DevOps in the Enterprise

The role of IT in DevOps

SDN or Software Defined Networking – Intro to What, Why, How

Software Defined This, Software Defined That. We live in a time where our world is largely defined by software. At least in the so called developed world. Software’s everywhere. There’s obvious places like apps on our Smartphones or the PC or MacBook and there are (way more) hidden ones. Hidden to most people that are not intimately involved in building the software or running the infrastructure for all the solutions.

Software Defined Networking or SDN for short abstracts low level network functionality and enables the creation, operation, and control of a flexible network infrastructure across entities requiring or providing network connectivity.

OK, I made up this definition assuming it is general enough to get the idea. There’s plenty of very good definitions of what SDN is and does. Here’s a few:

Microsoft says: “Network without limits for your datacenter without boundaries – Enable application/workload-centric network infrastructure with flexible application mobility across datacenters and clouds. Centralize control of network infrastructure and operations across virtual and physical. Maximize operational efficiency with automated network configuration and management.”

Wikipedia starts its definition of SDN with: “Software-defined networking (SDN) is an approach to computer networking that allows network administrators to manage network services through abstraction of lower level functionality. This is done by decoupling the system that makes decisions about where traffic is sent (the control plane) from the underlying systems that forward traffic to the selected destination (the data plane). The inventors and vendors of these systems claim that this simplifies networking.”

SDN Central’s website states: “Software Defined Networking (SDN) is a new approach to designing, building and managing networks. The basic concept is that SDN separates the network’s control (brains) and forwarding (muscle) planes to make it easier to optimize each.”

If you are interested in learning in more detail about SDN and Microsoft you can start with the website I borrowed above definition from and follow the links or you can read a very good summary of SDN my team mate @SymonPerriman wrote for ComputerWeek’s Network Computing. Based on Microsoft own SDN Symon walks the reader through the intricacies of Software Defined Networking.

Real-World SDN, Lesson 1: Management Up Front
Advice about setting realistic goals and focusing on management

Real-World SDN, Lesson 2: Conquer The Enemy Within
About the internal struggles organizations often face when getting started with Software Defined Networking

Real-World SDN, Lesson 3: Focus On The App
Why the applications running on the network should take center stage

Real-World SDN, Lesson 4: Plan For Hybrid Cloud
Why to include support for hybrid cloud, even though you might not need it now

Along the way you will get a biology lesson too. Learn what a “Bowerbird Admin” is and discover a new specifies of spiders. You will cross paths with a Zombie snail and in the first installment of the series learn everything about what a network has in common with a siphonophorae.


There’s a great free online Coursera course on SDNfrom Georgia Tech.

Have fun.