How to Begin Implement L3 protocols in NS3

To create the execution for Layer 3 (L3) protocols in NS3, we can follow this step methodically. The NS-3 is a discrete-event network replicator which delivers a solid framework for designing the Layer 3 protocols such as routing protocols, IP packet handling, and more.

Steps to Begin Implement L3 protocols in NS3

Step 1: Understand NS-3 Basics

• Explain by NS3. Download and setting NS-3 from the official site.
• Study the simple design and main mechanisms for NS3, like as nodes, devices, channels, and helpers.
• Investigate the existing L3 executions for NS-3 such as IPv4 stack, routing modules, or MPLS.

Step 2: Define Your Protocol Goals

• Define the purpose of your L3 protocol for instance routing optimization, new addressing scheme, etc.
• We are selecting the changing for existing protocol for sample OSPF, BGP or making a new one.

Step 3: Review Existing Code in NS-3

• Discover the NS-3’s L3 models:
  • IPv4 Routing: Establish in src/internet/model/.
  • Routing Protocols: For sample, AODV is in src/aodv/.
• Recognize on how the existing L3 protocols are apply to get the knowledge for essential classes and approaches.

Step 4: Plan Your Implementation

1. Packet Handling:
   • It model for the packet buildings for the protocol.
   • Express on how packets will be generated, communicated, and processed.
2. Routing Logic:
   • Packet routing for apply the decision-making process.
   • Describe the tables or data structures required for routing.
3. Integration:
   • Incorporate the protocol by the NS-3 required for IP stack.
   • State on how it interacts by Layer 2 and Layer 4.

Step 5: Create a New Protocol

• Make a directory for below the protocol src/ (e.g., src/my-protocol/).
• Improve the C++ files for estimations:
  • my-protocol-helper.h/.cc: Describe the helper class has handle the protocol.
  • my-protocol.h/.cc: Outline for key logic and data structures.
• Alter the wscript in the src/ directory for contains the new protocol.

Step 6: Implement Key Components

1. Protocol Header:
   • Describe the custom headers protocol are establish the new fields.
   • Use ns3::Header base class and execute Serialize(), Deserialize(), and Print().
2. Protocol Logic:
   • Apply the routing logic for class derived from ns3::Ipv4RoutingProtocol.
   • Override methods such as RouteOutput() and RouteInput() for packet routing.
3. Simulation Integration:
   • Use Simulator for validate the protocol by several environment.
   • Use tracing structures to log actions for debugging.

Step 7: Compile and Test

• Recreate a NS-3 to involves the protocol:

./waf configure

./waf build

• Write a replication of scripts for validate the protocol below different network environments.
• Use logging (NS_LOG) and tracing for debugging and performance analysis.

Step 8: Validate Your Implementation

• Associate the protocol’s performance against standard L3 protocols.
• Use the performance of parameter metrics such as throughput, latency, and packet delivery ratio.

Example: Adding a Custom IPv4 Routing Protocol

Here’s a sample pattern for a custom IPv4 routing protocol:

1. Header File (my-routing-protocol.h):

#include “ns3/ipv4-routing-protocol.h”

class MyRoutingProtocol : public ns3::Ipv4RoutingProtocol {

public:

static ns3::TypeId GetTypeId (void);

MyRoutingProtocol ();

virtual ~MyRoutingProtocol ();

// Implement necessary methods

};

1. Implementation File (my-routing-protocol.cc):

NS_LOG_COMPONENT_DEFINE (“MyRoutingProtocol”);

NS_OBJECT_ENSURE_REGISTERED (MyRoutingProtocol);

ns3::TypeId MyRoutingProtocol::GetTypeId () {

static ns3::TypeId tid = ns3::TypeId (“ns3::MyRoutingProtocol”)

.SetParent<ns3::Ipv4RoutingProtocol> ()

.SetGroupName (“Internet”);

return tid;

}

MyRoutingProtocol::MyRoutingProtocol () {

NS_LOG_FUNCTION (this);

}

MyRoutingProtocol::~MyRoutingProtocol () {

NS_LOG_FUNCTION (this);

}

1. Helper File (my-routing-helper.h/.cc):
   • Utilized their helper classes to simplify the addition of protocol for replicate the scripts.

Step 9: Documentation

• Document has considered the protocol plan, expectations, and limitations.
• Use explanations and markdown documents for improved the clarity.

Step 10: Advanced Enhancements

• Increase the features such as mobility handling, multi-path routing, or cross-layer optimization.
• Performance estimation use the NS3’s envision or external tools.

In the above demonstration we provide the complete simulation process procedures to execute the layer 3 routed protocols that executes in ns3 tool. If you did like to know more details regarding the layer 3 routed protocol let me know!