/Why SD-WAN?


Over the last few years, we hear more and more the term “SD-WAN” (Software-defined Wide-Area Networking). When we speak to customers we usually get the following question:  What are the differences when compared to traditional WAN links?

When I think of traditional WAN links, I think of connecting users or branch offices to the applications hosted in the data center. The network manager picks the phone, calls your ISP or MSP, and requests a dedicated MPLS circuit and (if you want to have redundancy) a backup link which can be a secondary MPLS link or a simple Internet connection running VPN IPSec. Since you start conversations with your ISP until you get the service up and running (raise the PO,  few weeks for approvals, provisioning, etc.) it can take between 45 and 90 days.

However, in the era of Cloud services, the way we communicate has changed. Nowadays applications are spread across multiple clouds, and users consume those applications on a variety of mobile devices. This turns into higher demands of bandwidth and brings some challenges, like network capacity, security, and the ability to quickly make changes in a rapidly growing environment.

Do you remember the last time you had to plan a WAN change? Few weeks of negotiating with other business areas to avoid any impact in the service, CAB meetings, maintenance windows, rollback plans,…in summary, a time-consuming effort.

And what about keeping the same architecture in this new era? Will you keep routing your branches through your main data center before forwarding it to the cloud? That will be the first option if your manager says “We want to keep end-to-end (E2E) control”. The problem is that you will end up with latency, bottlenecks, additional hops,… but hey! at least you have E2E control and it’s secure!

Should we talk about SLAs? Hmmm…that’s another battle you need to pick.

How can SD-WAN help us?

SD-WAN brings new ways of simplifying the traditional WAN landscape. Some of the benefits of adopting this new technology:

  •  You get better usage of your existing links by aggregating bandwidth and providing dynamic load-balancing
  • Optimal delivery path across the entire network.
  • Reduce WAN costs by using internet and LTE/5G connectivity as an alternative to MPLS.
  • Centralize management through a single pane of glass.

What are the use- cases?

1.- Deploy multiple links

Many branch offices cannot afford having multiple links due to costs. This means that if you require bandwidth and low latency access for your critical applications, you will probably be impacted by performance and congestion. However, what if we could aggregate any existing link that you may have and apply network policies based on the criticality of your applications? I know, every service owner will say that their apps are the most critical ones, but that’s a different fight.

SD-WAN will allow you to dynamically steer traffic based on the needs of your business.

2.- Simplify and Accelerate Deployments

In a world where agility and time-to-market are key for the business, having a solution that can help provisioning configuration to any new endpoint will make your life easier. Said that you still need Eyes & Hands to run the initial setup. Someone in the field will have to connect all the different components and ensure there is connectivity. The easiest way is to send a HowTo guide with clear instructions of the setup and provide a script for the initial configuration. Once the device is activated, we can remotely push the configuration, monitor, and troubleshoot.

3.- Global Managed WAN

If you’ve been in global projects, you might have seen challenges around using the approved service provider around the world (I still remember the problems of connecting the last mile in countries like Romania, Morocco, and Croatia). Usually, the result of this is higher costs in your project as your main provider needs to partner with some local or smaller carriers.  With SD-WAN you now have a centralized orchestration tool that allows you connecting sites with each other regardless of the type of circuit/connectivity they have. You will simplify the deployment timelines and save some headaches. If I had this ten years ago, I wouldn’t probably have spent months in countries dealing with interconnectivity and new WAN deployments.

4.- Security

Now that everything is cloud-connected, security becomes even more important than before. A question that may arise is: How do we enforce policies and ensure all our branch offices have standard configurations? How do we apply new changes on a global scale?   All these concerns are now solved with SD-WAN. One thing to highlight, your solution will provide a log and event aggregator of all your WAN connections,  making security management easier. Last but not least, if you end up with a solution that applies ML/AI to monitor configurations and ensures policies are standardized along the branch offices, you may be able to remove some of your routine tasks and focus on more challenging activities.

What are the top solutions in the market?

We are seeing more and more SD-WAN solutions in the market, however, for the sake of our post we will highlight the following ones:

  • Viptela (acquired by Cisco in August 2017) is Cisco’s cloud-first architecture for the WAN. It’s integrated with Cisco’s Digital Network Architecture (Cisco DNA) platform.
  • Velocloud (acquired by VMware in December 2017) is integrated with VMware’s network virtualization platform – VMware NSX.
  • Talari (acquired by Oracle in November 2018) is a complement of Oracle Communications’ Session Border Controller (SBC). Large telco carriers use SBC with Talari to provide QoS over WAN links.

In the following posts, we will disclose some of these solutions and how they can help you in your business.

Have fun! Stay safe!