To simulate a Grid Topology using OMNeT++, which comprises making a network in which nodes are arranged in a grid structure, with each node connected to its nearby neighbours (north, south, east, and west). This kind of topology is helpful for wireless sensor networks, mesh networks, or any structured network in which regular node placement is needed. We will guide you to simulating a Grid Topology in OMNeT++ using the INET framework:
Steps to Simulate Grid Topology in OMNeT++
- Install OMNeT++ and INET Framework:
Make certain we have OMNeT++ and the INET framework installed and set up appropriately, as they offer the essential modules and tools for networking simulations.
- We download and install OMNeT++.
- Download and install the INET Framework.
- Define the Grid Topology in NED File:
A grid topology include nodes arranged in a 2D grid in which each node is connected to its neighbouring nodes. Here is an instance NED file that describes a simple grid topology:
network GridTopologyNetwork
{
parameters:
int gridSizeX = default(3); // Number of nodes in X direction (columns)
int gridSizeY = default(3); // Number of nodes in Y direction (rows)
submodules:
// Define the nodes in the grid
node[gridSizeX][gridSizeY]: <NodeType> {
@display(“p=100+150*x,100+150*y”); // Distribute nodes in a grid pattern
}
connections allowunconnected:
// Connect each node to its right neighbor
for x=0..gridSizeX-2, y=0..gridSizeY-1 {
node[x][y].ethg++ <–> Eth100M <–> node[x+1][y].ethg++;
}
// Connect each node to its bottom neighbor
for x=0..gridSizeX-1, y=0..gridSizeY-2 {
node[x][y].ethg++ <–> Eth100M <–> node[x][y+1].ethg++;
}
}
In this example:
- gridSizeX and gridSizeY identify the dimensions of the grid.
- node[gridSizeX][gridSizeY] makes the grid of nodes, each placed at regular intervals.
- ethg++ denotes Ethernet gates used to connect nodes.
- Eth100M is a 100 Mbps Ethernet link, which connects nodes to their neighbours.
- Define Node Types in NED:
We can utilize the INET framework’s StandardHost for nodes or make own node types. Each node will perform as a part of the grid and can perform communication tasks such as forwarding packets.
Example of a simple node type:
import inet.node.inet.StandardHost;
module NodeType extends StandardHost
{
parameters:
@display(“i=device/laptop”); // Use a laptop icon to represent each node
}
This describes each node as a StandardHost (from the INET framework), capable of simple networking functionalities like routing, TCP, UDP, and so on.
- Configure the INI File:
The omnetpp.ini file is used to define simulation parameters, such as the number of nodes, traffic patterns, routing protocols, and simulation duration.
Here’s an example INI file configuration for simulating traffic across the grid:
[General]
network = GridTopologyNetwork
sim-time-limit = 50s # Simulation time
# Set the grid size (number of rows and columns)
*.gridSizeX = 3
*.gridSizeY = 3
# Configure IP addresses for the nodes in the grid
*.node[*][*].networkLayer.ipv4.address = “10.0.x.y”
# Configuring traffic (TCP) from the top-left node to the bottom-right node
*.node[0][0].numApps = 1
*.node[2][2].numApps = 1
# Define a TCP client on the top-left node and a TCP server on the bottom-right node
*.node[0][0].app[0].typename = “TcpBasicClientApp”
*.node[0][0].app[0].connectAddress = “10.0.2.2” # IP of bottom-right node
*.node[0][0].app[0].startTime = 2s
*.node[0][0].app[0].stopTime = 48s
*.node[2][2].app[0].typename = “TcpBasicServerApp” # TCP server on the bottom-right node
In this configuration:
- Grid size is set to 3×3.
- Each node gets an IP address according to its position in the grid.
- Node[0][0] (top-left) performs as a TCP client sending data to Node[2][2] (bottom-right) that performs as a TCP server.
- Traffic Generation Using TCP or UDP:
We can replicate traffic using either TCP or UDP. The following is an example of how to configure UDP traffic:
# Configuring UDP traffic from Node[0][0] to Node[2][2]
*.node[0][0].app[0].typename = “UdpBasicApp”
*.node[0][0].app[0].destAddresses = “10.0.2.2” # Destination IP (bottom-right node)
*.node[0][0].app[0].destPort = 5000
*.node[0][0].app[0].packetLength = 1024B
*.node[0][0].app[0].sendInterval = uniform(1s, 2s)
*.node[0][0].app[0].startTime = 2s
*.node[0][0].app[0].stopTime = 48s
# Configure the bottom-right node as a UDP sink
*.node[2][2].app[0].typename = “UdpSink”
*.node[2][2].app[0].localPort = 5000
This makes UDP traffic from Node[0][0] to Node[2][2], with a randomly distributed interval among the packet transmissions.
- Run the Simulation:
- We can open OMNeT++ IDE, compile the project, and run the simulation.
- Utilize Qtenv to envision the grid topology and observe how packets are sent across the grid.
In the course of the simulation, we can monitor packet transmission across several nodes as the data is routed from the top-left node to the bottom-right node.
- Analyze the Results:
The simulation environment OMNeT++ offers detailed logs and statistical information, which we can investigate. We can observe:
- Throughput: The data rate among the nodes.
- Latency: The delay as packets are forwarded across several nodes.
- Packet Loss: If any packets are dropped during transmission.
We can be used Scave or Plove to generate plots of the simulation outcomes and investigate parameters such as latency and throughput.
- Advanced Features (Optional):
- Routing Protocols: We can be inserted a routing protocol such as OLSR, AODV, or custom routing to replicate how packets are routed across the grid.
- Mobility Models: Apply mobility models to nodes if the grid is part of a mobile ad-hoc network (MANET).
- Energy Models: Mimic energy consumption for each node to model wireless sensor networks in which energy efficiency is crucial.
- Error Models: Launch link errors or packet loss to mimic real-world network conditions.
Example for Applying a Routing Protocol (e.g., OLSR):
# Enable OLSR routing on all nodes
*.node[*][*].hasNetworkLayer = true
*.node[*][*].ipv4.routingProtocol = “Olsr”
*.node[*][*].olsr.interfaceTableModule = “^.interfaceTable”
*.node[*][*].olsr.routingTableModule = “^.routingTable”
This configuration allows the OLSR routing protocol, permitting nodes to dynamically route packets over the grid.
Summary:
- Topology Definition: We can use NED to make a grid topology with nodes are connected to their neighbours.
- Node Configuration: Utilize INET’s StandardHost or custom node types to denote the nodes in the grid.
- Traffic Simulation: Replicate traffic using TCP or UDP applications among the nodes.
- Run and Analyze: We can run the simulation in OMNeT++, and utilize built-in tools to investigate performance parameters such as throughput, latency, and packet loss.
These fundamental method, supported by sample snippets for Grid Topology projects, was simulated and analysed in OMNeT++ using the INET framework. Similarly, we will also be offered essential data on this topic.
To simulate grid topology projects utilizing the OMNeT++ tool, we at phdprime.com are fully equipped to ensure the successful completion of your work within the specified timeframe. For optimal service, please send to phdprime.com your details via email, and we will deliver the highest quality simulation services.
