Packettracer

Packettracer is a network simulation software. The tool from Cisco is suitable, for example, for training as an IT specialist to learn how to deal with networks and, in particular, how to behave in the event of problems. A free and open source alternative would be GNS3

Installation

You need to enable unfree and prefetch the .deb file from Packettracer before you are able to installing it. The Package is allready available for Nix. Other Unix/Linux Distros with Nix installed can installing it on their system aswell.

 $nix-store --add-fixed sha256 CiscoPacketTracer_"version"_Ubuntu_64bit.deb
 # or with
 $nix-prefetch-url --type sha256 file:///path/to/CiscoPacketTracer_"version"_Ubuntu_64bit.deb