Your network topology is the physical and logical arrangement of devices within your local network. There are 7 network topologies: Point-to-point, Bus, Ring, Star, Tree, Mesh, and Hybrid.
Star is the most common network topology. If you are using a basic network setup with a router, a switch or two, and a handful of Windows workstations, you are using a star topology.
If you want to understand what you need to secure, you first need to understand the layout and connections. Therefore, you should start by creating a basic map of your network infrastructure.
To start, draw a rough diagram of the locations of your devices and their connections. This does not have to be perfect; you only need to document the location of every device and connection.
You can draw the map out with a pen and paper or use a free digital tool. Whenever I need to draw out a diagram, I use draw.io, an easy-to-use free tool with online and desktop versions.
Network diagrams can also be created using software tools. These diagrams will include more details about your networking topology, including IP information. You can consider purchasing higher-end software with network mapping capabilities, such as SolarWinds, if you wish.
However, free tools are also available for network mapping. The free version of Intermapper is an option, and you can upgrade to a professional license if desired. Intermapper will assemble an elementary map of the logical connections on your network. You can combine this logical map with your physical map to get the best overview of your network setup.
Once you have made a comprehensive map of your network infrastructure, you will be able to get a better understanding of its structure and identify areas to investigate security vulnerabilities. Make sure to save the network map as documentation. It is recommended to update the map whenever significant changes are made to your network.