WSN Simulators COOJA Simulator

Описание: In order to realize a real scenario or a test bench which provides realistic results, the physical architecture and the hardware development require
a lot of resources, and the WSN programming and debug become extremely complex.
The WSN simulators can be divided into different categories in relation to their features and applications.
These categories are namely,
i) Code level simulators.
ii) Topology control simulators.
iii) Environment and wireless medium simulators.
Due to the ability to increase the real WSN prototyping, the cross level simulators like COOJA have become an important class of simulators
This kind of simulators operates at three abstraction levels
The network level,
The operating system level, and
The machine code instruction set level.
Although these simulators are open source, flexible, and extensible at all levels,
The test interface, the external connection at a physical level and the direct interaction with the process control via the WSN are very poor.
COOJA simulator is a cross-layer java-based wireless sensor network simulator distributed with Contiki.
It allows the simulation of different levels from physical to application layer, and also allows the emulation of the hardware of a set of sensor nodes.
Contiki is an operating system with a focus on low power IoT devices. 
COOJA is the Contiki network simulator. COOJA allows the large and small networks of Contiki motes to be simulated. 
Contiki offers a java based simulator called as COOJA which is used to simulate the wireless sensors.
COOJA simulator is more flexible so that many parts of the simulator is replaceable and extendable.
The parts of the simulator like simulated node hardware, plug-ins and radio medium can be replaceable.
A simulated Contiki Mote in COOJA is an actual compiled and executing Contiki system.
The system is controlled and analyzed by COOJA.
This is performed by compiling Contiki for the native platform as a shared library, and loading the library into Java using Java Native Interfaces (JNI).