To be able to research on why you are getting 403 errors with multiple request, it would be best if you open a support ticket at:
https://www.wowza.com/support/open-ticket for Wowza's Support Team to further investigate.
Please attached bellow logs to your new case:
If you are not sure how to get this information please see the following tutorial.
We don't apply any DOS protection in that way. I would suggest that you
open a support ticket as suggested by Jason so we can investigate this in more detail. Please include the steps needed to reproduce.