root@engdebian:~# lsof -i

COMMAND   PID        USER   FD   TYPE DEVICE SIZE NODE NAME
exim4    1726 Debian-exim    0u  IPv4   2397       TCP localhost.localdomain:smtp (LISTEN)
lpd      1742      daemon    6u  IPv4   2427       TCP *:printer (LISTEN)
sshd     1813        root    3u  IPv6   2750       TCP *:ssh (LISTEN)
dhclient 2085        root    9u  IPv4   3037       UDP *:bootpc 
pine     2195      alexei    3u  IPv4   3276       TCP 192.168.1.101:1024->soemail.rutgers.edu:imaps (ESTABLISHED)
ssh      2229      alexei    3u  IPv4   4215       TCP 192.168.1.101:1040->coewww.rutgers.edu:ssh (ESTABLISHED)