Skip to content

Month: March 2017

Network Automation vs Software Defined Network – Ansible vs Openflow

Published by castroflaviojr on March 16, 2017

At Verizon, we are moving towards automating network configuration and provisioning. To me the goals for this move can be summarized as:

  • Maintenance cost reduction
  • More agile deployment processes

Coming from an OpenFlow SDN background, where changes to the network can be immediate, and looking at the real world, where changes to the network require human approval and human intervention to be deployed resulting in 1-2 weeks time, it’s really hard to tolerate this acceptance for delay with legacy systems.

I’m much interested in identifying where automation of legacy systems offers a real benefit over OpenFlow networks and vice-versa. My experiences tell me the biggest paradigm shift comes from the users. If the network operator is used to the OpenFlow paradigm, and has the software development skills, pretty much anything can be done. On the other side when the network operator comes from a classical Cisco network engineer background, even incremental changes to the network as advocated by network automation gurus can be challenging.

So far, my only experience with network automation is Ansible. A great positive factor for Ansible is its learning curve. Very easy to try. Right now, I’m intrigued with testing of Ansible code, refactoring variables consists of project-wise find and replace, it’s also not yet intuitive to me how Ansible code can be continuously tested and deployed. Quoting Uncle Ben: “with great power comes great responsibility”, Ansible does give you the opportunity to mess up things really well.

That’s where my bias towards OpenFlow comes in: successful OF projects, like ONOS, have been tested for a couple years now and are quite mature for open source projects. AS mentioned in my last article, to me it all comes down to the skill set companies want to cherish, it’s easy to leverage network engineer expertise plus some python scripting capabilities to work on network automation, but I bet you won’t get great code quality out of that.

Another option is to leverage great software developing skills to make sure you do get the code quality, but then what I would advocate for is to get this great software developer and put him to work to develop a real SDN system with real software challenges in place where the opportunity for gain is incredible.

OpenFlow has an inherent disadvantage which is the requirement for extra hardware support. Successful OF deployment have been performed with new gear, or have used successful hybrid deployment strategies, which can be complex. So, if you want to improve current deployments, OpenFlow won’t be your pick.

I’m still skeptical regarding the value of network automation, other than incremental adoption of new technology, in other words, it’s easy to sell.

1 Comment

What’s going on?

Published by castroflaviojr on March 14, 2017

In January, I’ve started working for Verizon as a DevOps Engineer with focus in network engineering. I’ve been working with SDN for about 2 years and my last experience was at the Open Networking Lab, a research lab, pioneer in terms of SDN research, in collaboration with AT&T.

In this article, instead of describing a technology as I usually do in this blog, I’ll try to summarize my thoughts on where this industry is going.

Every day it’s clearer to me that innovation in service providers is driven by two factors: pressure to reduce acquisition and operational costs; increasing pressure to deliver new services fast, which BTW happens in order to generate new sources of revenue.

Most service providers are trying to leverage open hardware from OCP and open source technology in order to achieve those goals. The “open” alternative of solutions is quite cost-effective compared to current legacy solutions; at the same time it offers the opportunity to be at the edge of technology development, that’s to say open technologies fasten innovation cycles significantly. The disaggregation of network devices has played a tremendous role in enabling innovation as well.

There are challenges in order to achieve those goals. Acquisition costs are definitely the most compelling point of open technologies. The delivery of the open source solutions on the other side is where the risk lies. If you are used to open source, you do know that bugs are just part of your life. There’s a 9 in 10 chance that at least one of your critical features won’t be supported natively by available open source solutions.

To couple with that I believe service providers should invest in acquiring diverse talents, or invest in training its own staff.

The truth is change is inevitable, you either hop on the boat and deliver reduced costs or new services or you will be left behind. We’ve started to see evidence why that has been happening with big vendors, I believe this pattern will repeat with providers.

In the next posts, I’ll try to comment on what is going on with vendors or make a follow-up post with my thoughts on costs, risks and benefits of this search for innovation as well.

Leave a Comment