Software Defined Networking (SDN) is the new way of designing networking solutions. SDN is not a networking standard (although there are SDN standards), but rather a philosophy in architecting new networks. Historically, the control mechanisms of the networking gear and the traffic flowing through that gear have been all intertwined, usually in the form of custom silicon chips that powered the hardware. The networking stack that processes the IP packets and the control mechanisms were all part of the same inter-dependent architecture. However, SDN, like your math professor from college correcting your paper, is teaching you a better way. The concept of SDN on the surface is fairly straightforward – let’s separate the data plane (which does the actual packet processing in the network) from the control plane (which manages and dictates the functions of the data plane). However, the implications of SDN on the industry will be fundamental.
This architectural segregation of the two planes, i.e. the heavy lifting of the packet processing and the brains of the network, has two immediate consequences: first and foremost, because of the clean separation of the intelligence of the network, from the packet processing, that intelligence can now be controlled remotely, centrally and most importantly, cost effectively for networks. This is critical for the enterprise IT manager, who can now visualize, design and push custom network features onto his/her hardware without doing any physical re-wiring, or any physical hardware replacements for new networking features. This is huge and has been one of the primary motivations behind SDN. The second immediate consequence of SDN is that there is no longer a dependency on custom silicon chips and therefore networking can be accomplished with X86-based standard hardware. This enables cost-effective networking gear, as the core of the value moves to the networking software. When giants like Google, Facebook and many others stop purchasing custom silicon-based networking gear and start building their own on X86 based hardware, there is no turning back.
Probably most readers are not old enough to remember the single-game handhelds from the 80s, but in a way, the networking industry is moving from that type of a custom hardware based era, to a software driven (app store) era. Today, to acquire a new game you only need to install an app on the same hardware, as opposed to how it used to be in the 80s where you needed to purchase new hardware just for adding a new game. SDN will provide a similar framework for networking professionals. Your networking gear will provide you the capability of software-defined networking, whereby new functions and features can be pushed and managed onto the same hardware without physically replacing the device. These software-defined features that can be packaged and implemented on the hardware are called NFV or Network Function Virtualization. We will investigate NFV in a bit more depth next week. We also previously discussed Software-Defined WAN here.
There is no question, Software-Defined Networking is the right way of designing, managing and upgrading networks and as software did to many other industries, software once again will change things around for the better.
Cahit Akin, CEO, Mushroom Networks, Inc.