bandwhich sniffs a given network interface and records IP packet size, cross referencing it with the /proc filesystem on linux or lsof on MacOS. It is responsive to the terminal window size, displaying less info if there is no room for it. It will also attempt to resolve ips to their host name in the background using reverse DNS on a best effort basis.

This looks much better than me fumbling through lsof’s man page for ten minutes and then giving up.