">libc</i> libraries. Unfortunately, the increased security entails a dramatic performance penalty, which is mainly due to the intrinsic overhead of context switches, and the limited size of protected memory. Performance optimization is non-trivial since it depends on key parameters whose manual tuning is a very long process. We present the architecture of an automated tool, called <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SGXTuner</i> , which is able to find the best setting of SGX-extended <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">libc</i> library parameters, by iteratively adjusting such parameters based on continuous monitoring of performance data. The tool is — to a large extent — algorithm agnostic. We decided to base the current implementation on a particular type of stochastic optimization algorithm, specifically <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Simulated Annealing</i> . A massive experimental campaign was conducted on a relevant case study. Three client-server applications — <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Memcached</i> , <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Redis</i> , and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Apache</i> — were compiled with SCONE's <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sgx-musl</i> and tuned for best performance. Results demonstrate the effectiveness of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SGXTuner</i> .

SMART-technologies in Irrigation Management of a Remote Land Plot

The purpose of this work is to design an automatic irrigation system on a remote land plot. Along with this the objectives of the designed system were the requirement of intelligence and interactivity. In other words the automation system should not only open the solenoid valves according to the schedule, but also control the separate zones taking into account the temperature, soil humidity, weather, etc., while notifying the user of events. The result of this work is the project of an interactive irrigation management system with the possibility of remote interaction. Besides there is a developed client-server application that implements this remote interaction in a simple and familiar way through a mobile application for a smartphone running the Android operating system. It is easy to configure flexibly or to expand the system to suit any needs, to use completely different sensors and actuators, to receive reports on stable operation and planned actions set by algorithms, or on abnormal situations, such as device failure. It is worth noting as an advantage the flexibility and scalability of the developed system in terms of integration with any information management system and digitalization of agriculture.

APLIKASI CLIENT-SERVER UNTUK SISTEM INFORMASI KEPUSTAKAAN PADA PERPUSTAKAAN PEGADILAN NEGERI SIDIKALANG

This study aims to solve the problem of processing book data at the Sidikalang District Court Library, which currently does not have an information system to process library data such as book data, library member data, borrowing and returning books. In the absence of information regarding available books, the library leader, namely customer representative recreation, the Sidikalang District Court does not know exactly the type and number of books available so that it can hamper the development of the library. This problem is resolved by designing a client-server application for library information systems in libraries. Sidikalang District Court. With this library information system it is hoped that it can simplify the work of librarians, the system for recording book data and member data becomes more structured, fast and accurate, accelerates the process of searching for member data, book data, borrowing, and returning transaction data, and services to library members become more good.

Development of Predictions through Machine Learning for Sars-Cov-2 Forecasting in Peru

The SARS-COV-2 virus of the coronavirus family was identified in 2019. This is a type of virus that infects humans and some animals, in Peru it has seriously affected everyone, causing so many deaths, which has resulted in that people be tested to rule out contagion, using laboratory methods recommended by the government of the country. Therefore, the data science methodology was used with this research, where its objective is to predict what types of people are contaminated during SARS-COV-2 by the regions of Peru, identified through laboratory methods, therefore, the ”data bank” was taken by PNDA, the CSV file was used for that study, apart from the fact that it comes from the INS and the CDC of the MINSA. In which, machine learning was developed with the decision tree algorithm and then began coding, in such a way that the distribution called Anaconda was used where it is encoded in Python language, together with that distribution, Jupyter Notebook was used which is a client-server application. The results generated by this research prove that it was possible to identify the types of individuals by SARS-COV-2. These results can help prevention entities against SARS-COV-2 to apply the corresponding preventive measures in a more focused way.

MOBILE ACCESS CONTROL SYSTEM BASED ON RFID TAGS AND FACIAL INFORMATION

Better access control system security comes at a higher price. It many cases the price is too high for small companies, leaving them vulnerable with cheap and insecure systems. In this work we introduce an alternative access control scheme, which improves access control security while lowering the cost. In the proposed model, passive RFID tags are mounted near a turnstile or a smart door. Tag reading and programming is done via NFC chip directly on the users smartphone. To enhance security, together with smartphone-based authorization we require the user to provide his photograph while entering a secure gate. The photograph is then displayed on a monitoring dashboard side-by-side with the registration picture, so that the two can be matched against each other. The developed client-server application offers administrative system used to configure gate access policies and monitor entrances with filters by access time, user and gate. Also, we propose a mobile application that allows gate registration and serves as a door unlock key. The suggested access control model reduces installation costs required, while maintaining good security. The system is fully wireless and uses cheap autonomous RFID-tags as its main component. We hope, that the proposed system architecture will find its application in small to medium-sized companies.

Review of Web Service Technologies: REST over SOAP

Recently, most of the web applications depend on the web services to solve the application integration problem. Web service is an intermediate software that allows the interaction between the applications written by different languages. Web Service is a client-server, modular, self-contained, and dynamic application that ensures the communication between the applications via the World Wide Web (WWW). The aim of this paper is to choice right kind of Web services at design stage of the project. Thus, we provide an overview of web services. Next, we clarify the architecture of web services. After that, we focus on the most popular kinds of web services, the Representational State Transfer (REST) and the Simple Object Access Protocol(SOAP) then explain APIs details. Finally, we address the performance evaluation of the previous works and explained the results as comparison between SOAP and REST. A recommendation to use RESTful web services has been concluded from experimental result.

Performance Analysis of WebRTC and SIP-based Audio and Video Communication Systems

Video and audio communications have become an integral part of all spheres of life. Two commonly used real-time communication protocols for IP-based video and audio communications are the session initiation protocol (SIP) and web real-time communications (WebRTC). These two protocols have been widely used in softphone and video conferencing applications. The main aim of this paper is to make a comparative analysis of the performance of client server applications for video and audio communications developed by both SIP and WebRTC. The SIP system comprises of a desktop client developed in C#, a mobile client developed in Android studio and a FreeSwitch server. For the WebRTC application, the client was developed in JavaScript and the server in Node.js. The WebRTC application also included a speech translation API for real-time speech translation and employed two different codecs namely VP8 and VP9 via a modification of the Session Description Protocol (SDP) header. Results showed that WebRTC peer-to-peer audio communication provides a much lower quality in terms of SSNR than the SIP audio calls. However, for video communications, WebRTC provides better quality in terms of PSNR than SIP. The performance of the WebRTC application was also evaluated with the different codecs in terms of PSNR as well as the impact of the real-time speech translation delay.

PCHET: An efficient programmable cellular automata based hybrid encryption technique for multi-chat client-server applications

This paper demonstrates an efficient programmable Cellular Automata (CA) based hybrid encryption technique (PCHET) for chatting applications involving multiple clients who can chat simultaneously with each other. The proposed scheme is a symmetric key encryption technique, still very lightweight and it is easy to implement. The base of the work lies in the attributes of various CA rules and their cryptographic properties. These principles rely upon the state data of its neighbors and that of its own. Further, it creates chaotic and random next state data which is extremely difficult to anticipate and its inversion is practically exorbitant in all aspects. This work is implemented in java. The evaluation outcomes of different randomness tests prescribed by National Institute of Standards and Technology (NIST) and DIEHARD test suits show that the scheme is capable of generating high degree of randomness in the ciphertext. In addition to these, a thorough comparative investigation is done with existing similar kind of ciphers such as Data Encryption Standard (DES), 3DES and Advanced Encryption Standard (AES). The execution time of the proposed work is much better than the existing scheme as it is practically required for end-to-end encryption in case of chatting applications involving multiple clients. PCHET has achieved an improvement of 1.65% in terms of execution time.

Electronic Lexicography: Traditional and Modern Approaches М. V. Маkarych1), Yu. B. Popova1), M. O. Shved2)

Nowadays there are a lot of modern technologies in electronic lexicography: speech synthesis technology, cross-referencing between dictionary modules, spell-checking functions, etc. The increasing availability of online information has necessitated intensive research in the area of automatic text summarization within the Natural Language Processing community. Belarusian scientists are also interested in this sphere and new lexicographical approaches for creating a linguistic database are shown in the paper. The authors present English-Belarusian-Russian electronic dictionary TechLex. This is the project of the 2nd English Department and the Department of Software for Information Systems and Technologies of the Belarusian National Technical University. The linguistic database of the dictionary is compiled not by the traditional method of processing a large number of paper dictionaries and combining the received translations, but by sequential processing of scientific and technical English-language periodicals. While the designing the dictionary the authors have taken into account the analysis of modern electronic multilingual translation dictionaries and created a client-server application in the Java programming language. The client part of the system contains a mobile application for the Android operating system, which has been tested on tablets and smartphones with different screen diagonals. The interface of the TechLex dictionary is designed taking into account the possibility of adding new subject areas and filling them with appropriate lexical material. The main advantage of our dictionary is that it is the first technical multilingual electronic dictionary having a Belarusian version.

DEVELOPING A CLIENT-SERVER APPLICATION FOR SELECTING AN EMPLOYEE ON THE ANDROID PLATFORM

Android is a relatively new operating system that has become very popular in the mobile device market in a short time. Operating system developers must adhere to the following basic requirements: the new platform must be based on open standards, which will reduce development costs and provide mobile application developers with access to all system functions to create applications. One of the main advantages of the Android platform is its transparency. The Android operating system is open source and free. This allows users to access the source code and understand how application properties and functions are implemented. This article describes the software, structure, functionality, and scope of the client-server application for personnel selection created on the Android platform.

Client-server application framework based on an object-oriented network model

The relationship between the business layer and the underlying data access layers is considered. The disadvantages of the traditional approach based on the relational database and the data access layer (DAO/ORM) are analyzed. A document-oriented database with built above it an object-oriented network model of data presentation is proposed. The integration with the business layer, automatic assembly of business objects using Java reflection without additional specifications, polymorphic storage and transfer of business entities in collections of the document-oriented database is supported.

ThermoBench: A thermal efficiency benchmark for clusters in data centers

The energy efficiency of a data center depends on the cooling cost of clusters in the data center. Enhancing thermal efficiency of clusters is a practical approach to reducing energy consumption cost, optimizing scalability, and improving reliability. In this paper, we propose ThermoBench to evaluate the thermal efficiency of computing and storage clusters deployed in data centers. We shed light on the criteria, metrics and challenges of developing a thermal efficiency benchmark. We pay particular attention to clusters running scalable client-server enterprise applications in data centers. Because these applications are quite popular in modern data centers, thermal efficiency benchmarks for clusters providing services to these applications become critical. We characterize workload conditions in such a cluster computing environment in forms of client sessions of multiple transactional requests. To resemble real-world applications, ThermoBench makes use of the TPC-W benchmark to change transactional requests mix and load over time. We apply ThermoBench to evaluate the thermal efficiency of a real-world cluster. Experimental results show that ThermalBench provides a simple yet powerful benchmark solution for assessing thermal behaviours of computing clusters in data centers as well as offers thermal-aware scheduling strategies during the course of requests dispatching.

Efficient improved ant colony optimisation algorithm for dynamic software rejuvenation in web services

Software rejuvenation is an effective technique to counteract software ageing in continuously-running applications such as web-service-based systems. In a client-server application, where the server is intended to run perpetually, rejuvenation of the server process periodically during the server idle times increases the availability of that service. In these systems, web services are allocated based on the receiver's requirements and server's facilities. Since the selection of a server among candidates while maintaining the optimal quality of service is an NP-hard problem, meta-heuristics seems to be suitable. In this study, the proposed dynamic software rejuvenation as a proactive fault-tolerance technique based on a combination of ant colony optimisation (ACO) and gravitational emulation local search (GELS) so as to determine the optimal times when rejuvenation can be performed and failure rate can be minimised. The newly proposed method combined the public search capabilities of ACO with local search of GELS algorithm in an effort to create a stable algorithm, which can make reaching the global optimum largely possible in the proposed work. The simulation results revealed that the proposed strategy can decrease the failure rate of web services averagely by 28% in comparison with genetic algorithm and decision-tree strategies.

Networking IP Restriction filtering and network address

Permissions setting on a computer is necessary. This is an effort that is not easy to change the system configuration or settings changed by the user. With a network of computers, of course, permissions settings do not need to be done one by one manually. Because in a computer network course there are many collections of computers connected together. Permissions setting so that the system can use the client-server applications that access restrictions can be done effectively. As the implementation of client-server applications can be created using Visual Basic 6.0. This language has been able to access the socket on the Windows operating system, named Winsock API that supports TCP / IP. This protocol is widely used because of the reliability of client-server application programming. The application is divided into two main applications, namely the client and server program name with the name of the Receiver Sender program. Receiver function receives instructions restriction of access rights Sender and sends reports to the Sender process execution. While Sender functions to send instructions restrictions permissions via the Registry to the Receiver. And after the test, the application can block important features available in the Windows operating system. So it is expected that these applications can help in permissions setting on a computer network.

Technological Improvement Rate Estimates for All Technologies: Use of Patent Data and an Extended Domain Description

In this work, we attempt to provide a comprehensive granular account of the pace of technological change. More specifically, we survey estimated yearly performance improvement rates for nearly all definable technologies for the first time. We do this by creating a correspondence of all patents within the US patent system to a set of technology domains. A technology domain is a body of patented inventions achieving the same technological function using the same knowledge and scientific principles. We obtain a set of 1757 domains using an extension of the previously defined classification overlap method (COM). These domains contain 97.14% of all patents within the entire US patent system. From the identified patent sets, we calculated the average centrality of the patents in each domain to estimate their improvement rates, following a methodology tested in prior work. The estimated improvement rates vary from a low of 1.9% per year for the Mechanical Skin treatment- Hair Removal and wrinkles domain to a high of 228.8% per year for the Network management- client-server applications domain. We developed a one-line descriptor identifying the technological function achieved and the underlying knowledge base for the largest 50, fastest 20 as well as slowest 20 of these domains, which cover more than forty percent of the patent system. In general, the rates of improvement were not a strong function of the patent set size and the fastest improving domains are predominantly software-based. We make available an online system that allows for automated searching for domains and improvement rates corresponding to any technology of interest to researchers, strategists and policy formulators.

Software of Rational Choice of Adaptive Technologies for the Cultivation of Grain Crops as an Element of Agriculture Digitalization

Purpose of research. The goal of research is to develop a science-based decision support system for agricultural producers to choose adaptive technologies for growing crops in the European part of Russia.Methods. System approach, database design theory, mathematical modeling, software and information systems development theory, software qualimetry methods.Results. The paper consistently addresses the issues of the need to digitalize agriculture, describes the results of current research on this topic, identifies areas for further research of such developments, and describes the process of creating and testing application software in stages on the example of our own research. As a result of the conducted research, a finished product has been created and tested. It is a computer program that solves not only the problem of increasing the profitability of grain production, but also ensures the environmental orientation of the technologies used, which is extremely important and relevant at the present time. The proposed software package consists of a client-server application for personal computers, a web application, a mobile application for smartphones based on the Android operating system, and two databases (for personal computers and for the online version of the application).Conclusion. There has been created software that allows us to select the technology for cultivating the given grain crop, taking into account the prevailing soil and climatic conditions of a particular territory, and, thus,it can help to increase the profitability of grain production, ensure the environmental orientation of the applied technologies by effectively using mineral fertilizers, fuel and chemical plant protection productsand select the optimal variety or hybrid of grain crops. It can also help to choose agricultural machinery, taking into account the requirements of import substitution and preliminary calculation of the economic efficiency of the proposed agricultural technology.

Development of Software for Computing of Aircraft’s Takeoff and Landing Characteristics Using Expert System Technology

The principles of expert system are proposed in the development of software application for calculations of rational takeoff and landing characteristics. The modular architecture is developed for the process of takeoff and landing parameters calculations in the system. A prototype of a client-server software application for electronic flight bag based on tablet computer was developed on the example of a specific type of Russian aircraft. A post-publication change was made to this article on 21 February 2020 to correct an author name.

СОВРЕМЕННЫЕ ПОДХОДЫ В BACKEND РАЗРАБОТКЕ НА ПРИМЕРЕ ОНЛАЙН-МАГАЗИНА

The article discusses modern approaches and technologies in the development of server applications using the example of an online store. Methods for solving the main tasks encountered in developing the server part of the client-server application using the rest architectural style are presented. The internal structure and logic of the Spring framework and the Liquibase, Hibernate ORM, Lombock libraries are briefly presented.

Electronic Database of Non-Native Speakers’ Speech Errors as a Scientific and Educational Resource (on the Example of Russian Schools)

The article is devoted to the development of an electronic database of speech errors of non-native speakers studying in Russian schools. The database of non-native speakers’ speech errors developed by the authors includes the following parameters: 1) name of the non-native speaker, 2) age, 3) gender, 4) native language, 5) target word / phrase, 6) context1 (context that includes an error), 7) normative spelling, 8) context2 (context with a corrected error), 9) type of text in which the error occurred, 10) category of error, 11) type of error, 12) year of the material collection. Database pattern, as well as database program, which are a client-server Web application, are presented in the article. The study involved 87 non-native speakers of 11 nationalities: Azerbaijanis (25), Uzbeks (13), Ukrainians (13), Kyrghyz (11), Armenians (11), Tajiks (5), Dargins (2), Avars (2), Talysh (2), Belarusians (2), and Vietnamese (1). The authors have collected and systematized educational written texts of 4 types (dictations, essays, summaries, and copyings) of non-native speakers studying in general education schools of the city of Cherepovets of the Vologda Region. At the moment, there are 239 texts, among which: dictations comprise 96, summary - 26, essays - 41, copying - 76. In these texts, 2039 non-normative spellings were found and qualified. The authors of the project introduced a multidimensional system for the classification of errors that were identified in the written texts of the non-native speakers. At the first level, the following types of errors were distinguished: 1) nonspelling, 2) graphic, 3) spelling, 4) lexical, and 5) grammatical. Research and educational problems that can be solved by means of this resource are considered.

Applying modern information technologies during development of client-server mobile application

Рассмотрены современные технологии разработки мобильных приложений на основе клиент-серверной архитектуры. Разработан программный продукт «IRoomDesigner» под операционную систему iOS для дизайна жилых помещений.