I spent 2 years writing multicast routing algorithm implementations for an overlay multicast startup I cofounded. The moral equivalents of PIM sparse and OSPF. I wouldn&#x27;t do it this way again, knowing what I know now, but we did LSA forwarding between nodes the same way a Cisco would flood LSAs over a set of unruly PPP DS1 links. The hard way, is what I&#x27;m trying to convey here.<p>Anyways, I interviewed a company my friend Nate was working for, on a lark (my company was sort of winding down).<p>First question I got: &quot;explain Bellman-Ford routing&quot;. Bellman-Ford is one of the simplest distributed systems algorithms there is, and certainly the simplest foundation for a routing protocol (it&#x27;s what the RIP protocol does). I had, prior to that interview, implemented RIP <i>twice</i>, in two different jobs.<p>I totally bombed the interview! My mind just went blank. I could explain how link-state routing with shortest path graph reductions worked, but not how a much simpler algorithm worked.<p>The interview made some clucking noises about how <i>interesting</i> it was to be interviewing someone who wasn&#x27;t a Stanford CS student.<p>The next interview asked me to implement Towers of Hanoi non-recursively. I refused.<p>Obviously, I didn&#x27;t get an offer.