How can I measure throughput for ADC licensing?

The Edgenexus ADC is licensed by throughput: 3 Gbps, 6 Gbps, and Unlimited.

So, how can I measure the throughput through my firewall and within the LAN to my application servers in order to size my license appropriately?

You can look at using 3rd party software products such as NTOPNG (https://www.ntop.org/products/traffic-analysis/ntopng/) together with nFlow Probes (https://www.ntop.org/products/netflow-probes/nprobe/), or Solarwinds (https://www.solarwinds.com/netflow-traffic-analyzer).

These will provide you with the figures you need.

Please remember to take into account all the application servers you wish to load balance, and then add an additional amount for growths and peaks.