The goal of this lab is to get an introduction to building multi-player environments in Unity. The basic requirement for such an environment is a network connection over which the state of shared objects is synchronized (e.g. you move an object in one client and it moves in all clients!). Luckily, Unity has recently revamped their networking support (since version 5) by providing super powerful high-level networking components. In this lab you get to assemble a couple of those components to make a fully working client/server structure.
You can start by browsing the Unity Manual: Multiplayer and Networking documentation.
Unlike previous labs, this one will rely on a networking tutorial provided by someone else. Christian Arellano has done an excellent job of putting together a Unity 5 Networking Tutorial in three parts on Gamasutra (which, by the way, is an excellent resource for game developers). For Lab 8, you only need to complete part 1:
Everything you need is provided in the tutorial itself. If you are interested in the topic of networking, you can always move on to Part 2 of 3 as well (but Part 3 has not been published yet).