A modern business is made up of dozens, often hundreds, of individual devices, computers, appliances used by the company and employees. Some host websites and resources, others are personal endpoints, and some are resources shared by entire departments or the business as a whole. All of these physical technological assets come together to form your businesses' overall network made up of connected devices. In fact, everything that your central router provides with a local IP address, not matter how small or seemingly insignificant, technically counts as a piece of your network, can use up bandwidth and resources, and can create vulnerabilities in your system if not properly monitored and secured.
