What does port 16110 do on a Kaspa node?

Port 16110 is the RPC port on a Kaspa node — it is the channel that miners and wallets use to communicate with the node. RPC stands for Remote Procedure Call, a standard method that lets software on separate machines send commands and receive responses. If you run kaspad.exe on one PC and want a mining rig or a wallet app on another device in your home network to connect to it, you need to open port 16110 in your firewall for the kaspad.exe process (or for KDX, if you are using its built-in node). This matters because without that port open, your miner cannot submit work and your wallet cannot check balances or send transactions through your own node.