The Internet: If A Wants to Talk to B, Why Does C Need to Be Involved?

Suppose I have two smart devices called A and B sitting next to each other on my desk. Both A and B know how to find C, C knows about both A and B, and C can bring everybody together. Firewalls, network address translation (NAT), carrier networks, and other realities of the modern internet can sometimes get in the way. Meanwhile, the devices sitting in our pockets, on our desks, in our homes, in our factories, and at the edge of our networks have become vastly more capable. perhaps the first question should be, “Does A actually need C to talk to B in the first place?”