How to Start Adaptive Routing Projects Using OMNeT++

To start an adaptive routing project using OMNeT++, we need to replicate a network in which routing decisions modify dynamically depends on the present network conditions like traffic load, link quality, or failures. General adaptive routing protocols like Ad hoc On-demand Distance Vector (AODV) for wireless ad-hoc networks or Open Shortest Path First (OSPF) for dynamic environments. Adaptive routing mechanism, dissimilar traditional static routing and it can be changed its routing tables and paths within reply to network changes.

Below are sequential steps to get started an adaptive routing project using OMNeT++:

Steps to Start Adaptive Routing Projects in OMNeT++

Step 1: Install OMNeT++

  1. Download OMNeT++:
    • We should download and install the latest version of OMNeT++ environment on the system.
    • Adhere to the installation guidance based on the platform such as Windows, macOS, Linux.
  2. Verify Installation:
    • After installation, we go to the OMNeT++ IDE and then execute a simple instance simulation making sure that appropriately functioning.

Step 2: Create a New OMNeT++ Project

  1. Create a New Project:
    • Go to OMNeT++ IDE and select File > New > OMNeT++ Project.
    • Decide on a “Simple Project” like a base and Name it to the project like AdaptiveRouting.
  2. Define the Network Modules:
    • Make simple network modules like Router, Host, and maybe a Network module.
    • Describe the required modules like routers, links, and traffic generators within .ned files.

Example of describing a basic network including two routers and a host:

network AdaptiveRoutingNetwork {

submodules:

router1: Router;

router2: Router;

host: Host;

connections:

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

router1.ethg++ <–> EthernetInterface <–> router2.ethg++;

}

Step 3: Design the Adaptive Routing Algorithm

The adaptive routing’s crucial feature is the capability to modify the routing decisions depends on changing network conditions. We can be executed diverse kinds of adaptive routing protocols like:

  1. Traffic-based Adaptation (Load-based routing):
    • According to the network traffic loads, routes modify. For instance, a router possibly will choose a various path as a link is congested or overloaded.
  2. Link Quality-based Adaptation:
    • Depends on the links’ quality, routes alter like utilising parameters such as link bandwidth, delay, or packet loss.
  3. Hybrid Adaptation:
    • To integrate several parameters such as traffic, link quality, and delays to determine the optimal route.

Step 4: Implement Adaptive Routing Logic

  1. Routing Table:
    • Every single router will be sustained a routing table, which is modernized dynamically. The table have to include entries for destinations and the connected next hop.
    • In C++, make use of a data structure such as std::map or std::vector to save the routing table.
  2. Metrics for Adaptation:
    • Describe the parameters, which will direct the routing decisions like:
      • Link Utilization: It can be received from the volume of packets on a link.
      • Link Quality: Parameters such as delay, packet loss, and bandwidth can utilise to estimate the link quality.
      • Network Congestion: Routers possibly will adjust depends on traffic conditions or queue sizes.
  3. Decision-making Process:
    • At every single router, execute a decision-making process which confirms the present network conditions and consequently informs the routing table.
    • For instance, we may verify the load regularly at each link and then choose the smallest congested route, or if a link drop then we will update the table for preventing it.
  4. Update the Routing Table:
    • When the network conditions modify like new traffic patterns, link quality changes then the router have to modernize their routing table.
    • We need to execute a timer-based mechanism updating the routing tables periodically or activate updates rely on important changes within the network.

Example of an adaptive routing algorithm for a router in C++:

void Router::updateRoutingTable() {

// Get current link metrics (load, bandwidth, delay, etc.)

for (int i = 0; i < numLinks; ++i) {

LinkMetrics linkMetrics = getLinkMetrics(i);

// Use the metrics to decide if the route should be updated

if (linkMetrics.load > threshold) {

// Find alternative route if the current link is congested

findAlternativeRoute(i);

}

}

}

Step 5: Implement Communication Between Routers

  1. Routing Protocol Messages:
    • We describe the custom messages like RoutingUpdate or RoutingRequest to interact route updates among the routers.
    • Delineate the structure of these messages with the support of OMNeT++’s message definition files (.msg).
    • Instance of a RoutingUpdate message:

message RoutingUpdate {

int sourceId;

int destinationId;

double load;

double delay;

double packetLoss;

// Any other metrics that can impact the route decision

}

  1. Message Handling:
    • In Router module, we execute the handlers from neighbors to access incoming routing updates.
    • Based on the receiving a routing update, a router will be equated the new route data including their existing routes and modernize the routing table as required.

Example message handling in C++:

void Router::handleRoutingUpdate(RoutingUpdate *update) {

// Update the routing table if the new route is better

if (update->load < routingTable[currentDestination].load) {

routingTable[currentDestination] = update->route;

}

}

Step 6: Configure the Simulation

  1. Network Configuration:
    • Set the network to manage the simulation metrics like simulation time, link speeds, traffic generation, and so on using the omnetpp.ini file.

Example omnetpp.ini configuration:

network = AdaptiveRoutingNetwork

sim-time-limit = 100s

[Config AdaptiveRouting]

*.router*.routingProtocol = “AdaptiveRoutingProtocol”

*.host.numPackets = 1000

*.router.updateInterval = 10s

  1. Traffic Generation:
    • We need to integrate the traffic generation to experiment adaptive routing replicating network load. Make use of OMNeT++ traffic generators such as UDPBasicApp or custom traffic generators transmitting the packets via network.

Step 7: Test and Analyze the Simulation

  1. Run the Simulation:
    • Execute the simulation and monitor the adaptive routing protocol behavior within response to network changes.
    • OMNeT++ environment offers tools such as Tkenv for envisioning the network activity and observing the routers and links status.
  2. Analyze Metrics:
    • We can be recording the statistics like routing table updates, traffic load on links, and the duration adjusting to changes for the network. We need to utilise the OMNeT++ Scalar and Vector modules collecting these statistics.

Example of gathering statistics:

recordScalar(“load”, currentLoad);

  1. Visualize and Debug:
    • Debug the network with the support of the Tkenv visualization tool and then observe the dynamic changes within routing, packet forwarding, and other network metrics.
    • Verify the records for routing updates and decision-making behaviors.

Step 8: Extend the Functionality

  1. Dynamic Link Failures:
    • We need to replicate the link failures or changes within link quality observing how the routing adjusts to network modifications.
    • Execute the mechanisms to manage link failures and reroute traffic once links drop.
  2. Traffic Load Balancing:
    • We can be executed further sophisticated load balancing by delivering traffic over several routes depends on the link utilization.
  3. Hybrid Adaptive Routing:
    • Integrate several factors such as link load, delay, packet loss, in a hybrid fashion creating routing decisions.
  4. Advanced Protocols:
    • We can be executed the more advanced adaptive routing protocols for mobile ad-hoc networks,  such as AODV or OLSR (Optimized Link State Routing) in which nodes require to modernize its routes regularly rely on mobility and other network modifications.

We can improve an adaptive routing simulation by following these steps using OMNeT++ environment. The project can be further prolonged by means of inserting more sophisticated adaptive routing algorithms, managing dynamic network conditions, and then examining the routing protocol performance in various network scenarios. Drop us a message we will give you best guidance.