Hi Micky,
interesting. Can you also attach page 6?
And it means: the target system is actually outside of your corporate network, so you need to communicate through your firewall. -- That adds an extra level of complexity... 
In that case WebSockets would be an option, if the target system supports it. You may also want to ask your Unibox contact about this. (Otherwise a Business Connector installed in the DMZ of your network might indeed be your only option.)
Best Regards, Ulrich