What are the replacements of `inetd` and `/etc/inetd.conf` in Ubuntu?

inetd is a service dispatcher for services recorded in /etc/inetd.conf. In Lubuntu 18.04, there is no /etc/inetd.conf. ps -A | grep inetd returns nothing. What are the replacements of inetd and /etc/inetd.conf? I do not have /etc/xinetd*. Thanks.