How to find who make a lot of request?

Hello,
On a CentOS web server with Apache, someone make a lot of request and it make slowing server. when I disable "httpd" service then problem solve. How can I find who made a lot of request?
I find some tools like "iftop", "iptraf" and "Nethogs", but I need a tool with an output like below:
Code:interface: eth0
bps

bps % desc
544.3 1% tcp 172.16.1.5:22 <-> 172.16.1.95:8074
34.0k 87% udp 172.16.1.1:514 <-> 172.16.1.5:514
350.1 0% udp 172.16.1.5:24330 <-> 209.18.47.62:53
329.4 0% udp 172.16.1.5:34870 <-> 209.18.47.62:53
388.3 0% udp 172.16.1.5:4470 <-> 209.18.47.62:53Any idea?

Thank you.