Getting started with installing ns-3

There are many network simulation tools available as open source and proprietary solutions. In comparison to ns-2 and other simulation tools, ns-3 offers the following features:

• The primary changes ns-2 users observe with ns-3 is the scripting language. Also, ns-2 support is limited to simple wired and Wi-Fi network simulation only.
• ns-2 programs are written in Object-oriented Tool Command Language (OTcl), whereas ns-3 programs are written in C++ or Python.
• ns-3 is open source software and has excellent support from the ns-3 team.
• ns-3 is designed as a set of modules (internet, Wi-Fi, LTE, etc.) and users can extend existing modules and add new modules.
• ns-3 is designed to be used in the command line as well as visualization mode.
• ns-3 can be easily extended with data analysis and visualization tools.
• ns-3 can be used on Linux, macOS, or Microsoft Windows operating systems.

In this section, you will start with the first hands-on task, which is installing ns-3 successfully. Let’s start by installing all necessary dependencies for ns-3:

1. Install the core dependencies for ns-3 build essentials and compilation packages:

   sudo apt-get update
   sudo apt install build-essential libsqlite3-dev libboost-all-dev libssl-dev git python3-setuptools castxml

2. Install the Python dependencies for ns-3 Python bindings:

   sudo apt install gir1.2-goocanvas-2.0 gir1.2-gtk-3.0 libgirepository1.0-dev python3-dev python3-gi python3-gi-cairo python3-pip python3-pygraphviz python3-pygccxml

3. Install the dependencies for ns-3 features support, such as NetAnimator, gdb, and valgrind:

   sudo apt install g++ pkg-config sqlite3 qt5-default mercurial ipython3 openmpi-bin openmpi-common openmpi-doc libopenmpi-dev autoconf cvs bzr unrar gdb valgrind uncrustify doxygen graphviz imagemagick python3-sphinx dia tcpdump libxml2 libxml2-dev cmake libc6-dev libc6-dev-i386 libclang-6.0-dev llvm-6.0-dev automake

Next, download the latest ns-3 version and follow the steps for installing it:

$ wget -c https://www.nsnam.org/releases/ns-allinone-3.36.tar.bz2

4. Unzip or extract the downloaded file:

   $ tar -xvjf ns-allinone-3.36.tar.bz2

5. Move to the following directory:

   $ cd ns-allinone-3.36/ns-3.36

6. Next, configure the ns-3 modules using the build system. The ns3 command (available in the ns-allinone-3.36/ns-3.36 folder) makes use of a Python wrapper around CMake. It is similar to Waf in earlier ns-3 versions. The following command configures ns-3 modules with all example and test simulation programs:

   $ ./ns3 configure --enable-examples --enable-tests

After running this command, you can verify the list of modules configured in Figure 1.1:

Figure 1.1 – The list of ns-3 modules configured

7. Next, build all the configured ns-3 modules using the following command. This command takes a while to complete:

   $ ./ns3 build

After executing the command, we can observe the list of modules linking successfully, as shown in Figure 1.2:

Figure 1.2 – ns-3 build process

8. Finally, you can check your installation by running all unit test cases provided in ns-3 modules:

   $ ./test.py

After executing this command, all test cases should either pass or be skipped. Then, a successfully installed NS-3.36 simulator is available (refer to Figure 1.3):

Figure 1.3 – ns-3 test cases execution

9. After the successful build of ns-3, you have many example simulation programs ready to execute. Try running a first example simulation with the following command and observe the output:

   $ ./ns3 run first

Now, we are executing an example ns-3 simulation, first.cc. Refer to the execution results in Figure 1.4:

Figure 1.4 – The first.cc simulation execution results

Congratulations! We have installed ns-3 successfully and tested a sample simulation. In the next section, we are going to learn how to write an ns-3 simulation program easily using Code::Blocks editor features. Thanks to the entire ns-3 team for providing detailed documentation on their website (https://www.nsnam.org) related to installing ns-3 with all features, tutorials, examples, and designs of various modules. We recommend you to go through the website for more details.