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The June seventh Telarus Tuesday call featured Tyler Smith, Telarus VP of engineering. Tyler dives deeper into SDN, Software Defined Networking and shares a few case studies. The entire call recording can be watched here.

How to Define Real Software Defined Networking Solutions

Just one year ago at the annual Interop Expo, Software Defined Networking was barely discussed or promoted. Fast forward one year, and the 2016 expo had mentions of SDN in nearly every session and presentation. The SDN term has picked up momentum and is almost a marketing term thrown around like Cloud or UC.. Just like the term cloud is loosely defined, SDN has likewise started sharing the same unfortunate clarity.

When we talk about SDN or SD-WAN, there are a few minimum requirements to really qualify for the term.

  • It is a network service or an overlay that is going to replace what is a more traditional type wan service like an MPLS service. Meaning a private network provided to a person from a networking provider.
  • This solution is provisioned and you interact with it in some sort of portal or maybe even cloud driven.
  • Automatic failover. If you plug in two connections, it needs to fail-over to the other.

With these three common denominators to define SDN, you can wash out all of those tricky claims many people are making about their “SDN solutions” and focus on the real solutions.  It’s a hot and trendy term, so following this definition will save you a lot of frustration of wasting time with solution offers that are somewhat counterfeit or misleading.

Key SD-WAN Features

The providers that are offering legitimate SDN solutions are able to provide a key feature as it relates to performance. For example, let’s examine a scenario where you have your two internet connections. There is an application like hosted VoIP and a low-cost bandwidth solution like cable backed up with a DSL connection. Neither of those connections are bulletproof. A key feature functionality is the ability to adapt to performance of the environment in real-time. Look at latency with the cable and DSL along with jitter and packet loss as all three affect the voice quality. Good SDN solutions will be able to take those into account in real time and adapt a voice call as it relates to the real time performance of the network. When problematic connections arise, it could reroute to the secondary link without disrupting the call. All that is done without having to touch the box since it’s automated.

In a traditional router environment, you can load balance two connections as well as an automatic failover. But typically you will do that based upon hard downs. That will require manual swapping and restarting connections which cause interruptions. SD-WAN does all that without any perceived disruptions or manual servicing.

A bonus feature is the ability to alert. Set notifications to alert about an outage and gain visibility on who is doing what within your network environment.

Current SDN Carriers

This is an evolving space, and while there are a lot of providers coming out with great SDN solutions, this is a list of who is currently available:


They are network agnostic. Their solution is an overlay on top of bandwidth. The deal will have determined where to get the bandwidth, how much will be used, and then Freewire’s solution will be an overlay on top of that. It can be an MPLS replacement and have applications like voice perform cleanly even over an internet-type connection. They are transparent about using backend solutions from VeloCloud.

Vonage Business

They have great interest in having their application work properly across different types of connections. They have gone down the road of talking about SDN as it relates to voice. Vonage also uses VeloCloud. Vonage recently noted their trouble tickets have been significantly reduced since the deployment of their SDN solutions and they couldn’t be happier about it.

BigLeaf Networks

BigLeaf is a homegrown application and they have their own offering. They have strategically positioned themselves to go after customers that want to retain their own firewalls. There are plenty of customers in this space that are required to retain their firewalls, so BigLeaf does a great job at offering a solution for them.

Where is SDN a Good Solution?

Case Study #1

In this example, the customer has the following description:

  • Retail Store Chain
  • Hundreds of branches
  • Hosted VoIP customer
  • Private cloud (everything remote to branch)
  • Dual provider MPLS T-1 based WAN (failover)

The problems this customer faces are:

  • Bandwidth starvation
  • New applications
  • Remain PCI compliant
  • Retain similar cost structure

In the T-1 world, the only real other option is to add another T-1 which may be around $250/month extra. Now taking a look at the alternative, let’s say you grab a fiber connection with 100 megs. You have the opportunity to get some lower cost bandwidth. Then you back it up with a 25 meg 4G solution and have the 100 meg SDN overlay.  They’ll have the new ability to run their new applications and even save a little bit of money.

Case Study #2

In this example, Telarus offers its experience with switching to SDN. Our situation was as such:

  • Technology Company
  • 70 employees
  • Hosted VoIP customer
  • Fairly heavy SaaS users for production platforms
  • Office 365 customer
  • Few internal servers hosting applications

The hosted VoIP solution is key to our environment. We had a 100 meg coax and a 100 meg fiber connection with fiber being primary. With testing the SDN solution, we experienced a bunch of outages lasting about an hour or two each. For most employees, no one even knew about those outages since the automatic failover kicked in. With doing the math, an hour of downtime for us is about $3,500/month. Within 8 or so business days, there were about eight of those outages which would have been about $20,000 lost based on productivity. So the auto failover is a key piece. The reduced down time will result in the service paying for itself over the period of a year had the SDN not been in place and those outages taking their toll.

VXSuite Validation

We have a probe that goes out and VXSuite validates performance. A recent announcement revealed that two probes on opposite ends of the continental US are available for our free circuit monitoring on Telarus sourced circuits. This monitoring acts as a third party validation of the network performance in an SDN environment. Telarus has been monitoring our own calls and has been able to validate all of the performance factors across the multiple touch points in our network solution.

IT professionals everywhere are really starting to take interest in the SD-WAN space. The hope being two fold: replace an expensive MPLS with something less expensive and also the performance side.

Be aware, if you are not having the SDN conversation with your customers, some else will. So make sure you are asking the right questions!