How to Implement ad hoc protocols in OMNeT++
To implement the ad hoc routing protocols in OMNeT++, we can divide them into few steps like setting up the environment, understanding the specific ad hoc protocol you wish to implement, creating the protocol module, integrating it with the INET framework, and testing it. Here, we offer the step-by-step implementation of ad hoc protocols in OMNeT++:
Step-by-Step Implementation:
Step 1: Set Up OMNeT++ and INET Framework
- Install OMNeT++: Make certain that you have installed the latest version of OMNeT++.
- Install INET Framework: Install the INET framework from the INET repository.
Step 2: Understand AODV Protocol
In mobile ad hoc networks (MANETs), we can use the AODV which is a reactive routing protocol. Key concepts like:
- Route Requests (RREQs): Broadcast to discover routes.
- Route Replies (RREPs): Sent in response to RREQs.
- Route Errors (RERRs): Indicate link breakages.
- Hello Messages: Detect the link status sends to the neighbors by optional messages.
Step 3: Create the AODV Protocol Module
Define the Module in .ned File
Construct a .ned file for the AODV protocol module.
simple AODV
{
parameters:
double helloInterval @unit(s) = default(1s);
double rreqRetryTimeout @unit(s) = default(2s);
gates:
input fromNetworkLayer;
output toNetworkLayer;
input fromMacLayer;
output toMacLayer;
}
Implement the Module in C++
Create the corresponding .cc and .h files.
AODV.h
#ifndef __AODV_H_
#define __AODV_H_
#include <omnetpp.h>
#include “inet/networklayer/contract/IRoutingTable.h”
#include “inet/networklayer/common/L3AddressResolver.h”
#include “inet/networklayer/ipv4/IPv4Datagram.h”
using namespace omnetpp;
using namespace inet;
class AODV : public cSimpleModule
{
private:
double helloInterval;
double rreqRetryTimeout;
IRoutingTable *routingTable;
cMessage *helloMsg;
cMessage *rreqRetryMsg;
protected:
virtual void initialize() override;
virtual void handleMessage(cMessage *msg) override;
void sendHello();
void processHello(cMessage *msg);
void sendRREQ();
void processRREQ(cMessage *msg);
void sendRREP();
void processRREP(cMessage *msg);
void processRERR(cMessage *msg);
public:
AODV();
virtual ~AODV();
};
#endif
AODV.cc
#include “AODV.h”
Define_Module(AODV);
AODV::AODV()
{
helloMsg = nullptr;
rreqRetryMsg = nullptr;
}
AODV::~AODV()
{
cancelAndDelete(helloMsg);
cancelAndDelete(rreqRetryMsg);
}
void AODV::initialize()
{
helloInterval = par(“helloInterval”);
rreqRetryTimeout = par(“rreqRetryTimeout”);
routingTable = getModuleFromPar<IRoutingTable>(par(“routingTableModule”), this);
helloMsg = new cMessage(“sendHello”);
rreqRetryMsg = new cMessage(“sendRREQRetry”);
scheduleAt(simTime() + helloInterval, helloMsg);
}
void AODV::handleMessage(cMessage *msg)
{
if (msg == helloMsg)
{
sendHello();
scheduleAt(simTime() + helloInterval, helloMsg);
}
else if (msg == rreqRetryMsg)
{
sendRREQ();
scheduleAt(simTime() + rreqRetryTimeout, rreqRetryMsg);
}
else if (strcmp(msg->getName(), “RREQ”) == 0)
{
processRREQ(msg);
}
else if (strcmp(msg->getName(), “RREP”) == 0)
{
processRREP(msg);
}
else if (strcmp(msg->getName(), “RERR”) == 0)
{
processRERR(msg);
}
else if (strcmp(msg->getName(), “Hello”) == 0)
{
processHello(msg);
}
else
{
// Handle other messages
}
}
void AODV::sendHello()
{
cMessage *hello = new cMessage(“Hello”);
send(hello, “toNetworkLayer”);
}
void AODV::processHello(cMessage *msg)
{
// Implement processing of Hello message
delete msg;
}
void AODV::sendRREQ()
{
cMessage *rreq = new cMessage(“RREQ”);
send(rreq, “toNetworkLayer”);
}
void AODV::processRREQ(cMessage *msg)
{
// Implement processing of RREQ message
delete msg;
}
void AODV::sendRREP()
{
cMessage *rrep = new cMessage(“RREP”);
send(rrep, “toNetworkLayer”);
}
void AODV::processRREP(cMessage *msg)
{
// Implement processing of RREP message
delete msg;
}
void AODV::processRERR(cMessage *msg)
{
// Implement processing of RERR message
delete msg;
}
Step 4: Integrate with Simulation Model
In the network simulation model, we have to integrate the AODV module.
Network Configuration .ned File
network AODVNetwork
{
submodules:
host1: StandardHost {
parameters:
@display(“p=100,100”);
}
host2: StandardHost {
parameters:
@display(“p=300,100”);
}
// Add more hosts as needed
connections:
host1.pppg++ <–> { @display(“m=100,100”); } <–> host2.pppg++;
}
omnetpp.ini Configuration
network = AODVNetwork
*.host*.pppg[*].queue.typename = “DropTailQueue”
*.host*.ipv4.routingTable = “inet.networklayer.routing.manet.Router”
*.host*.networkLayer.networkProtocol.typename = “IPv4NetworkLayer”
*.host*.application[*].typename = “UDPBasicApp”
*.host*.application[*].destAddresses = “host1” // Set destination as needed
*.host*.application[*].destPort = 2000
*.host*.application[*].startTime = uniform(0s, 10s)
*.host*.application[*].sendInterval = uniform(1s, 2s)
*.host*.application[*].packetLength = 512B
*.host*.app[0].typename = “AODV”
Step 5: Test and Debug
- Run Simulations: We have to examine the effects of AODV module under different network conditions by implementing simulations.
- Analyze Results: Verify the correctness and performance of the execution.
- Debugging: Use debugging tools of OMNeT++ to troubleshoot any issues.
In conclusion, we offered the detailed guide to help you understand the ad hoc protocol with samples in the OMNeT++. If you need any help we can also provide you the extra details of ADOV or ad hoc through another script. For optimal implementation and simulation outcomes of ad hoc protocols in OMNeT++, feel free to reach out to our team. We offer excellent project ideas to assist you.