Depending on the context, we may want to limit which network interfaces polkadot listens to.
I would propose keeping something close to what parity does:
--ws-interface=[IP]
Specify the hostname portion of the WebSockets server, IP should be an interface's IP address, or all (all interfaces) or local. (default: local)
Specify the APIs available through the WebSockets interface using a comma-delimited list of API names. Possible ...