Hardware firewalls are appliances designed to provide an onsite, perimeter defence for your Local Area Network. Software firewalls provide different security benefits and have different drawbacks. One thing to note is that software firewalls protect only the device running the given software, usually a desktop computer. If you are running Windows10, there is no need to spend on other firewalls since Windows Defender, which comes with Windows10 is a very good product that will protect your computer for free.
Given that network startup after a power or network interruption is a critical vulnerability period for a small, remote location to be protected, it is best that a hardware firewall be put in place in library networks.
Five firewall options for libraries are listed below. There are many more available.