Ich bin ein SDNer!
I am an admirer of John Kennedy and I think he was a wonderful speaker, especially with gifted writers such as Ted Sorensen. Kennedy’s administration changed social culture in America. It ended the era of the fedora. The White House went from functionary to glamorous. America transitioned from the antiseptic 50s to the dynamic 60s. The country embraced big aspirations, from the moon to human rights. I included a picture of JFK stopping by a news stand from 1957. It was taken by the father of a family friend, six years before his famous speech in Berlin. I saw the picture again a few weeks ago at a show for the photographer in Boston and it made me wonder how many people were Berliners in 1957.
I was thinking about Kennedy’s speech this week because another week went by with conversation after conversation about SDN. The conversation has become so expansive, I am certain we are all having a discussion about different subjects under the guise of SDN.
My first observation is I keep hearing about separating the control plane from data plane and running apps in the network. How is that really helpful? Seriously, I just asked the question. I think it is the question that people do not want to ask because it is a universally accepted that separation is a powerful concept and they fear if they ask the question they will be perceived as stupid. I am not sure how powerful is powerful. Are we talking about matter and anti-matter or separating the saucer section, but people do think this separation stuff is really powerful. When you ask people to cite examples of the powerfulness of separating the control and data planes, the conversation goes sideways. The usual response is something about firewalls and email prioritization and load balancing.
The first question I like to ask is: what are the apps are we talking about? Are we talking about applications that use the network or are we talking about services in the network. That is an important distinction to make in my mind. 99% (or more) of networking people think services found in the network mean applications. Network services are things people most talk about when it comes to the SDN space such as: firewalls, load balancers, IPS, VRF, QoS, tracing, routing, etc.
When I think about applications, I think about applications that are used by people to be productive. That would be the GDP link to SDN. Applications require compute and storage. Applications access data via server to server or user to server. That is how I think about applications (i.e. software) defining the network. That is very different than how most people want to think about SDN. Most people want to take what is known and that which is comfortable and call it SDN. Maybe that is SDN 1.0 and the next version of SDN is really Application Defined Networking (ADN) and that is a point where we start to get a productivity gain from the network. Applications defining the construct, enabling the orchestrating and configuration of the network; that is a powerful concept.
Here is another way I think about it. If you can buy a load balancer or firewall or run IPS and VRF in the network today, why do those functions need to be implemented differently to run in a controller architecture (i.e. SDN)? If you can use QoS today, why do we need another method to give email traffic a priority over video traffic? When I hear people tell me about running apps in the network I ask why? What problem is being solved? What is being made easier? It seems a lot of people are embracing SDN and they are missing the point.
The point of SDN is to let the applications define the network requirements. That means an application architect or a network architect defines a set of needs and requirements that the application or a group of applications need from the network. A controller then tells the network about these needs and the network is orchestrated to meet the requirements of the application. That is a software defined network, or application defined network. The software is not in the network; the software uses and thus defines the network. Orchestrating the network to enable a firewall or tracer or load balancer is not helping the users of the network; it is helping the network administrator. At times the SDN discussion seems to be a closed circle of networking people implementing things for networking people. This point was driven home to me on a sales call recently in which the customer had PCI compliant credit transactions that he secured and prioritized by configuring the network devices through standard processes (i.e. CLI). After explaining the idea of Affinity, he finally said “you mean I can define all these relationships and characteristics from high level interface and push button and it will be implemented in the network?” The system engineer with me responded “yes.” The customer then said, “wow that would be big.” Yes, it would be big. I am into big.
A couple of closing thoughts and the first is a thank you from me to all the readers of this small outpost for my writing. Numerous times this year I received emails or Linkedin requests from people stating that they read my blog and would like to connect and network; thank you. I am a bit humbled that so many people read this blog. The outreach has even led to numerous presentation requests. I am getting out the road in the first half of 2013 will be taking the idea of applications defining the network to the people. Well, at least I will be taking it to gatherings of networking people. I will be thinking big in 2013 and challenging the status quo. It pales in comparison to JFK, but I hope to make a difference in the coming year. I leave you with words from JFK:
“We dare not forget today that we are the heirs of that first revolution. Let the word go forth from this time and place, to friend and foe alike, that the torch has been passed to a new generation of Americans – born in this century, tempered by war, disciplined by a hard and bitter peace, proud of our ancient heritage – and unwilling to witness or permit the slow undoing of those human rights to which this nation has always been committed, and to which we are committed today at home and around the world. Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe to assure the survival and the success of liberty…so let us begin anew – remembering on both sides that civility is not a sign of weakness, and sincerity is always subject to proof. Let us never negotiate out of fear. But let us never fear to negotiate. Let both sides explore what problems unite us instead of belaboring those problems which divide us…In your hands, my fellow citizens, more than mine, will rest the final success or failure of our course. Since this country was founded, each generation of Americans has been summoned to give testimony to its national loyalty. The graves of young Americans who answered the call to service surround the globe. Now the trumpet summons us again – not as a call to bear arms, though arms we need – not as a call to battle, though embattled we are – but a call to bear the burden of a long twilight struggle, year in and year out, ‘rejoicing in hope, patient in tribulation’ – a struggle against the common enemies of man: tyranny, poverty, disease and war itself…and so, my fellow Americans: ask not what your country can do for you – ask what you can do for your country. My fellow citizens of the world: ask not what America will do for you, but what together we can do for the freedom of man.”