Hello,
I have looked into the RTSP standard, and it looks like the default ports are 554 for TCP and UDP. Since it looks like your cameras are using a different port, you may want to try creating a custom service for 8016 externally, since the default rule is currently translating 554 to 8016. Of course you can also try connecting to the cameras with the public IP and port number 554, that should work with your current setup.
However if you are unable to change the port your client software uses, definitely try creating a custom service for 8016. You may also want to double check that the camera has the RV set as it's default gateway.
Hope that helps,
Christopher Ebert - Advanced Network Support Engineer
Cisco Small Business Support Center
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