Little Snitch is an outgoing firewall for MacOS, i.e. it can tell you when an application tries to connect to some server and lets the user allow or disallow the connection. I want something similar for my whole network, but instead of which application is trying to connect it would tell me which device.

So for example, a web page on my Linux router listing devices on the network, and for each device listing attempted connections (domains and/or IPs) and buttons to allow/disallow the connection.

Is that something that exists, or something that can easily be put together, or would I have to write my own software?