How to Implement Bundling protocols in OMNeT++

To implement the bundling protocol in OMNeT++, we have to group (“BUNDLING”) the data packets together before it transmitted through the network by generating a simulation. This protocol can optimize network efficiency by decreasing overhead, particularly in delay-tolerant networks (DTNs) where the data might be transferred across long distances with sporadic connectivity.

Here, we provide a step-by-step guide on how to implement bundling protocols in OMNeT++:

Step-by-Step Implementation:

1. Set Up OMNeT++ and INET Framework

• Install OMNeT++: Make certain that OMNeT++ is properly installed and configured.
• Install INET Framework: For network communication, routing and data transmission, we need to download and install the INET framework that offers models.

2. Define the Network Topology

Generate a network topology where nodes can communicate with each other. These nodes will execute the bundling protocol, where data is collected, bundled, and transmitted.

Example NED File (BundlingNetwork.ned):

package mynetwork;

import inet.node.inet.StandardHost;

import inet.node.inet.Router;

network BundlingNetwork

{

submodules:

nodeA: StandardHost {

@display(“p=100,200”);

}

nodeB: StandardHost {

@display(“p=300,200”);

}

router: Router {

@display(“p=200,300”);

}

}

In this example:

• nodeA, nodeB: Denotes the nodes that will execute the bundling protocol.
• router: Acts as an intermediary to direct bundled data packets amongst nodes.

3. Create a Custom Bundling Protocol Module

Execute the bundling protocol by generating a new module which includes stating how data are aggregated, grouped and transmitted.

Example: Bundling Protocol (BundlingProtocol.ned)

package mynetwork;

import inet.applications.base.ApplicationBase;

simple BundlingProtocol extends ApplicationBase

{

gates:

input upperLayerIn;

output upperLayerOut;

input lowerLayerIn;

output lowerLayerOut;

}

BundlingProtocol.cc (Basic Implementation)

#include “inet/common/INETDefs.h”

#include “inet/applications/base/ApplicationBase.h”

Define_Module(BundlingProtocol);

void BundlingProtocol::initialize(int stage) {

ApplicationBase::initialize(stage);

if (stage == INITSTAGE_LOCAL) {

bundleSizeThreshold = par(“bundleSizeThreshold”).intValue();

bundleTimeout = par(“bundleTimeout”).doubleValue();

bundle.clear();

scheduleAt(simTime() + bundleTimeout, bundleTimeoutEvent);

}

}

void BundlingProtocol::handleMessageWhenUp(cMessage *msg) {

if (msg == bundleTimeoutEvent) {

sendBundle();

scheduleAt(simTime() + bundleTimeout, bundleTimeoutEvent);

} else {

handleUpperMessage(msg);

}

}

void BundlingProtocol::handleUpperMessage(cMessage *msg) {

bundle.push_back(msg);

if (bundle.size() >= bundleSizeThreshold) {

sendBundle();

}

}

void BundlingProtocol::sendBundle() {

if (!bundle.empty()) {

cPacket *bundlePacket = new cPacket(“Bundle”);

for (auto &msg : bundle) {

bundlePacket->encapsulate(check_and_cast<cPacket *>(msg));

}

sendDown(bundlePacket);

bundle.clear();

}

}

void BundlingProtocol::finish() {

if (!bundle.empty()) {

sendBundle();  // Send any remaining messages

}

}

In this sample:

• bundleSizeThreshold: The maximum number of packets that can be bundled together.
• bundleTimeout: The time after which the bundle is sent, even if it is not full.
• handleUpperMessage(): Accumulates packets and stores them in the bundle.
• sendBundle(): Bundles the collected packets and sends them as a individual packet.

4. Configure the Simulation

In omnetpp.ini file, we need to configure the simulation to use the custom bundling protocol.

Example Configuration in omnetpp.ini:

network = BundlingNetwork

**.nodeA.applications[0].typename = “BundlingProtocol”

**.nodeB.applications[0].typename = “BundlingProtocol”

**.nodeA.applications[0].bundleSizeThreshold = 5

**.nodeA.applications[0].bundleTimeout = 1s

**.nodeB.applications[0].bundleSizeThreshold = 5

**.nodeB.applications[0].bundleTimeout = 1s

5. Simulate and Monitor the Bundling Protocol

Run the simulation and observe the bundling process. You can find metrics like the number of bundles sent, the average size of bundles, and the influence on network performance.

Example Configuration for Monitoring Metrics:

network = BundlingNetwork

**.nodeA.applications[0].numBundlesSent.recordScalar = true

**.nodeA.applications[0].averageBundleSize.recordScalar = true

**.nodeB.applications[0].numBundlesSent.recordScalar = true

**.nodeB.applications[0].averageBundleSize.recordScalar = true

This configuration logs the number of bundles sent and the average size of the bundles, which can help assess the efficiency of the protocol.

6. Analyze and Optimize the Bundling Protocol

After running the simulation, analyze the results to define the efficiency of the bundling strategy. Consider factors like:

• Latency: The delay presented by bundling packets.
• Throughput: The total amount of data transmitted, considering the bundling.
• Efficiency: How well the bundling protocol diminishes overhead and improves network performance.

7. Extend the Bundling Protocol

You can extend the basic bundling protocol with additional features includes:

• Priority-based Bundling: Line up specific packets to be bundled and sent first.
• Adaptive Bundling: Depends on the conditions include congestion or link quality, fine-tune the grouping techniques.
• Error Handling: Execute mechanisms to manage packet loss or errors in the bundling process.

Example: Adaptive Bundling

void BundlingProtocol::handleUpperMessage(cMessage *msg) {

bundle.push_back(msg);

// Adjust bundle size threshold based on network conditions

if (isNetworkCongested()) {

bundleSizeThreshold = std::max(1, bundleSizeThreshold / 2);  // Reduce bundle size

} else {

bundleSizeThreshold = std::min(maxBundleSize, bundleSizeThreshold + 1);  // Increase bundle size

}

if (bundle.size() >= bundleSizeThreshold) {

sendBundle();

}

}

bool BundlingProtocol::isNetworkCongested() {

// Placeholder for actual congestion detection logic

return uniform(0, 1) > 0.7;  // Randomly simulate congestion

}

8. Document and Report Findings

After completing the simulations, document the bundling strategies examined, the results acquired, and any enhancement made. This will help in understanding the trade-offs amongst bundling and network performance.

Through this process, we completely know about the implementation of bundling protocol in the OMNeT++ with the help of the INET framework’s functionalities. For further requirements, we will offer it as per your requests.

For additional simulation results on Bundling protocols using the OMNeT++ tool, feel free to reach out to the omnet-manual.com team, and we will provide you with prompt assistance.