What does netstat tell you?
[jpaglia@core2pclinux Documents]$ su -c "netstat -anutp"
Password:
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:30020 0.0.0.0:* LISTEN 3625/python
tcp 0 0 0.0.0.0:6566 0.0.0.0:* LISTEN 1946/xinetd
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 3423/sshd
tcp 0 0 0.0.0.0:631 0.0.0.0:* LISTEN 3429/cupsd
tcp 0 0 0.0.0.0:17500 0.0.0.0:* LISTEN 4047/dropbox
tcp 0 0 172.23.62.243:47521 74.125.226.86:443 ESTABLISHED 4840/firefox
tcp 38 0 172.23.62.243:48969 75.126.110.53:443 CLOSE_WAIT 4047/dropbox
tcp 0 0 172.23.62.243:42569 10.10.4.31:22 ESTABLISHED 6691/ssh
tcp 0 0 172.23.62.243:42544 74.125.226.64:80 ESTABLISHED 4840/firefox
tcp 0 0 172.23.62.243:37893 74.125.226.88:443 ESTABLISHED 4840/firefox
tcp 38 0 172.23.62.243:46569 208.43.202.51:443 CLOSE_WAIT 4047/dropbox
tcp 0 0 172.23.62.243:56291 208.43.202.5:80 ESTABLISHED 4047/dropbox
tcp 0 0 172.23.62.243:54072 74.125.226.80:443 ESTABLISHED 4840/firefox
tcp 0 0 172.23.62.243:42548 50.19.126.232:80 ESTABLISHED 4840/firefox
tcp 0 0 172.23.62.243:42533 74.125.226.64:80 ESTABLISHED 4840/firefox
tcp 38 0 172.23.62.243:35095 50.19.116.103:443 CLOSE_WAIT 4047/dropbox
tcp 0 0 172.23.62.243:40092 74.125.226.65:80 ESTABLISHED 4840/firefox
tcp 0 0 172.23.62.243:47043 172.23.62.51:3389 ESTABLISHED 4390/rdesktop
tcp 0 0 :::22 :::* LISTEN 3423/sshd
tcp 0 0 :::631 :::* LISTEN 3429/cupsd
udp 0 0 0.0.0.0:5353 0.0.0.0:* 3354/avahi-daemon:
udp 0 0 0.0.0.0:1900 0.0.0.0:* 3625/python
udp 0 0 0.0.0.0:43012 0.0.0.0:* 3354/avahi-daemon:
udp 0 0 0.0.0.0:68 0.0.0.0:* 3088/dhclient
udp 0 0 0.0.0.0:17500 0.0.0.0:* 4047/dropbox
udp 0 0 0.0.0.0:39517 0.0.0.0:* 3625/python
udp 0 0 0.0.0.0:13932 0.0.0.0:* 3088/dhclient
udp 0 0 0.0.0.0:631 0.0.0.0:* 3429/cupsd
udp 0 0 :::28582 :::* 3088/dhclient
[jpaglia@core2pclinux Documents]$
Take out the "n" to see names (takes longer to run)...