How to Implement Network Service Orchestration in NS2

To implement Network Service Orchestration in ns2, we defined to the systematic arrangement, coordination, and management of network services and resources to make sure the effective operation of complex network environments. It involves dynamically provisioning, scaling, and handling network functions and services via multiple layers of the network infrastructure. In the concept of NS2, since the tool does not characteristically support orchestration frameworks such as those in modern SDN (Software-Defined Networking) or NFV (Network Function Virtualization) environments, that can mimic the service orchestration by configuring the scenarios in which multiple network services are coordinated and handled according to the particular policies.

Below is a detailed procedure to implement the network service orchestration in ns2:

Steps to Simulate Network Service Orchestration in NS2:

  1. Set up Network Topology: Describe nodes and links that represents various parts of the network, like end devices, routers, and servers.
  2. Define Services: Replicate different kinds of network services such as routing, firewall, load balancing as applications or traffic flows.
  3. Orchestrate Service Coordination: Execute a control mechanism in the form of scripts or event-driven actions that handles the traffic and resources dynamically.
  4. Monitor Network Performance: Use trace files and logging to capture parameters and learn on how orchestration impacts network performance.
  5. Implement Dynamic Scaling or Policies: Enthusiastically adapt resources or routes in response to changes in traffic, demand, or failures.

Example: Simulating Network Service Orchestration in NS2

In this sample, we will mimic a scenario in which network services like load balancing, traffic prioritization, and dynamic routing are arranged via different nodes in the network. The orchestration logic will dynamically handle the traffic according to current network conditions, like increasing traffic load or link failures.

Example TCL Script for Simulating Network Service Orchestration:

# Create a new NS2 simulator instance

set ns [new Simulator]

# Define the output trace file for logging events

set tracefile [open service_orchestration.tr w]

$ns trace-all $tracefile

# Define the animation file for NAM (optional)

set namfile [open service_orchestration.nam w]

$ns namtrace-all $namfile

# Create network nodes: Clients, routers, load balancers, and a server

set client1 [$ns node]    # Client 1

set client2 [$ns node]    # Client 2

set load_balancer1 [$ns node] # Load Balancer 1

set load_balancer2 [$ns node] # Load Balancer 2

set router1 [$ns node]    # Router 1

set router2 [$ns node]    # Router 2

set server [$ns node]     # Server

# Create links between the nodes (representing physical network connections)

$ns duplex-link $client1 $load_balancer1 10Mb 10ms DropTail

$ns duplex-link $client2 $load_balancer1 10Mb 10ms DropTail

$ns duplex-link $load_balancer1 $router1 50Mb 10ms DropTail

$ns duplex-link $load_balancer1 $router2 50Mb 10ms DropTail

$ns duplex-link $load_balancer2 $router1 50Mb 10ms DropTail

$ns duplex-link $load_balancer2 $router2 50Mb 10ms DropTail

$ns duplex-link $router1 $server 100Mb 10ms DropTail

$ns duplex-link $router2 $server 100Mb 10ms DropTail

# Simulate service orchestration for dynamic load balancing, traffic prioritization, and fault tolerance

proc orchestrate_services {} {

global ns load_balancer1 load_balancer2 router1 router2 client1 client2

puts “Orchestrating network services…”

# Example 1: Dynamic Load Balancing

# Based on some criteria (like traffic load), switch traffic from one load balancer to another

if {[rand] < 0.5} {

puts “Balancing traffic via Load Balancer 1”

$ns at 1.0 “$ns link $client1 $load_balancer1 queue-limit 50”

$ns at 1.0 “$ns link $client2 $load_balancer1 queue-limit 50”

} else {

puts “Balancing traffic via Load Balancer 2”

$ns at 1.0 “$ns link $client1 $load_balancer2 queue-limit 50”

$ns at 1.0 “$ns link $client2 $load_balancer2 queue-limit 50”

}

# Example 2: Traffic Prioritization

# Prioritize Client 1’s traffic during peak load

if {[rand] < 0.5} {

puts “Prioritizing Client 1 traffic”

$ns at 2.0 “$ns link $client1 $load_balancer1 queue-limit 100”

$ns at 2.0 “$ns link $client2 $load_balancer1 queue-limit 30”

} else {

puts “Equally balancing traffic between Client 1 and Client 2”

$ns at 2.0 “$ns link $client1 $load_balancer1 queue-limit 50”

$ns at 2.0 “$ns link $client2 $load_balancer1 queue-limit 50”

}

# Example 3: Dynamic Routing in Case of Failure

# Simulate a link failure between Router 1 and the server and reroute traffic through Router 2

$ns at 3.0 “$ns rtmodel-at 3.0 down $router1 $server”

$ns at 3.5 “$ns rtmodel-at 3.5 up $router1 $server”

# Reroute traffic to Router 2 during the failure

puts “Rerouting traffic through Router 2”

$ns at 3.0 “$ns connect $router2 $server”

}

# Define traffic for Client 1 (TCP – File Transfer)

set tcp_client1 [new Agent/TCP]

$ns attach-agent $client1 $tcp_client1

set tcp_sink [new Agent/TCPSink]

$ns attach-agent $server $tcp_sink

$ns connect $tcp_client1 $tcp_sink

set ftp_client1 [new Application/FTP]

$ftp_client1 attach-agent $tcp_client1

# Define traffic for Client 2 (UDP – Video Streaming)

set udp_client2 [new Agent/UDP]

$ns attach-agent $client2 $udp_client2

set udp_sink [new Agent/Null]

$ns attach-agent $server $udp_sink

$ns connect $udp_client2 $udp_sink

set cbr_client2 [new Application/Traffic/CBR]

$cbr_client2 attach-agent $udp_client2

$cbr_client2 set packetSize_ 1000

$cbr_client2 set rate_ 2Mb

$cbr_client2 set interval_ 0.01

# Schedule the start of traffic

$ns at 0.5 “$ftp_client1 start”

$ns at 0.5 “$cbr_client2 start”

# Orchestrate network services dynamically

$ns at 1.0 “orchestrate_services”

# Schedule the stop time for traffic

$ns at 4.0 “$ftp_client1 stop”

$ns at 4.0 “$cbr_client2 stop”

# End the simulation at 5.0 seconds

$ns at 5.0 “finish”

# Define a finish procedure to close trace files and execute NAM for visualization

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam service_orchestration.nam &

exit 0

}

# Run the simulation

$ns run

Explanation of the Script:

  1. Network Topology:
    • We describe multiple nodes: two clients, two load balancers, two routers, and a server. The load balancers allocate traffic among routers and the server.
  2. Service Orchestration:
    • Dynamic Load Balancing: According to a random condition, the script enthusiastically shifts traffic among Load Balancer 1 and Load Balancer 2 to handle traffic load.
    • Traffic Prioritization: During peak load times, the orchestration logic selects the traffic from Client 1 such as file transfers over Client 2 like video streaming.
    • Dynamic Routing: The script replicates a link failure among Router 1 and the server and retransmits traffic via Router 2 to retain connectivity.
  3. Traffic Simulation:
    • Client 1 generates TCP traffic (file transfer via FTP) to the server.
    • Client 2 generates UDP traffic (video streaming via CBR) to the server.
  4. Service Orchestration Events:
    • The orchestration logic enthusiastically adapts queue limits, switches load balancers, and reroutes traffic according to the network conditions.
    • Link failures and restorations are mimicked to measure the orchestration system’s capability to recover from faults.
  5. Simulation Control:
    • The traffic initiates at 0.5 seconds, the service orchestration is triggered at 1.0 seconds, and the simulation execution for 5.0 seconds.
  1. Analysing the Results

The replication generates a trace file (service_orchestration.tr) that has thorough logs of network events, that has packet transmissions, drops, and service orchestration activities. We can measure the trace file to:

  • Monitor Throughput: Measure on how traffic is handled during load balancing and link failures.
  • Measure Packet Loss: Validate on how many packets were dropped because of congestion or failed links.
  • Evaluate Latency: Measure the effect of service orchestration on traffic delay.
  1. Advanced Orchestration Features

We can expand the orchestration logic by adding more advanced characteristics like:

  • Dynamic Bandwidth Allocation: Systematically distributes bandwidth according to current network demand, prioritizing high-priority services.
  • QoS-Based Orchestration: execute QoS policies that distribute resources according to the type of service such as low latency for video streaming, high throughput for file transfers.
  • Real-Time Monitoring: Use feedback loops in which real-time parameters like traffic load, latency, or packet loss enlighten the orchestration logic, that enable dynamic adjustment of network parameters.

In the presented manual, we demonstrate the comprehensive procedures to implement and execute the Network Service Orchestration that has implementation procedures explanation and sample snippets were given to execute in ns2 tool. Additional specific details regarding the Network Service Orchestration will be provided.

If you’re looking to implement any kind of Network Service Orchestration using the NS2 tool, feel free to email us with all the details. We’re here to help you achieve the best results! Our team specializes in SDN (Software-Defined Networking) and NFV (Network Function Virtualization) environments, and we can assist you with performance analysis for your projects.