How to Calculate Network Path Latency in omnet++
To calculate the network path latency in OMNeT++ has needs to evaluate the total time it takes for a packet to travel from a source node to a destination node along a particular path via the network and this encompasses the delays that familiarized by all intermediate nodes and links like the transmission delay, propagation delay, processing delay, and queuing delay. The below are the procedures on how to calculate the network path latency in OMNeT++:
Steps to Calculate Network Path Latency in OMNeT++:
- Set Up the Network Model:
- Describe network topology in OMNeT++ using NED files and contains to setting up nodes, links with particular data rates and delays, and routing protocols.
- Implement Traffic Generation:
- Use modules such as UdpApp, TcpApp, or custom application modules to create traffic in network and make sure those packets are sent from the source node to the destination node via the path to evaluate.
- Track Packet Send and Receive Times:
- To calculate path latency we need to monitor the time when a packet is sent from the source and the time when it is received at the destination.
- Calculate Path Latency:
- The path latency for a packet can be intended using the formula: Path Latency=Receive Time at Destination−Send Time at Source\text{Path Latency} = \text{Receive Time at Destination} – \text{Send Time at Source}Path Latency=Receive Time at Destination−Send Time at Source
- We need to estimate the average path latency over multiple packets for a more comprehensive measure.
Example Implementation:
The bellow is the sample of how to calculate path latency in OMNeT++:
#include <omnetpp.h>
using namespace omnetpp;
class SourceNode : public cSimpleModule {
private:
simsignal_t sendTimeSignal; // Signal to track send time
protected:
virtual void initialize() override {
// Register signal for send time
sendTimeSignal = registerSignal(“sendTime”);
// Schedule the first packet send
scheduleAt(simTime() + par(“sendInterval”).doubleValue(), new cMessage(“sendPacket”));
}
virtual void handleMessage(cMessage *msg) override {
if (strcmp(msg->getName(), “sendPacket”) == 0) {
// Create and send a packet
cMessage *packet = new cMessage(“dataPacket”);
simtime_t sendTime = simTime();
packet->setTimestamp(sendTime); // Record the send time
send(packet, “out”);
// Schedule the next packet send
scheduleAt(simTime() + par(“sendInterval”).doubleValue(), new cMessage(“sendPacket”));
// Emit the send time signal
emit(sendTimeSignal, sendTime);
delete msg; // Delete the sendPacket message after sending
}
}
};
class DestinationNode : public cSimpleModule {
private:
simsignal_t pathLatencySignal; // Signal to track path latency
protected:
virtual void initialize() override {
// Register signal for path latency
pathLatencySignal = registerSignal(“pathLatency”);
}
virtual void handleMessage(cMessage *msg) override {
if (strcmp(msg->getName(), “dataPacket”) == 0) {
// Calculate path latency
simtime_t receiveTime = simTime();
simtime_t sendTime = msg->getTimestamp();
simtime_t pathLatency = receiveTime – sendTime;
// Emit the path latency signal
emit(pathLatencySignal, pathLatency);
// Process the received packet (e.g., forward or delete)
delete msg;
}
}
};
Define_Module(SourceNode);
Define_Module(DestinationNode);
Explanation:
- SourceNode Module:
- initialize() Function: Registers a signal to monitor the time when packets are sent and also schedules the first packet transmission.
- handleMessage() Function: Sends a packet with the current simulation time recorded as a timestamp. The packet is then forwarded to the next module like intermediate nodes or directly to the destination. The send time is emitted as a signal.
- DestinationNode Module:
- initialize() Function: Registers a signal to track path latency.
- handleMessage() Function: When a packet is received, the current time is compared with the timestamp recorded when the packet was sent. The difference among these two times is the path latency, which is then released as a signal.
- Run the Simulation:
- Compile and run OMNeT++ project. The simulation will test the path latency for each packet, and these latencies will be recorded as signals.
- Analyze and Interpret Results:
- Use OMNeT++’s built-in tools (like opp_scavetool) or export the recorded signals to evaluate the path latency and we need to compute the average path latency, maximum latency, and other relevant statistics to measure the performance of the network path.
Additional Considerations:
- Intermediate Nodes: If the network encompasses intermediate nodes like routers, make sure that the delays familiarized by these nodes like queuing and processing delays are considered in the path latency calculation.
- Traffic Patterns: this kind of traffic like burst, constant bit rate and network load can importantly affect the path latency. Experiment with diverse scenarios to see how the latency changes.
- Network Conditions: Network congestion, link failures, or routing changes can affect the path latency, so consider these factors when measuring the outcomes.
We clearly learned and demonstrate how to calculate and measure the network path latency using the OMNeT++ tool and we also offer the more additional data regarding the path latency.
Let us know your parameter details, and we’ll deliver the best simulation performance results for Network Path Latency using the OMNeT++ tool.