Instead you have to link the MAC address of devices to specific IP addresses. One of those would be MAC-Layer security that would not allow just anything to be connected. If an organization has implemented more specialized firewalls I would also expect they may have employed additional security measures. I'm just trying to understand how specialized that firewall unit is. Is this 'firewall' a specialized device (dedicated as a firewall) or is it merely a standard router with a WAN port and multiple LAN ports?
Have you tried pinging the IP address of the ATEM from your laptop? you are connecting a USB cable from your Laptop to your ATEM and then running the ATEM Setup Utility to configure the IP address. I think we've all been assuming you are in fact setting the ATEM's IP address by the usual (and only) method to do that. You are now connecting both your laptop and the ATEM to your 'firewall'?ĮDIT: And (as per tom below).
It just brings up a 'red flag' to me that something may still be odd about how you are trying to configure things. No sure if that is simply a Typo - as the ATEM has no place for you to configure a DNS (it doesn't need this). The only odd thing I notice is that you list DNS for the ATEM. that's entirely different to what you had before.