As I was learning Neutron networking and started to present my experiences to audiences, I coined a phrase that I continue to stand by: Networking is hard. Networking is the most complex component in OpenStack and for good reason. This is because networking is a complex part of computing. It takes time and hard work to understand networking. It's often left to the network administrators and neglected by others. Hats off to you network administrators. I spent seven years of my professional career avoiding learning some of the core concepts of networking and leaving it to the folks that did networking. OpenStack is where it caught up with me and bowled me over. To administer an OpenStack cloud that uses Neutron networking, you have to understand some of the core concepts used in networking. As we work through the rest of this book, I'll make sure to explain these concepts as we come across them so that if you're not a networking guru, you will hopefully come out on the...