The ARPANET changed computing forever by proving that computers of wildly different manufacture could be connected using standardized protocols. In my post on the historical significance of the ARPANET, I mentioned a few of those protocols, but didn’t describe them in any detail. So I wanted to take a closer look at them. I also wanted to see how much of the design of those early protocols survives in the protocols we use today. The ARPANET protocols were, like our modern internet protocols, org...