Simplicity, reproducibility and scalability for huge wireless sensor network simulations.

Programa de P?s-Gradua??o em Ci?ncia da Computa??o. Departamento de Ci?ncia da Computa??o, Instituto de Ci?ncias Exatas e Biol?gicas, Universidade Federal de Ouro Preto.Neste trabalho apresentamos duas contribui??es para a literatura de redes de sensores sem fio (WSN). A primeira ? um modelo geral para alcan?ar a reprodutibilidade no n?vel do kernel em simuladores paralelos. Infelizmente, os usu?rios devem implementar do zero como suas simula??es se repetem em simuladores WSN, mas uma simula??o paralela ou distribu?da imp?e o princ?pio de concorr?ncia, n?o trivial de ser implementada por n?o especialistas. Testes usando o simulador chamado JSensor comprovaram que o modelo garante o n?vel mais restrito de reprodutibilidade, mesmo quando as simula??es adotam diferentes n?meros de threads ou diferentes m?quinas em m?ltiplas execu??es. A segunda contribui??o ? o simulador JSensor, um simulador paralelo de uso geral para aplica??es WSN de grande escala e algoritmos distribu?dos de alto n?vel. O JSensor introduz elementos de simula??o mais realistas, como o ambiente representado por c?lulas personaliz?veis e eventos de aplica??o que representam fen?menos naturais, como raios, vento, sol, chuva e muito mais. As c?lulas s?o colocadas em uma grade que representa o ambiente com caracter?sticas do espa?o definido pelos usu?rios, como temperatura, press?o e qualidade do ar. Avalia??es experimentais mostram que o JSensor tem boa escalabilidade em arquiteturas de computadores multi-core, alcan?ando um speedup de 7,45 em uma m?quina com 16 n?cleos com tecnologia Hyper-Threading, portanto 50% dos n?cleos s?o virtuais. O JSensor tamb?m provou ser 21% mais r?pido que o OMNeT++ ao simular um modelo do tipo flooding.In this work we present two contributions for the wireless sensor network (WSN) literature. The first one is a general model to achieve reproducibility in kernel level of parallel simulators. Unfortunately, users must implement how their simulations repeat from scratch in WSN simulators, but a parallel or distributed simulation imposes the concurrence principle, not trivial to be implemented by non-specialists. Tests using the simulator named JSensor proved that the model guarantees the most restrict level of reproducibility, even when simulations adopt different number of threads or different machines in multiple runs. The second contribution is the JSensor simulator, a parallel general purpose simulator for large scale WSN applications and high-level distributed algorithms. JSensor introduces more realistic simulation elements, such as the environment represented by customizable cells and application-events representing natural phenomena, such as lightning, wind, sun, rain and more. The cells are placed in a grid that represents the environment with characteristics of the space defined by the users, such as temperature, pressure and air quality. Experimental evaluations show that JSensor has good scalability in multi-core computer architectures, achieving a speedup of 7.45 in a machine with 16 cores with Hyper-Threading Technology, thus 50% of cores are virtual ones. JSensor also proved to be 21% faster than OMNeT++ while simulating a flooding model

JSensor : a parallel simulator for huge wireless sensor networks applications.

This paper presents JSensor, a parallel general purpose simulator which enables huge simulations of Wireless Sensor Networks applications. Its main advantages are: i) to have a simple API with few classes to be extended, allowing easy prototyping and validation of WSNs applications and protocols; ii) to enable transparent and reproducible simulations, regardless of the number of threads of the parallel kernel; and iii) to scale over multi-core computer architectures, allowing simulations of more realistic applications. JSensor is a parallel event-driven simulator which executes according to event timers. The simulation elements, nodes, application, and events, can send messages, process task or move around the simulated environment. The mentioned environment follows a grid structure of extensible spatial cells. The results demonstrated that JSensor scales well, precisely it achieved a speedup of 7.45 with 16 threads in a machine with 16 cores (eight physical and eight virtual cores), and comparative evaluations versus OMNeT++ showed that the presented solution could be 43 times faster