N3Sim is a complete simulation framework for diffusion-based molecular communications, which allows the evaluation of the communication performance of molecular networks with several transmitters and receivers in an infinite space with a given concentration of molecules. Transmitters encode the information by releasing particles into the medium, thus varying the concentration rate in their vicinity. The diffusion of particles through the medium is modeled as Brownian motion, taking into account particle inertia and collisions among particles. Finally, receivers decode the information by sensing the local concentration in their neighborhood.
The user interface layer interacts with the user to read the input data for the simulation, while the data layer writes the simulation results to files. The domain layer contains the "intelligence" of the system, i.e., the molecular communication model. N3Sim is a Java-based simulator; therefore, it can be used in different operating systems with the appropriate Java virtual machine. The simulation parameters are determined by means of a text configuration file editable by the user, which defines the values of all possible variables in the simulation. These are separated into four groups of variables for clarity: simulation, space, transmitters and receivers. In addition, N3Sim allows to automate the execution of multiple simulations in a simple manner by means of user-defined scripts.
Technical requirements and scalability: N3Sim is designed to be executed on a single machine with Java 1.6 or higher. The scalability of the simulator can be improved by selecting a higher simulation time step (at the expense of the accuracy) or by deactivating the collisions among molecules in scenarios with a low molecular concentration. The time granularity of a simulation is defined by the user by choosing the simulation time step in the configuration file (typically a few ms). The simulation space can be either bounded or unbounded, and both 2-dimensional and 3-dimensional configurations are supported
See also:
I. Llatser, I. Pascual, N. Garralda, A. Cabellos-Aparicio, M. Pierobon, E. Alarcón and J. Solé-Pareta, “Exploring the Physical Channel of Diffusion-based Molecular Communication by Simulation”, in Proc. of IEEE GLOBECOM, Houston (USA), December 2011.
