How to Start Unicast Routing Projects Using OMNeT++

To start a Unicast Routing project using OMNeT++ which comprises of replicating a network in which packets are transmitted from one certain source to one particular destination that is unicast interaction. The routing protocol will need to determine the paths to make sure that packets attain the exact destination according to the network topology. General routing protocols are frequently designed for unicast routing with Distance Vector and Link-State Routing.

Let’s we see how to implement and simulate the Unicast Routing project using OMNeT++:

Steps to Start Unicast Routing Projects in OMNeT++

Step 1: Install OMNeT++ and INET Framework

  1. Download OMNeT++:
    • We should download and install the new version of OMNeT++ on the system.
  2. Verify Installation:
    • When OMNeT++ installed then we will need to make and execute an example project to confirm that OMNeT++ is properly configured.
  3. Install INET Framework:
    • INET framework is a robust framework for OMNeT++, which supports models for network protocols and devices with routing protocols for unicast and multicast. We can download and install INET through GitHub.
    • We can be installed INET either via OMNeT++’s module manager or by copying the GitHub repository.

Step 2: Set Up a New OMNeT++ Project

  1. Create a New OMNeT++ Project:
    • Go to OMNeT++ IDE by navigating File > New > OMNeT++ Project.
    • Select “Simple Project” and name it to the project as UnicastRouting.
  2. Create Network Topology:
    • Make the network topology using a .ned file. We will contain minimum two nodes such as source and destination including intermediate routers (if applicable) for unicast routing.

Example of a simple network with two hosts and a router:

network UnicastRoutingNetwork {

submodules:

router1: Router;

host1: Host;

host2: Host;

connections:

host1.ethg++ <–> EthernetInterface <–> router1.ethg++;

router1.ethg++ <–> EthernetInterface <–> host2.ethg++;

}

In this case:

  • router1 is an intermediate router.
  • host1 is the source node.
  • host2 is the destination node.

Step 3: Implement the Unicast Routing Logic

The main target is to route packets from a source host to a certain destination in unicast routing. We can execute this logic to utilise diverse routing algorithms such as Distance Vector or Link-State.

Example using Distance Vector or Link-State Routing:

  1. Router Module:
    • The router sends packets to the destination. It executes the routing depends on a pre-computed routing table (distance vector or link-state) or utilises an on-demand routing protocol.
  2. Routing Table:
    • Every single router sustains a routing table, which defines the next hop for packets attaining every destination.
  3. Packet Forwarding:
    • Once a packet is obtained then the router verifies their routing table and sends the packet to the destination.

Example of a simple Router Module, which utilises a static routing table:

class Router : public cSimpleModule {

private:

std::map<int, int> routingTable;  // Destination -> Next hop

protected:

virtual void initialize() override {

// Initialize the routing table

routingTable[2] = 1;  // For example: router1 sends packets to router2 for destination 2

}

virtual void handleMessage(cMessage *msg) override {

if (msg->isSelfMessage()) {

// Handle self messages (if any)

} else {

// Handle incoming packets

cPacket *pkt = check_and_cast<cPacket*>(msg);

int destination = pkt->getDestination()

// Find next hop using the routing table

if (routingTable.find(destination) != routingTable.end()) {

// Forward the packet to the next hop

send(pkt, “out”, routingTable[destination]);

} else {

// If no route found, drop or send an error

delete pkt;

}

}

}

};

In this example:

  • The router contains a static routing table that connects a destination to a next hop.
  • Incoming packets are sent according to the routing table.

Step 4: Define a Custom Packet Format (if needed)

If we are utilising custom packets for unicast routing then we deliberate a custom packet class, which has fields as the destination address.

Example:

class UnicastPacket : public cPacket {

public:

int destination;

UnicastPacket(const char *name = nullptr) : cPacket(name) {}

virtual void parsimPack(cCommBuffer *buffer) override {

cPacket::parsimPack(buffer);

doPacking(buffer, destination);

}

virtual void parsimUnpack(cCommBuffer *buffer) override {

cPacket::parsimUnpack(buffer);

doUnpacking(buffer, destination);

}

};

This UnicastPacket class prolongs cPacket and integrates a destination field to specify the destination of packet.

Step 5: Configure the Simulation in omnetpp.ini

We can set simulation metrics with routing protocols, traffic generation, and network topology using omnetpp.ini file. We will want to indicate host sets up, router settings, and application-level settings for unicast routing.

Example omnetpp.ini configuration:

network = UnicastRoutingNetwork

sim-time-limit = 100s

[Config Default]

*.router1.routingProtocol = “Static”

*.router1.routingTable = “1->2”

*.host1.app[0].typename = “UdpBasicApp”

*.host1.app[0].destAddr = “host2”

*.host1.app[0].startTime = 1s

*.host1.app[0].messageLength = 1000B

*.host1.app[0].numMessages = 100

In this set up:

  • The routing protocol for router1 is configured to “Static” that means it contains a pre-configured routing table.
  • Host1 makes UDP traffic to the Host2.

Step 6: Implement Traffic Generation (Optional)

One or more hosts make traffic, which is transmitted to the destination in a normal unicast routing simulation. We can be utilised the UdpBasicApp from INET to make UDP traffic.

Example for Host1:

*.host1.app[0].typename = “UdpBasicApp”

*.host1.app[0].destAddr = “host2”

*.host1.app[0].startTime = 1s

*.host1.app[0].messageLength = 1000B

*.host1.app[0].numMessages = 100

This set up makes an application at Host1 which transmits the 100 UDP messages to Host2 beginning at 1 second, each message take place 1000 bytes long.

Step 7: Run and Observe the Simulation

  1. Compile and Run:
    • In OMNeT++ IDE, we will need to compile the project and then execute the simulation.
    • Make use of Tkenv (OMNeT++’s graphical interface) to envision the network, the packet flows, and the routing decisions.
  2. Debugging and Logging:
    • In C++ code, integrate the logging to utilise EV macros monitoring how packets are sent and the routing tables are modernised.
    • Monitor the flow of packets and make sure that they are properly routed from the source to the destination.

Example logging within the Router module:

EV << “Received packet with destination ” << pkt->getDestination() << endl;

  1. Performance Metrics:
    • We have to estimate the performance parameters like packet delivery time, hops, and overhead.

Step 8: Extend and Optimize

  1. Multiple Routers:
    • Integrate additional routers to the network and prolong the routing logic to offer more complex scenarios.
  2. Dynamic Routing:
    • We can be prolonged this project containing dynamic routing protocols such as OSPF or RIP, according to the network modifications which permit routers modifying its routes.
  3. Failures and Recovery:
    • Mimic failures like a router or link to drop, and also measure how the network adjusts or retrieves.
  4. Traffic Patterns:
    • Test with various traffic patterns with ding bursty or constant traffic and to experiment how the routing algorithm manages diverse network loads.

Conclusion

To make a Unicast Routing project that has requires replicating a network in which packets are forwarded from a certain source to a particular destination depends on the pre-configured or actively computed routing table in OMNeT++. To utilise INET, we can be replicated some routing protocols like Distance Vector or Link-State Routing. In OMNeT++, executing the routers including routing tables and creating network topologies, we can be examined unicast routing behavior in various kinds of network sets up and conditions.

We had gathered the simulation approach and more insights that support you to replicate and analyse the Unicast Routing Projects within OMNeT++ environment. If needed, we will deliver the detailed structured for entire execution process in another manual.

To start your Unicast Routing project using OMNeT++ we at phdprojects.org are ready to help you out with customised results , drop us a mail to get expert guidance.