How to Start Logical Topology Project using OMNeT++
To stimulate a Logical Topology project in OMNeT++ has contains the process and replicate a network topology in which the logical connections can be various from the physical connections for instance virtual links in optical networks or overlay networks in P2P systems. Here’s a step-by-step guide:
Steps to Start Logical Topology Project using OMNeT++
- Set up OMNeT++
 
- Install OMNeT++: Download and install the New version of OMNeT++ from the official site.
 - Framework Selection:
- Use INET Framework for basic networking functionalities.
 - Consider the OverSim for overlay networks or logical topologies in P2P systems.
 
 
- Understand Logical Topology Requirements
 
Logical topology suggest on how the data flows in the network, regardless of physical connections. samples are include they are:
- Virtual Circuits are optical networks.
 - Overlay Networks in P2P or content delivery systems act as overlay network.
 - Traffic Engineering in software-defined networks (SDNs) in a congestion.
 
Key considerations:
- The Logical connections are not directly map to the physical links.
 - Logical connection can be classifying the abstract relationships for instance bandwidth, latency.
 
- Define the Logical Topology
 
- Signify the nodes for a logical topology for sample routers, switches, servers.
 - Explain the logical connections among nodes terms on the communication design.
 
- Create Network Topology in NED
 
Logical connections can be defined in the NED (Network Description Language) file.
Example: Basic Logical Topology
network LogicalTopology
{
submodules:
nodeA: Node {
@display(“p=100,100”);
}
nodeB: Node {
@display(“p=300,100”);
}
nodeC: Node {
@display(“p=200,300”);
}
connections allowunconnected:
nodeA.out++ –> nodeB.in++; // Logical link
nodeB.out++ –> nodeC.in++; // Logical link
nodeC.out++ –> nodeA.in++; // Logical link
}
- Configure Logical Connections
 
Explain the parameters of logical connections in the omnetpp.ini file:
- Bandwidth.
 - Delay.
 - Logical link behavior.
 
Example:
[General]
network = LogicalTopology
sim-time-limit = 100s
**.nodeA.out++ –> **.nodeB.in++.datarate = 1Gbps
**.nodeB.out++ –> **.nodeC.in++.datarate = 500Mbps
**.nodeC.out++ –> **.nodeA.in++.delay = 10ms
- Model Logical Topology Behaviors
 
Logical topology projects often involve custom behaviors:
- Routing and Switching:
- Apply modify routing techniques for logical connections.
 - Replicate the virtual circuit settings.
 
 - Traffic Engineering:
- Enhance the congestion distribution with logical connection.
 
 - Failure Simulation:
- Replicate the logical connection or node failures and reroute traffic dynamically.
 
 
Write these behaviors in C++ modules:
void Node::handleLogicalMessage(cMessage *msg) {
// Process message for logical routing
int nextHop = findNextHop(msg);
send(msg, “out”, nextHop);
}
- Simulate Logical Topology in OMNeT++
 
Process for the replication in the OMNeT++ IDE:
- Monitor on the packet flow with logical links.
 - Use animations to envision for the logical connections.
 - Debug using the logs and communication inspection.
 
- Analyze Results
 
- Gather and examine the parameter metrics like as:
- Packet delivery ratio.
 - Utilize the logical connection.
 - Latency and throughput.
 
 - Use OMNeT++’s built-in tools or external tools such as Python or MATLAB for post-simulation study.
 
- Extend the Project
 
Depending on the experiment concentrate, expand the replication with:
- Adding Logical Layers:
- Replicate the multi-layer networks for sample logical on top of physical.
 
 - Implementing Protocols:
- Improve the protocols for logical connection management such as SDN-based control.
 
 - Scalability:
- Add the size and complexity for the logical topology.
 
 
Example Use Cases
- Overlay Networks: Logical connections are content distribution for the overlay of networks.
 - Optical Networks: Logical circuits over the wavelength-division multiplexing (WDM) in a optical networks.
 - SDN Traffic Management: Logical links are described through SDN controllers.
 
Tips
- Start Small: Start by a simple logical topology and increase the improve features.
 - Modular Design: Keep the pattern modular we assign the simple debugging and scalability.
 - Leverage Frameworks: Use the previous frameworks such as INET or OverSim for advanced features.
 
This approach ensures a well-structured simulation of logical topologies in OMNeT++.
From the demonstration we completely aggregate the information about the installation process and simulation procedure for Logical Topology projects that were deploy in the tool of OMNeT++. Additional information regarding the Logical Topology projects will also be provided.