Yes, you can follow this guide for tuning the servers:
How to do performance tuning
And you can utilize this Load Test Tool:
How to get Flash RTMP Load Test Tool
With a 1g nic (20% overhead accounted for.) = 800mbs throughput, which is 800 1 mbs streams, or 1600 500kbs streams.
You can use this formula for calculating:
You will have to test your actual server/network using the load test tool, or monitoring utilization in production. You must be properly tuned. And to achieve maximum levels you may have to tune your server and network in other ways outside Wowza.
number of users * stream bitrate + 20% IP overhead = total server bandwidth
I hope this is helpful.