Pass Dynamic Custom Parameters to Embedded Web Resource or IFRAME

I have a requirement to pass information from a related entity into an IFrame or web resource. 

I have read the link below:

https://msdn.microsoft.com/en-us/library/gg327945.aspx

But it explains how to do it with static parameters; I need to do it with dynamic values. How do I change the source of the web resource and then read the data in the target page? Is the web resource the best solution here or an IFrame?

Thanks,

Nathan