What is SD-WAN and How Can I Use It?

Teneo has established an SD-WAN practice to fully explore all things SD-WAN and help you navigate your way through the fast-changing SD-WAN market landscape. We’ll help you to answer questions such as, “What is SD-WAN?” and “How can I make use of it in my global WAN architecture?” but first let’s be clear on what benefits SD-WAN can bring.

What Benefits Can SD-WAN Bring?

SD-WAN (short for Software-Defined Wide Area Networking) is set to change the way networks of the future are architected and is already beginning to take global WANs by storm, allowing network teams to:

  • Centralise and scale operations
  • Increase network agility
  • Address security challenges; and
  • Reduce costs.

What’s Driving the Need to Cut WAN Costs and Complexity?

New Services and Applications

Over the last 5 years we’ve seen a rapid evolution in the type of new services and applications being introduced onto the network. We’ve well and truly entered the digital and cloud-first era and enterprise architecture considerations have had to move up a few gears – along with the demand for more bandwidth. However, whilst an organisation’s applications might be shiny and new, we’ve observed that the WAN is often the last thing to be considered for an upgrade in a business’s quest for innovation. And so predictably, the WAN’s rails end up starting to creak and falter, leaving us with something that resembles the mine cart chase scene in Indiana Jones and the Temple of Doom, where the cart is the application and the rails are the network.

New Working Models

Added to that, working models are more flexible than ever before, meaning the end user and the applications they consume are rarely housed in the same building. The further application data has to travel across a WAN, the more likely you are to see performance problems. From a consumer perspective, the always-on interaction with digital devices, including the consumption of voice and video, now blurs the lines between personal and professional application usage. Due to this, time has become more precious than ever before, meaning an end user’s expectation of application speed and response time is at its highest level yet and is only set to rise.

Shift to a Hybrid WAN

So what’s the cost to get the network back on track? With IT budgets often being squeezed it can be tough to stay creative enough to avoid the typically high capital costs of a traditional enterprise WAN. Once you’ve factored in the cost of networking equipment refresh and been presented with yet another rigid set of connectivity options, for example MPLS (multiprotocol label switching), from a limited number of suppliers per region at contract renewal, it can feel like you don’t have much financial leverage at all. Whilst broadband Internet is relatively inexpensive (normally 20-100 times less expensive than MPLS), with the Internet come reliability and security challenges when used in a corporate environment. The ideal scenario would be to leverage both of these options together along with private line connections and others and operate a hybrid WAN. But that level of complexity has to be designed, configured and managed by someone…

The Global Network Team

The roles in the global network team have also changed. No longer does a network management role sit strictly in the area of the network, neatly boxed off with clear boundaries. Individuals within these teams are now expected to be generalists rather than specialists, with increased knowledge and experience required in the domains of security, storage and application performance. The network manager has become the collaborator and sits central to any new major IT project, now more so than ever before and this is critical. With today’s nature of business being 24×7, global network teams are frequently expected to manage at least half of the world’s business from one single location. Already with a smaller team due to the generalist nature of individual roles, when half of that team is constantly on a plane travelling to the next branch office that needs equipment to be fixed or installed on the other side of the world, colleagues really start to feel the pressure. The network team really can’t be everywhere and do everything at once. Or can it?

Enter the Architectural Concept of SD-WAN

So What Exactly is SD-WAN?SD-WAN

SD-WAN leverages technology to make use of all hybrid connections you have available on the WAN at any one time, constantly monitoring them to automatically choose the best possible path available for the type of traffic that’s crossing your network and the business priorities you set. Those connections can include your redundant – but very expensive – backup lines. You’ve already paid for them so why not use them? And then there’s broadband Internet, which you can now start to leverage at a more cost effective rate than MPLS. This approach makes your network much more flexible, allowing it to live and breathe, reacting to network conditions in real time without the intervention of a network team member. Imagine your hybrid connections are like the strips that make up a string cheese and your SD-WAN the whole, much more robust product.

The number of SD-WAN offerings available continues to grow since everyone who’s anyone in the networking space is projecting the same vision of the network of the future. But how each SD-WAN product or service works can differ. Fundamentally, each offering is made up of a control plane and a data plane.

The Control Plane

The control plane (or controller) is the GUI (graphical user interface) through which the network team can centrally design, configure and manage WAN traffic based on business-related application policies. This typically resembles a network topology map. The controller is usually software running either in the cloud or on an on premise machine and essentially does all the hard work for you.

In most cases, the controller will also allow zero-touch provisioning, where, providing someone is onsite to perform the simple task of plugging in a branch edge device, removes the need for a network team member to travel to remote sites to set up new equipment – saving valuable time and money.

The Data Plane

The data plane consists of all WAN branch edge devices that handle network traffic and are deployed to each branch site. Once plugged in, a branch edge device will establish logical connections with other edge devices on the WAN and download the configurations it needs to operate. These logical connections not only allow for efficient and dynamic load sharing of traffic but also serve to create encrypted paths across multiple WAN connections and carriers, such as hybrid Internet and MPLS, therefore addressing any security level inconsistencies.

SD-WAN technology deployed at the branch can also serve to consolidate other branch equipment such as routers, next-generation firewalls and WAN optimisation devices, which can all run as virtual instances on the same hardware or software and be kept up to date through the same controller with minimal intervention.

What SD-WAN Options Does Teneo Advise?

Because this market space is changing so rapidly, we’d strongly advise that you run a pilot project in your environment before making a decision on your preferred SD-WAN technology. To enable early adoption of SD-WAN technology, all of our SD-WAN offerings are available as a managed service, each designed for different levels of scalability taking into account your existing network landscape.

So we can help you to determine the right approach for your global WAN, we recommend you ask yourself the following questions:

New Services and Applications

  • What new services or applications are we deploying for employees and for our customers that are going to increase bandwidth needs, e.g. voice, video, telepresence, VDI, ERP?
  • What traffic do we prioritise today?
  • When did our WAN last go through any kind of upgrade?
    • What advantages or disadvantages does our WAN provide?
  • What investment have we already made in WAN optimisation or QoS technologies?
  • How else is the business looking to increase productivity?

New Working Models

  • How many remote workers do we support?
  • How many guest workers do we typically have accessing our network?
  • How many branch offices do we have on our global WAN?
    • Where are they?
    • How many employees are based at each?
  • What use of public cloud services are we seeking to make to enhance traffic management or application availability?
    • How do we expect this usage to increase in future?
  • How many network outages are we experiencing that are either forcing locations to close or impacting productivity in multiple locations?
  • Where are we planning on opening new global office locations?
    • Where will that process need to be especially quick?
    • How long does it normally take us to implement new network services?

Shift to a Hybrid WAN

  • Who are our current WAN connectivity providers?
    • What costs do they charge globally?
    • When do our contracts end?
  • What increase are we planning for MPLS spend to accommodate bandwidth growth?
    • Is the cost prohibitive to us?
  • Are we looking for new MPLS providers or broadband Internet options to augment MPLS?
  • Are we seeking ways to better understand business-class carrier service performance vs cost at a global level?
  • What compliances do we have to adhere to from a security perspective?

The Global Network Team

  • How many colleagues are there in our global network team?
    • How are responsibilities split?
    • How is each person’s time divided by those responsibilities?
    • Is that enough?
  • What monitoring capabilities do we have to risk-assess WAN performance on a global scale, 24×7?
  • How are we currently managing the equipment at our branch offices?
    • When are our refresh cycles?
    • Are we looking to remove any of that equipment altogether, e.g. routers, firewalls, storage?
  • Where else has the network team been asked to reduce cost, complexity and risk?
  • What else would I rather be spending my time doing instead of basic WAN management?

To explore the answers to these questions together, we offer an SD-WAN Lunch and Learn, held onsite with your network team at your offices at a date convenient to you. Find out more and register your interest.

You can also email us at to ask us an SD-WAN question or arrange an SD-WAN meeting at any time.