How to Start BGP Protocol Projects Using NS2

To start Border Gateway Protocol (BGP) projects using NS2 that requires replicating the routing among autonomous systems (AS) by BGP. NS2 can prolong including BGP-specific functionalities as it concentrates on built-in intra-domain protocols such as RIP or OSPF. Following is a stepwise technique to get started BGP protocol projects in NS2:

Steps to Start BGP Protocol Projects in NS2

  1. Understand BGP Concepts
  • BGP (Border Gateway Protocol):
    • It is a path vector routing protocol for inter-domain routing which is among the ASes.
    • Find the optimal route to utilises the attributes such as AS_PATH, NEXT_HOP, and LOCAL_PREF.
  • Project Goals:
    • Replicate BGP routing among numerous ASes.
    • Execute and examine the BGP strategies, route advertisements, or attack scenarios like route hijacking.
  1. Set Up NS2
  1. Install NS2:
    • We should set up NS2 (version 2.35 recommended) on the system using Linux.
  2. Verify Installation:
    • We can verify with a simple simulation script, making sure that the installation is operates.
  1. Extend NS2 for BGP

While NS2 doesn’t directly support for BGP, we can prolong their functionality.

Option 1: Use BGP Extensions for NS2

  • We will need to download and set up extensions, which can integrate the functionality of BGP in NS2 like the BGP++ module.
  • Installation Steps:
    1. We should download the BGP++ patch that matching NS2.35 version.
    2. Utilise the patch to NS2:

patch -p1 < bgp_patch_file.diff

    1. Recompile NS2:

make clean

make

Option 2: Manually Implement BGP in NS2

  • In C++, we can prolong the routing protocol capabilities of NS2:
    • BGP attributes like AS_PATH, NEXT_HOP, and so on.
    • Path vector routing logic.
    • Route advertisement and selection logic.

Option 3: Use Python or MATLAB for Post-Simulation Analysis

  • In NS2, replicate the simple inter-AS communication then examine the routes or strategies with the support of Python/MATLAB.
  1. Define Project Objectives

Following is BGP’s certain features:

  1. Basic Route Advertisement:
    • Replicate the route propagation among ASes.
  2. Policy Implementation:
    • We can execute the BGP policies such as route filtering or preference rules.
  3. Attack Scenarios:
    • Mimic attack scenarios like BGP hijacking or route leaks and examines its effect.
  4. Performance Analysis:
    • Then, we need to estimate the performance parameters such as convergence time, routing table size, or protocol overhead.
  1. Design the Network Topology

In NS2, we make a network topology that has numerous ASes which is associated through the BGP routers.

Example: Interconnecting ASes

set ns [new Simulator]

set as1_r1 [$ns node]

set as2_r1 [$ns node]

set as3_r1 [$ns node]

$ns duplex-link $as1_r1 $as2_r1 10Mb 10ms DropTail

$ns duplex-link $as2_r1 $as3_r1 10Mb 10ms DropTail

  • Each AS is represented by one or more routers.
  • Define connections and routing advertisements between routers.
  1. Configure BGP Attributes and Policies

BGP utilises their features for determining the optimal path:

  • AS_PATH: Record of ASes that route pass through.
  • NEXT_HOP: It contains IP address of the next-hop router.
  • LOCAL_PREF: Priority value allocated to the routes.
  • MED (Multi-Exit Discriminator): It is frequently applied for path preference among the ASes.

Example: Implement BGP Policies

  • Prefer Shorter AS_PATH:

proc bgp_select_best_route {route1 route2} {

if {[string length $route1(as_path)] < [string length $route2(as_path)]} {

return $route1

} else {

return $route2

}

}

  • Filter Routes: From specific ASes we can obstruct the routes:

proc bgp_filter_routes {route} {

if {$route(as_path) contains “AS3”} {

return “drop”

}

return “accept”

}

  1. Add Traffic and Log Results
  1. Add Traffic Sources:
    • Replicate the interaction among the nodes under diverse ASes applying UDP or TCP traffic generators.
  2. Log Routing Decisions:
    • Log the route advertisements, decisions, and packet flows for manage the traffic.

set tracefile [open bgp-trace.tr w]

$ns trace-all $tracefile

  1. Simulate and Analyze
  1. Run the Simulation:
    • We can run the simulation using TCL script in NS2:

ns bgp_simulation.tcl

  1. Analyze Trace Files:
    • Obtain BGP routing events as of the trace file.

awk ‘{ if ($1 == “BGP_UPDATE”) print $0 }’ bgp-trace.tr

  1. Visualize Results:
    • Envision the behaviours of routing with the support of Network Animator (NAM).
    • Visualize the performance parameters like convergence time applying Python or MATLAB tools.
  1. Advanced Features
  • BGP Route Reflectors:
    • We will need to replicate the hierarchical BGP models for minimizing the volume of peer connections.
  • BGP Route Flapping:
    • Launch the unstable routes for examining the behavior of protocol.
  • BGP Security:
    • Execute and experiment the cryptographic techniques like BGPsec to protect the route updates in BGP.
  • BGP Convergence Time Analysis:
    • Estimate the duration to balance after a topology modification for routing tables.
  • Attack Simulations:
    • Mimic and examine the route hijacking or prefix leaks for attack simulation.
  1. Document Your Project

It provides complete insights that contains:

  1. Define clear project objectives and problem statement.
  2. Make a network topology and BGP sets up.
  3. Measure the simulation outcomes and analysis.
  4. Finally, it offers conclusions and future directions.

Example Project Ideas

  1. BGP Route Selection Policies:
    • Execute and equate the various BGP route selection strategies like shortest AS_PATH vs. highest LOCAL_PREF.
  2. BGP Convergence Analysis:
    • Assess the effect of network modifications on BGP convergence time for analysis.
  3. BGP Hijacking Simulation:
    • We will need to replicate a malicious AS advertising incorrect routes and also examine their effect.
  4. BGP Load Balancing:
    • Execute MED-based load balancing among several connections in BGP.
  5. Secure BGP Implementation:
    • Experiment the cryptographic mechanisms for protecting BGP route updates.

Throughout this guide, we learnt and acquire more knowledge about how to start, simulate and examine the BGP Protocol Projects within NS2 simulation environment. We can ready to offer further innovative approach on this topic, if necessary.