Installing NS-2 and NS-3 on Fedora

ns (Network Simulator) is a discrete-event simulator used primarily for research and educational purposes in networking. The two major versions—ns-2 and ns-3—are substantially different in architecture and usage patterns. This guide covers installation on current Fedora systems.

Installing ns-2 on Fedora

Note: ns-2 is legacy software and requires significant compatibility workarounds on modern systems. Consider ns-3 unless you need specific ns-2 functionality or existing scripts.

Prerequisites

Install base development tools and X11 libraries:

sudo dnf install gcc gcc-c++ make libX11-devel libXt-devel libXmu-devel

Download and extract

wget https://sourceforge.net/projects/nsnam/files/allinone/ns-allinone-2.34/ns-allinone-2.34.tar.gz/download -O ns-allinone-2.34.tar.gz
tar xf ns-allinone-2.34.tar.gz
cd ns-allinone-2.34

Build and install

ns-2 requires compatibility with older compiler versions. Use the modern gcc with appropriate flags:

CXX=g++ CC=gcc ./install

If you encounter build failures with modern gcc (likely), patch the code or use a container with an older compiler. Alternatively, consider using Docker with a compatible base image.

Environment configuration

Add the following to your shell configuration file (~/.bashrc for bash, ~/.zshrc for zsh):

export NS_HOME=$HOME/ns-allinone-2.34
export PATH=$NS_HOME/bin:$NS_HOME/tcl8.4.18/unix:$NS_HOME/tk8.4.18/unix:$PATH
export LD_LIBRARY_PATH=$NS_HOME/otcl-1.13:$NS_HOME/ns-2.34/lib:/usr/local/lib:$LD_LIBRARY_PATH
export TCL_LIBRARY=$NS_HOME/tcl8.4.18/library

Reload your shell configuration:

source ~/.bashrc

Verify installation:

nam
ns

Installing ns-3 on Fedora

ns-3 is the recommended choice for new projects. It features a cleaner C++ API and better maintainability.

Prerequisites

Install required dependencies:

sudo dnf install libxml2 libxml2-devel gcc gcc-c++ make automake autoconf \
  binutils openssh-clients openssl python3 python3-devel mercurial scons \
  flex bison tcpdump valgrind gdb sqlite-devel

For additional Python bindings support, also install:

sudo dnf install python3-dev

Download and extract

mkdir -p ~/ns-workspace
cd ~/ns-workspace
wget https://www.nsnam.org/release/ns-allinone-3.42.tar.bz2
tar xjf ns-allinone-3.42.tar.bz2
cd ns-allinone-3.42

(Replace 3.42 with the latest stable version available)

Build

./build.py

This script downloads and configures ns-3 along with dependencies. Proceed to the ns-3 directory:

cd ns-3.42

Configure with Waf

Configure for optimized builds with examples enabled:

./waf -d optimized configure --enable-examples
./waf

For development builds with debugging symbols:

./waf configure
./waf

Validate installation

Run an example simulation:

./waf shell
cd build/optimized/examples
./udp/udp-echo

Inspect the generated pcap trace file:

tcpdump -tt -r udp-echo-0-1.pcap

Or view with more detail:

tcpdump -tt -r udp-echo-0-1.pcap -v

Running Python scripts

ns-3 supports Python-based simulations. Create a simple test script:

#!/usr/bin/env python3
import sys
sys.path.insert(0, '/path/to/ns-3.42/build/optimized/bindings/python')

import ns.core as ns_core
import ns.network as ns_network
import ns.internet as ns_internet

def main():
    ns_core.LogComponentEnable("UdpEchoServerApplication", ns_core.LOG_LEVEL_INFO)
    ns_core.LogComponentEnable("UdpEchoClientApplication", ns_core.LOG_LEVEL_INFO)

    ns_core.Simulator.Stop(ns_core.Seconds(10.0))
    ns_core.Simulator.Run()
    ns_core.Simulator.Destroy()

if __name__ == "__main__":
    main()

Run it with:

./waf shell python3 your_script.py

Troubleshooting

ns-2 compilation failures: Modern gcc versions may reject ns-2’s code. Options include using --std=gnu++98 flags or running ns-2 in a container based on Fedora 15 or CentOS 6.

Missing modules in ns-3: If examples don’t build, ensure all optional dependencies are installed. Check the configure output for warnings about missing features.

Python bindings not found: Ensure you’re running scripts with ./waf shell to set up the correct library paths.

Performance: For large simulations, build with optimization flags and allocate sufficient RAM. Monitor with htop or vmstat.