How to Simulate Wireless Mesh Topology Projects Using NS2

To simulate Wireless Mesh Topology using NS2 that includes configuring wireless nodes in a mesh configuration in which every node is capable of communicating directly with its neighbouring nodes. The nodes form a dynamic self-healing network including multi-hop communication. Wireless mesh networks are generally utilized in disaster recovery, community networks, and military applications.

The network environment NS2 has wireless simulation capabilities with modules, which replicate multiple features of wireless networks that containing node mobility, routing protocols, and signal interference.

For those seeking expert advice on project performance, phdprime.com offers comprehensive guidance aimed at achieving optimal results. We provide detailed, step-by-step instructions for simulating Wireless Mesh Topology Projects using NS2, along with personalized research assistance from the dedicated team at phdprime.com.

Here’s how to simulate a Wireless Mesh Topology project using NS2:

Steps to Simulate Wireless Mesh Topology Projects in NS2

1. Set up NS2 Environment:

Make sure NS2 is installed and working correctly on the system. To replicate wireless mesh networks, we will require using the wireless functionalities of NS2 that contains wireless node configuration, mobility models, and routing protocols.

2. Understanding Wireless Mesh Topology:

• In a Wireless Mesh Topology, nodes communicate directly with neighbouring nodes. Each node performs as a relay for other nodes, which enabling multi-hop communication.
• The network is self-healing: if a node fails then the traffic is rerouted via other nodes in the mesh.
• Nodes may be stationary or mobile that relying on the use case.

3. Create a TCL Script for Wireless Mesh Topology:

Here is a TCL script to replicate a Wireless Mesh Topology with 6 wireless nodes in NS2:

# Create a new simulator instance

set ns [new Simulator]

# Define the type of channel used in the wireless network

set opt(chan)           Channel/WirelessChannel

set opt(prop)           Propagation/TwoRayGround

set opt(netif)          Phy/WirelessPhy

set opt(mac)            Mac/802_11

set opt(ifq)            Queue/DropTail/PriQueue

set opt(ll)             LL

set opt(ant)            Antenna/OmniAntenna

set opt(x)              500     ;# X dimension of the simulation area

set opt(y)              500     ;# Y dimension of the simulation area

set opt(ifqlen)         50      ;# Max packets in the interface queue

set opt(seed)           0.0     ;# Seed for random number generation

set opt(adhocRouting)   AODV    ;# Ad-hoc routing protocol (e.g., AODV)

set opt(nn)             6       ;# Number of nodes

set opt(stop)           20.0    ;# Simulation stop time

# Define the node movement model

set opt(cp) “cbr”       ;# Traffic type (constant bit rate)

# Create the topography object

create-god $opt(nn)

# Set up the initial network topology

$ns node-config -adhocRouting $opt(adhocRouting) \

-llType $opt(ll) \

-macType $opt(mac) \

-ifqType $opt(ifq) \

-ifqLen $opt(ifqlen) \

-antType $opt(ant) \

-propType $opt(prop) \

-phyType $opt(netif) \

-channelType $opt(chan) \

-topoInstance [new Topography] \

-wiredRouting OFF \

-agentTrace ON \

-routerTrace ON \

-macTrace ON \

-movementTrace OFF

# Configure the wireless nodes

set topo [new Topography]

$topo load_flatgrid $opt(x) $opt(y)

# Create the nodes

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

set node_($i) [$ns node]

}

# Set node positions manually (or you can randomize the positions)

$node_(0) set X_ 50.0

$node_(0) set Y_ 50.0

$node_(0) set Z_ 0.0

$node_(1) set X_ 100.0

$node_(1) set Y_ 50.0

$node_(1) set Z_ 0.0

$node_(2) set X_ 150.0

$node_(2) set Y_ 50.0

$node_(2) set Z_ 0.0

$node_(3) set X_ 100.0

$node_(3) set Y_ 100.0

$node_(3) set Z_ 0.0

$node_(4) set X_ 50.0

$node_(4) set Y_ 100.0

$node_(4) set Z_ 0.0

$node_(5) set X_ 150.0

$node_(5) set Y_ 100.0

$node_(5) set Z_ 0.0

# Define the traffic generation using CBR (Constant Bit Rate) over UDP

for {set i 0} {$i < 5} {incr i} {

set udp($i) [new Agent/UDP]

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

set null($i) [new Agent/Null]

$ns attach-agent $node_([expr $i + 1]) $null($i)

$ns connect $udp($i) $null($i)

set cbr($i) [new Application/Traffic/CBR]

$cbr($i) attach-agent $udp($i)

$cbr($i) set packetSize_ 512

$cbr($i) set rate_ 100Kb

# Schedule the traffic

$ns at 1.0 “$cbr($i) start”

}

# Stop traffic after 15 seconds

for {set i 0} {$i < 5} {incr i} {

$ns at 15.0 “$cbr($i) stop”

}

# Stop the simulation

$ns at $opt(stop) “finish”

# Procedure to finish the simulation

proc finish {} {

global ns nf

$ns flush-trace

close $nf

exec nam out.nam &

exit 0

}

# Run the simulation

$ns run

4. Explanation of the Code:

• Channel Type: The wireless communication channel is configuring utilizing a WirelessChannel object with the TwoRayGround propagation model.
• Node Configuration: The nodes are set up as wireless nodes using the 802.11 MAC protocol, AODV (Ad-hoc On-demand Distance Vector) as the routing protocol, and OmniAntenna as the antenna type.
• Node Placement: Six nodes (node_(0) to node_(5)) are positioned manually at distinct locations in the simulation area (500×500 units).
• Traffic Generation: Constant Bit Rate (CBR) traffic is made over UDP among several nodes. The traffic begins at 1 second and ends at 15 seconds.
• Simulation End: The simulation ends at 20 seconds, and the outcomes are saved to a .nam file for visualization.

5. Run the Simulation:

1. We can save the script as wireless_mesh_topology.tcl.
2. Open a terminal and navigate to the directory in which script is saved.
3. We can execute the simulation using:

ns wireless_mesh_topology.tcl

1. The simulation will make an out.nam file, which we can envision utilizing Network Animator (NAM).

6. Visualization in NAM:

• Open the out.nam file in NAM to envision the wireless mesh topology. We will observe six wireless nodes are located within the grid, with traffic flowing among them according to the CBR traffic schedule.
• Also, we will monitor the routing among the nodes as the AODV routing protocol dynamically discovers routes in the mesh network.

7. Customization and Enhancements:

• Increase Node Count: We can maximize the amount of wireless nodes by inserting additional nodes in for loop and describing their positions.
• Mobility Models: We can insert mobility to the nodes by identifying movement patterns. For instance:

$node_(0) setdest 150 150 5

• Routing Protocols: We can test with distinct ad-hoc routing protocols like DSR (Dynamic Source Routing) or OLSR (Optimized Link State Routing):

set opt(adhocRouting) DSR

• Performance Metrics: We can allow tracing for performance analysis, like calculating throughput, delay, and packet loss:

set tracefile [open trace.tr w]

$ns trace-all $tracefile

8. Performance Analysis:

To examine the performance of the wireless mesh topology:

• Throughput: Calculate the amount of data effectively sent among nodes.
• Latency: Assess the delay of data traveling across several hops in the mesh network.
• Packet Loss: Examine the reliability of communication within the mesh topology that specifically under high traffic loads or node failures.

Through this process, we successfully executed the simulation methods for Mesh Topology Projects, simulated and analyse its performances in NS2 virtual environment. If you have any requirement about the projects, we can offer you.