SDN Is The Vehicle, Not The Destination


I recently booked a flight to San Francisco for an IT conference I’m attending. Flying, by itself, is not especially exciting to me. That’s not to say that as a consumer of traveling services, I find nothing about travel or airplanes interesting. For example, I am interested in the cost of a trip. I’m interested in logistics as I find myself endlessly fascinated by how I get routed from hub to hub to get to my final destination. I like to know what I should do in case of an in-flight emergency. But those aspects of travel are not personal goals or aspirations, however interesting they might be. My goal is to get to San Francisco.

I see parallels with software defined networking. SDN is all the rage these days. Marketing teams use “SDN” to describe aspects of their products. Vendors co-opt “SDN” to reflect their corporate views. Network engineers read about SDN and ponder what it means for their futures. Pundits prognosticate a plethora of predictions about SDN products. While I’m as guilty as any, I think that this is a type of myopia.


You see, we’re all fascinated by the airplane.

SDN is that airplane. And as interesting as airplanes are, what’s really interesting is where the plane is taking us. SDN is an enabling technology.  SDN is the foundation upon which rich, compelling, and new networking services can be built. Yes, we still need to have a focus on the plane for a while. We don’t all agree on how the plane should work. We think there might be room for a few different kinds of planes. And perhaps buses, trains, and cars haven’t quite outlived their usefulness. Surely, the airplane must be built, but as we’re building it, we need to keep in mind that SDN’s ultimate purpose is to take networking somewhere.

In that sense, SDN isn’t the big story. The big story is that networking is moving forward. In that progress, we can see that we’re heading to an interesting destination. Automated provisioning of tightly integrated IT services. That’s interesting. Heretofore unthought of or impossible network applications. That’s interesting. The ability to implement business policy up and down the IT stack. That’s interesting, too. Those are the sorts of things that I’m really excited about, even if I am pondering airplane engineering in the form of Python, promise theory, Ansible, the OpenDaylight project, overlays, OpenFlow, and the like. But getting to San Francisco is what I’m looking forward to the most.

By Ethan Banks

Ethan Banks is a podcaster and writer with a BSCS and 20+ years in enterprise IT. He's operated data centers with a special focus on infrastructure — especially networking. He's been a CNE, MCSE, CEH, CCNA, CCNP, CCSP, and CCIE R&S #20655. He's the co-founder of Packet Pushers Interactive, LLC where he creates content for humans in the hot aisle.