Applicable Versions | NetSim Standard | NetSim Pro |

Applicable Releases | v12 | v13 |

In NetSim's implementation of the Routing Protocol for Low-Power and Lossy Networks (RPL), compliance is maintained with RFC 6550. This standard specifies that "Rank" serves as a scalar indicator of a node's position or extent within a Destination-Oriented Directed Acyclic Graph (DODAG) version. Furthermore, RFC 6550 delegates the determination of Rank to the Objective Function, which is responsible for computing it based on specific criteria.

The Objective Function within NetSim's RPL framework aims to identify paths characterized by superior link quality. The factors influencing link quality and the radio range of a node in NetSim include:

- Transmitter Power: An increase in transmitter power typically enhances the radio range, allowing signals to be transmitted over greater distances.
- Path Loss: The path loss exponent directly affects the radio range; a higher exponent means more signal attenuation over distance, thereby reducing the range.
- Receiver Sensitivity: Receiver sensitivity, expressed in negative decibels (dB), impacts the range as well. A lower (more negative) receiver sensitivity value suggests a device's capability to detect weaker signals, thus potentially increasing the effective range.
- Spatial separation between nodes: As the distance between nodes increases, path loss increases, reducing the signal strength accordingly.

**Length of the grid environment**: 1000 x 1000 meters**Wireless Channel Characteristics (Adhoc Link Properties)**: Path Loss Only (Log Distance with Path loss exponent=2).**ZigBee Node's Transmitter Power**: 1 mW**Receiver Sensitivity**: -85 dBm

**Length of the grid environment**: 1000 x 100 meters**Wireless Channel Characteristics (Adhoc Link Properties)**: No Path Loss**ZigBee Node's Transmitter Power**: 1 mW**Receiver Sensitivity**: -85 dBm

__Since there is no path loss configured, the signal strength does not get attenuated with distance__. Hence, all nodes are assigned a similar rank value of 2 and become children of the root node.

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