Solução eficiente para balanceamento de carga em servidores de aplicação java / Efficient load balancing solution for java application servers

Atualmente, o desenvolvimento de aplicações para internet é a melhor forma de oferecer facilidade de acesso aos usuários a partir de um computador ou de um dispositivo móvel, pois não é necessário instalar nenhum software adicional. Dentre as diversas soluções para o desenvolvimento de aplicações, a plataforma Java tem se tornado a procurada por ser independente de ambiente computacional, oferecendo uma variedade de bibliotecas, e projetada para executar código com segurança. Assim, aplicações baseadas em Java passaram a automatizar atividades operacionais das áreas administrativa e acadêmica das universidades federais. Em certas ocasiões, estas aplicações podem sofrer uma grande demanda de requisições simultâneas provocando baixos tempos de resposta ou até a interrupção dos serviços. Uma solução para atender a grande demanda de requisições simultâneas é utilizar várias máquinas na rede atuando como um único servidor, através de um balanceamento de carga. Este trabalho apresenta um estudo comparativo entre os balanceadores de carga Apache Server com Tomcat Connector mod_jk e o HAProxy dos servidores de aplicação Java que hospedam os Sistemas Institucionais Integrados de Gestão (SIG/UFRN) da Universidade Federal de Itajubá.

A Dynamic Privacy Protection Mechanism for Spatiotemporal Crowdsourcing

In spatiotemporal crowdsourcing applications, sensing data uploaded by participants usually contain spatiotemporal sensitive data. If application servers publish the unprocessed sensing data directly, it is easy to expose the privacy of participants. In addition, application servers usually adopt the static publishing mechanism, which is easy to produce problems such as poor timeliness and large information loss for spatiotemporal crowdsourcing applications. Therefore, this paper proposes a spatiotemporal privacy protection (STPP) method based on dynamic clustering methods to solve the privacy protection problem for crowd participants in spatiotemporal crowdsourcing systems. Firstly, the working principles of a dynamic privacy protection mechanism are introduced. Then, based on k-anonymity and l-diversity, the spatiotemporal sensitive data are anonymized. In addition, this paper designs the dynamic k-anonymity algorithm based on the previous anonymous results. Through extensive performance evaluation on real-world data, compared with existing methods, the proposed STPP algorithm could effectively solve the problem of poor timeliness and improve the privacy protection level while reducing the information loss of sensing data.

Database Connection Technologies from JSP Pages and Java Web Application Servlets

The purpose of the study is to demonstrate the diversity of solutions on the issue of connecting to a database, including a description of the developed connection controller class, as well as various ways to create connection pools on a web server and application servers. The article discusses the practical issues of using JDBC technology when building a Java web application. In the examples, the presentation and business layer of the application are developed using JSP-pages and servlets, the database operates on the MySQL platform. The described methods for creating and configuring a connection pool are shown on the example of the ApacheTomcat web server and the GlassFish application server. The question of optimizing database connections in Java applications remains open, despite the diversity of solutions. The study examines and proposes methods for constructing classes of connectors, various methods for creating pool connections, and describes the results of solving problems arising from the implementation of the described techniques. A detailed classification of ways to connect to the database is given.

ANÁLISIS DE ATAQUES RANSOMWARE EN SERVIDORES WEB, LINUX Y WINDOWS

El presente trabajo realiza un análisis de revisión bibliográfica de ataques ransomware en Servidores Web basados en Sistemas Operativos Linux y Windows. Por ello se realizó un análisis comparativo de vulnerabilidad de los Servidores de aplicaciones JBoss, Apache y estructura de base de datos Redis. Los resultados evidencian que los ataques con mayor frecuencia están dirigidos a los Hospitales teniendo en cuenta que los cibercriminales suelen pedir entre $200 y $500 dólares para restaurar los archivos, para el caso del ransomware Samsam para Windows, el atacante interviene la red de la organización vía SSH se autentica al Servidor JBoos. A partir del estudio realizado se puede concluir con una matriz de análisis, de ataques ransomware de varias familias CTB-loker, SamSam, CryptoWall 4.0, Linux.Enconder y FairWare y un listado de herramientas de alerta temprana contra ataques ransomware visto que cifran los directorios de los Sitios Web, por ende permite plantear trabajos futuros de nuevos tipos de ransomware por medio de herramientas de simulación.PALABRAS CLAVE: Ransomware; Servidor Web; Linux; Windows.ANALYSIS OF RANSOMWARE ATTACKS ON WEB SERVERS, LINUX AND WINDOWSABSTRACTThe present work performs an analysis of bibliographic review of ransomware attacks in Web Servers based on Linux and Windows Operating Systems. Therefore, a comparative vulnerability analysis of the JBoss Application Servers, Apache and Redis database structure was carried out. The results show that the most frequent attacks are directed to Hospitals taking into account that cybercriminals usually request between $ 200 and $ 500 dollars to restore the files, for the Samsam for Windows ransomware case, the attacker intervenes the organization's network via SSH authenticates to the JBoos Server. From the study carried out it can be concluded with a matrix of analysis, ransomware attacks of several families CTB-loker, SamSam, CryptoWall 4.0, Linux. Enconder and FairWare and a list of tools for early warning against ransomware attacks seen that encrypt the directories of the Websites, therefore allows to propose future works of new types of ransomware by means of simulation tools.KEYWORDS: Ransomware; Web Server; Linux; Windows.

EVALUATION OF SERVICES QUALITY IN IMS

The main stages of the historical development of telecommunication networks are shown. It is noted that today the most common concepts are NGN (Next Generation Network), supporting the functionality of Triple-Play Services (triple services – voice, video and data transmission), as well as IMS (IP Multimedia Subsystem), which combines cellular technology and landline communications. They are able to provide a wide range of services: basic, additional, intelligent. In addition, IMS is able to provide mobile services. The IMS architecture layers are presented – transport layer, control layer; layer of service and application servers. Particular attention is paid to the layer of service and application servers. Based on the analysis of ITU recommendations, the main telecommunication services quality indexes are determined, namely, the time of service provision, the length of the queue that the service request falls into to wait for service on the server, and the probability of refusing to provide services. Based on the proposed mathematical models of the NGN intelligent superstructure, analytical expressions are presented for calculating the quality indexes of intelligent services in NGN for one type of service and for K types of services, taking into account the self-similarity of traffic, and without taking into account. To evaluate the quality of services in IMS, it is proposed to use the approaches of queuing theory and tensor analysis. Tensor analysis offers a mathematical apparatus for transforming coordinate systems, considering IMS as a set of geometric objects whose projections are different in different coordinate systems, but the physical properties of the objects themselves do not change. Expressions are proposed that make it possible to calculate the following QoS indexes in IMS: average queue length, average residence time of an application in the system for all types of services in IMS. It is considered that the incoming traffic is the simplest. Further development of the work is to take into account the self-similar nature of traffic, which is created by the flow of requests for services that come to IMS, as well as the limitations of the server buffer, which will allow a more accurate assessment of the quality of services in IMS.