A few years back I worked for a regional Internet service provider in the northeast US. One day a guy who did finance and regulatory work for us asked me how many of our customer point to point links with A and Z locations in different states were either dedicated to voice traffic or carried more than x percent voice traffic.
After asking a few thought provoking questions like if the percentage was based on traffic measurements or link capacity and how we would make that calculation on a circuit with asymmetrical speeds, I explained that it would be nearly impossible for us to tell unless the customer declared it to us.
He then told me that there was some new federal tax on interstate circuits carrying voice traffic and that if we couldn’t tell if a customer circuit was carrying voice traffic or not, that we would just need to start charging them all the tax no matter what. It might even apply to regular Internet services where the edge router and customer site were in different states.
And that is the story of how the ISP that I worked for added yet another fee to all of its customers.