Once upon a time, there were networks and network engineers, but programmers came and took over the field… actually, I am just kidding. Networks and network engineers still exist and they will never go away, however, they are definitely not going to be the same. I remember that terminologies such as Software Defined Networking (SDN), OpenFlow, and OpenDaylight started to pop up around my work environment in late 2013 and even though initially there were just these 3 terminologies, they did bring a lot of confusion to classic network engineers (even today that is still the case for many). The concept of SDN is a lot more mature today and has brought many other terminologies (just when you thought it could not get anymore confusing) into the mix: Cisco Application Centric Infrastructure (ACI), Cisco Digital Network Architecture (DNA), Cisco Network Services Orchestrator (NSO), Cisco Intelligent WAN (iWAN), and Software Defined WAN (SD-WAN) to name a few. Network Function Virtualization (NFV) and VMware NSX are other terminologies that popped up around the same time, but are actually something different. I want to briefly break down these terminologies and give you some concepts to help you understand the differences and prepare you for another blog entry that will solely focus on the technical details of NSO.