SDN, NFV and Network Automation

In my previous blog, I explained the basics of Software Defined Networking (SDN), how SDN has evolved to this point, the separation between the control plane and data plane, plus we named the three main flavors of SDN: Open SDN, SDN by APIs and SDN via overlays. We also covered the principles of the first approach, Open SDN. In this blog, I will cover the implementation of this technology via APIs, a preferred method used by traditional networking hardware companies. SDN implementation via APIs refers to southbound APIs that configure and program the control plane active on the device. There are a number of legacy network device APIs in use that offer different degrees of control (SNMP, CLO, TL1, RADIUS, TR-069, etc.) and a number of newer ones (NETCONF/YANG, REST, XMPP, BGP-LS, etc.) that offer different degrees of control over the network devices, data plane, topology, etc., each having different advantages and disadvantages. I won’t cover them in depth...

The joke goes around that the true meaning of SDN is Still Don't Know, there are different definitions, depending on who you ask, and three different kind of approach to SDN (SDN by overlays, SDN by APIs and Open SDN). As for the former, everyone agrees that SDN is a network paradigm that separates the control plane from the data plane, the differences are on the approach, protocols and semantics. As if that wasn't confusing enough, we also have multiple SDN controllers, some open source some proprietary but there is nowhere to be found a one to one comparison for features, pros and cons... but which one is which and whose are relevant and active in 2017. I will try to clarify some of these questions: Some closing thoughs:  OpenDaylight continues to show momentum OPNFV – embedded (so is ONOS, OpenContrail) Over 600 developers supporting and contributing Increasing number of customer deployments worldwide (AT&T, KT, Tencent, etc) Mostly datacenter-centric ...