This is showing egress traffic on a single 1Gb interface. But just the top 10 source ip's below add up to an average of over 1.5 Gbps. The 1Gb interface can't be averaging 1.5 Gb, so how would you interpret this chart.
Looks like the Top Transmitters chart. As the chart is showing both ingress and egress then it is possible to see more traffic than interface capacity. Imagine two computers sending large amount of data through this network interface. One initiates data transfer from ingress direction, the another from egress direction. The device (switch/router/firewall) reports them as Transmitters (Source Hosts) as the initiated the communication, but one is communicating in ingress direction and another in egress direction. In this situation if may appear you are over interface capacity.
