How to Start Fibre Channel Arbitrated Topology Projects Using NS2

To start replicating a Fibre Channel Arbitrated Loop (FC-AL) topology using NS2 (Network Simulator 2) that need to execute a ring-based interaction system in which devices like storage devices, servers are distribute general interaction channel. FC-AL is typically utilised within storage area networks (SANs) and high-performance computing.

Below is a step-by-step mechanism to get starting the Fibre Channel Arbitrated Loop Topology project in NS2:

Steps to Start FC-AL Topology in NS2

  1. Understand Fibre Channel Arbitrated Loop
  • Structure:
    • In logical loop, devices are associated.
    • Data moves in one direction via loop.
    • Arbitration makes sure that only one device can be sent at a time.
  • Applications:
    • High-performance distributed interaction situations.
    • Storage area networks (SANs).
  1. Set Up NS2
  1. Install NS2: We should properly install NS2 on the system.

sudo apt-get install ns2

  1. Verify Installation: Confirm installation with sample simulation script:

ns example.tcl

  1. Define FC-AL Topology
  • Make nodes to signify the Fibre Channel devices.
  • Associate the nodes within a unidirectional ring.
  1. TCL Script for FC-AL Topology

Here’s an instance of TCL script for replicating an FC-AL Topology:

TCL Script Example

# Initialize NS2 Simulator

set ns [new Simulator]

set tracefile [open fc_al_topology.tr w]

$ns trace-all $tracefile

# Define number of nodes in the loop

set num_nodes 5

# Create nodes

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

set n($i) [$ns node]

}

# Create unidirectional links to form a loop

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

set next [expr ($i + 1) % $num_nodes]

$ns simplex-link $n($i) $n($next) 1Gb 1ms DropTail

}

# Attach agents for traffic simulation

# Example: Node 0 sends data to Node 3

set tcp0 [new Agent/TCP]

$ns attach-agent $n(0) $tcp0

set sink0 [new Agent/TCPSink]

$ns attach-agent $n(3) $sink0

$ns connect $tcp0 $sink0

# Add a traffic generator

set ftp [new Application/FTP]

$ftp attach-agent $tcp0

# Start traffic

$ns at 1.0 “$ftp start”

# End simulation

$ns at 5.0 “finish”

proc finish {} {

global ns tracefile

$ns flush-trace

close $tracefile

exit 0

}

$ns run

  1. Key Features to Simulate
  1. Arbitration:
    • We need to replicate the Fibre Channel arbitration for loop access.
  2. Performance Metrics:
    • Throughput: Estimate the ratio of data delivery through the loop.
    • Latency: Examine delays that are trigged by arbitration and data propagation.
    • Fairness: Measure access fairness between the devices.
  1. Enhancing Arbitration Mechanism

Fibre Channel arbitration can be replicated through managing packet scheduling:

  • Execute a token-based access control approach.
  • Make sure that only one device sends at a time.

Example:

proc fc_arbitration {src dst packet} {

global token_holder

if {$src == $token_holder} {

transmit $packet

# Pass token to next node

set token_holder [expr ($src + 1) % $num_nodes]

} else {

drop $packet

}

}

  1. Analyze Trace File
  • Measure the performance of network to utilize the trace file as fc_al_topology.tr.
  • Obtain certain performance parameters like:
    • Throughput:

grep “tcp” fc_al_topology.tr > throughput.log

    • Dropped Packets:

grep “drop” fc_al_topology.tr > dropped_packets.log

  1. Visualize Results

We need to utilize Gnuplot or another graphing tool for visualization:

  1. Throughput Graph:

set title “Fibre Channel Throughput”

plot “throughput.log” using 1:2 with lines title “Throughput”

  1. Latency Graph:
    • Envision the delays for diverse nodes.
  1. Extend the Simulation
  2. Dynamic Node Behavior
  • Replicate the dynamic addition or elimination of nodes:

$ns at 3.0 “$ns simplex-link $n(5) $n(0) 1Gb 1ms DropTail”

  1. Simulate Node Failures
  • We should replicate a node or link failure for observing the loop resiliency:

$ns at 2.5 “$ns reset-links $n(1) $n(2)”

  1. Implement Advanced Features
  • Integrate traffic models for replicating the real-world SAN loads.
  • Test with Fibre Channel classes of service for execution.
  1. Modify NS2 Core for Advanced Features

For a realistic FC-AL simulation, we can explore advanced aspects like:

  1. Token-Based Arbitration:
    • Alter the recv() method using C++ core for executing the token passing arbitration.
  2. Flow Control:
    • Execute flow control, making sure buffer management at every single node.

Tools and Resources

  • Wireshark: We need to examine the Fibre Channel traffic models using Wireshark tools.
  • Gnuplot: These tools designed for envisioning the performance parameters such as throughput and delay.
  • NS2 Documentation: Recommendation to execute the advanced aspects of this topology.

In this given module, we had explicitly concentrated the novel information on how to simulate and extend the Fibre Channel Arbitrated Topology Projects that was executed using NS2 platform. If you need more specifies regarding this mechanisms we will explain it based on your requirements.