If I were writing an introduction to lay people, I&#x27;d probably just explain the process of loading facebook.com, something people will be very familiar with.<p>Set up a very simple home network topology.  A router&#x2F;modem, and a wired ethernet connection to a laptop.  Explain all 4 layers of the tcp&#x2F;ip model.  Explain DNS.<p>BGP seems sort of advanced for an introduction to the topic, to be honest, and so few people use smtp rather than just using gmail&#x27;s web interface, that it&#x27;s rather obscure.