Have you tried using Netflow monitoring?
You could monitor the IP traffic by using the NetFlow protocol. This protocol allows to you review the traffic's most useful patterns and general data.
'NetFlow' is a network protocol, developed by Cisco Systems to collect IP traffic information. It has become an industrial standard for network traffic monitoring and is currently supported by several platforms besides Cisco's IOS and NXOS like Juniper devices, Enterasys Switches and operating systems like Linux, FreeBSD, NetBSD and OpenBSD.
If a NetFlow capable router is not available, but you use a Linux server to route your traffic, you may install a NetFlow software probe which sends all NetFlow-related information to its server.
In Linux there is a program called fprobe
which obtains the traffic and sends it to a NetFlow Server. By this program you're able to generate NetFlow traffic which goes through its interfaces, e.g.:
/usr/sbin/fprobe -ieth0 -fip 192.168.1.185:9995
Once the traffic has been generated, you're able to review the traffic's statistics by entering the following command:
nfdump -R /home/netflow_data/