How to use the simulator

In order to generate the simulation, press on the Generate Simulation button.

Highlighted Generate Simulation button — The Generate Simulation button location

After waiting a little, you can see the area on the left be populated with the network components. In order to start the visual simulation press the play button, which afterwards can be clicked again to pause. The rewind and fast forward buttons can be clicked to go back and forth between the cycles.

Highlighted simulation control buttons — The simulation control buttons

Pro Tip: keyboard shortcuts exists for the simulation: start/stop can be activated with spacebar, and rewind and fast forward with the left and right keyboard arrows.

Additionally by scrolling down, graphs and stats about the simulation can be seen. Now try changing the parameters of the simulation and see how the visualization and stats changes!

Stats of the simulation — The generated stats from the simulation

Parameter Explanation

Sensor Count: How many sensors will be simulated
Max Cycles: How many cycles will be simulated
Seed: Set to have consistent simulations, otherwise leave blank for full randomness
Request Slots: How many slots for transmitting data are available in a single cycle

The following parameters are available under the Advanced Parameters section:

Data Channels: How many radio channels available for the sensor data transmissions. More data channels means that more sensors can transmit data at the same time on multiple channels, potentially shortening cycle period time
Sensor Measurement Chance: Chance that the sensor, when in idle state, senses a real phenomena and wakes up to send data (ranges from 0.0 to 1.0 meaning 0% to 100%)
Sensor Data Payload Size: Size of the payload, in bytes, that the sensor sends to the gateway. A bigger payload size may lenghten the cycle period time

Stats Explanation

FTR Line Chart

The FTR value represents the current number of sensors that are backed off. A high FTR value means that there is high network congestion and many sensors are currently awaiting their turn. A low FTR value means that a small number of sensor is awaiting their turn and the network is not busy. From the line chart, it can be seen how the FTR evolves as time goes on.

Plot of the FTR value — FTR value for each cycle

As an example the above graph has been generated for a high congested network scenario (50 sensors with 6 slots). The FTR value in the graph ramps up quick, and settles around 19. This means that the FTR equilibrium value is around 19.

Measurement Latency Distribution

The histogram on the right instead represents the distribution of data transmission latencies. The latency in this case is referred as the difference in time between when the data transmission has been received by the gateway and by when the data was first sensed.

As noted by the histogram (generated with the same 50 sensors and 6 slots scenario), most of the messages arrive quick, however there are a few outliers that are caused by the same sensor getting incresedly backed off.