How to Implement Address Protocol in NS2

 

To implement an “Address Protocol” within NS2 is rather ambiguous since the “address protocol” can be referred to various concepts relying on the context, like address resolution, address allocation, or routing protocols according to the addressing schemes.

Given the ambiguity, we will framework a simple method to executing a protocol within NS2 which deals with network address management, like basic custom protocol for address allocation or a simple version of ARP that is Address Resolution Protocol.

Step 1: Define the Protocol Requirements

Before execution, we decide what particular aspect of “address protocol” we desire to simulate. For instance:

  1. Address Resolution Protocol (ARP): Resolves IP addresses to the MAC addresses.
  2. Dynamic Address Allocation: Assigns IP addresses dynamically in a network.
  3. Custom Address-Based Routing: A routing protocol that uses particular addressing schemes.

Step 2: Set Up NS2

Make sure that NS2 is installed on the system. Check the installation by running a simple simulation.

Step 3: Implement the Address Protocol in C++

  1. Implementing ARP-Like Protocol (Address Resolution)

Here’s, how we may execute a simple ARP-like protocol that resolves the IP addresses to MAC addresses:

#include <agent.h>

#include <packet.h>

#include <trace.h>

#include <address.h>

#include <map>

class ARPAgent : public Agent {

public:

ARPAgent();

void recv(Packet* p, Handler* h);

void resolveAddress(int ipAddr);

void replyToAddressResolution(int ipAddr, int macAddr);

protected:

std::map<int, int> arpTable_; // IP Address -> MAC Address

};

// Constructor

ARPAgent::ARPAgent() : Agent(PT_UDP) {

// Initialization code here

}

// Packet reception

void ARPAgent::recv(Packet* p, Handler* h) {

hdr_ip* iph = hdr_ip::access(p);

int ipAddr = iph->src();

if (arpTable_.find(ipAddr) == arpTable_.end()) {

resolveAddress(ipAddr);

} else {

// Process the packet as the address is already resolved

}

}

// Resolve IP address to MAC address

void ARPAgent::resolveAddress(int ipAddr) {

// Send an ARP request (in this context, just simulate resolution)

int macAddr = ipAddr + 1000; // Example resolution logic

arpTable_[ipAddr] = macAddr;

// Simulate sending an ARP reply

replyToAddressResolution(ipAddr, macAddr);

}

// Handle ARP reply

void ARPAgent::replyToAddressResolution(int ipAddr, int macAddr) {

// Add the resolved address to the ARP table

arpTable_[ipAddr] = macAddr;

}

  1. Implementing a Simple Dynamic Address Allocation Protocol

Here’s how we may execute a simple dynamic address allocation protocol in which the central node allocates IP addresses to other nodes:

#include <agent.h>

#include <packet.h>

#include <trace.h>

#include <address.h>

#include <map>

class AddressAllocAgent : public Agent {

public:

AddressAllocAgent();

void recv(Packet* p, Handler* h);

void allocateAddress(int nodeId);

protected:

std::map<int, int> addressTable_; // Node ID -> IP Address

int nextAvailableAddress_;

};

// Constructor

AddressAllocAgent::AddressAllocAgent() : Agent(PT_UDP), nextAvailableAddress_(1) {

// Initialization code here

}

// Packet reception

void AddressAllocAgent::recv(Packet* p, Handler* h) {

// Example of receiving a request for address allocation

hdr_cmn* cmnh = hdr_cmn::access(p);

int nodeId = cmnh->next_hop_;

if (addressTable_.find(nodeId) == addressTable_.end()) {

allocateAddress(nodeId);

} else {

// Address already allocated, no need for further action

}

}

// Allocate IP address to a node

void AddressAllocAgent::allocateAddress(int nodeId) {

addressTable_[nodeId] = nextAvailableAddress_++;

// Simulate sending the assigned IP address back to the node

}

Step 4: Integrate the Protocol into NS2

  1. Modify the Makefile: Append the new protocol class such as ARPAgent, AddressAllocAgent to the NS2 Makefile so as to it obtains compiled with the rest of the simulator.
  2. Recompile NS2:

make clean

make

Step 5: Create a Tcl Script to Simulate the Protocol

When the protocol is executed and compiled, make a Tcl script to replicate a network using the custom protocol.

Example Tcl Script for ARP-Like Protocol:

# Create a simulator object

set ns [new Simulator]

# Define the topology

set val(chan)   Channel/WirelessChannel

set val(prop)   Propagation/TwoRayGround

set val(netif)  Phy/WirelessPhy

set val(mac)    Mac/802_11

set val(ifq)    Queue/DropTail/PriQueue

set val(ll)     LL

set val(ant)    Antenna/OmniAntenna

set val(ifqlen) 50

set val(nn)     10

set val(x)      1000

set val(y)      1000

set val(stop)   100.0

set val(rp)     ARP   ;# Address Resolution Protocol

# Initialize the topology object

set topo [new Topography]

$topo load_flatgrid $val(x) $val(y)

# Create the God object

create-god $val(nn)

# Configure the nodes

$ns node-config -adhocRouting $val(rp) \

-llType $val(ll) \

-macType $val(mac) \

-ifqType $val(ifq) \

-ifqLen $val(ifqlen) \

-antType $val(ant) \

-propType $val(prop) \

-phyType $val(netif) \

-channelType $val(chan) \

-topoInstance $topo \

-agentTrace ON \

-routerTrace ON \

-macTrace ON \

-movementTrace ON

# Create nodes

for {set i 0} {$i < $val(nn)} {incr i} {

set node_($i) [$ns node]

}

# Define node positions and movement model

$node_(0) set X_ 100.0; $node_(0) set Y_ 200.0

$node_(1) set X_ 200.0; $node_(1) set Y_ 300.0

$node_(2) set X_ 300.0; $node_(2) set Y_ 400.0

$node_(3) set X_ 400.0; $node_(3) set Y_ 500.0

$node_(4) set X_ 500.0; $node_(4) set Y_ 600.0

# Set up traffic sources

set udp [new Agent/UDP]

$ns attach-agent $node_(0) $udp

set null [new Agent/Null]

$ns attach-agent $node_(4) $null

$ns connect $udp $null

set cbr [new Application/Traffic/CBR]

$cbr attach-agent $udp

$cbr set packetSize_ 512

$cbr set interval_ 0.1

$cbr start

# Simulation end

$ns at $val(stop) “stop”

$ns at $val(stop) “$ns nam-end-wireless $val(stop)”

$ns at $val(stop) “exit 0”

proc stop {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

}

# Run the simulation

$ns run

Step 6: Run the Simulation

  1. We can save the Tcl script like address_protocol_example.tcl.
  2. Open a terminal and transfer to the directory in which we saved the Tcl script.
  3. Run the simulation using the below command:

ns address_protocol_example.tcl

Step 7: Analyse the Results

  • We can use the trace files and the network animator (NAM) to evaluate the performance of the protocol, concentrating on the parameters like address resolution time, successful address allocation, and overall network performance.

Additional Considerations

  • Protocol Customization: Relying on the particular requires, we may need to tailor the protocol logic to manage certain scenarios, like dynamic IP allocation or ARP cache management.
  • Performance Comparison: If we are executing a new addressing scheme, compare its performance versus traditional protocols such as DHCP or ARP to estimate its effectiveness.

We have given a summary about the Address Protocol that were executed and analysed using the above procedure in the simulation ns2. Additional specifies will be shared if you required.

We will walk you through every step of implementing the Address Protocol in NS2. For the best project topics, visit ns2project.com, where we’ll help you discover the most exciting project ideas!