SD-WAN as a Service: A Cloud-Based Game Changer

Odds are, if you’re reading this, you’re either an IT decision maker or an IT specialist. Or, maybe you’re just really excited to learn more about software-defined networking. That’s cool, too. Software-defined networking (SDN) is a big industry buzz word right now, and for good reason. Linking SDN with wide area networking to form an SD-WAN offers a tempting and effective alternative to MPLS-only networking. If you or your employers are investigating your networking options, we’ve put together a comprehensive summary just for you. Below, we’ll explain SD-WAN, how to purchase it as a service, and why this model is an industry game-changer.

What is SD-WAN?

The main thing that distinguishes an SD-WAN network is the abstraction of the control plane.  This enables administrators to set traffic policies from a central location using software – hence the name, ‘software defined.’ This offers advantages over using standard MPLS networks which require a painstaking process of provisioning predetermined traffic routes. With SD-WAN, data can be switched between multiple paths on the fly depending on local network conditions and defined policies. This simplifies and speeds up network management.  All policy changes and updates can be applied in one place and then distributed to devices on the network.

What is SD-WAN as a Service?

Businesses have the option to either run their own SD-WAN, or they can purchase it as a managed service. Internally managed SD-WAN will use the standard internet to send packets from A to B.  SD-WAN as a service connects your business’ on-premise network to a provider’s cloud gateway. This is often connected directly to leading public cloud providers for smarter access to enterprise SaaS programs and services.

SD-WAN and Bandwidth Costs

Before we examine the benefits of using SD-WAN, let’s touch on one of SD-WAN’s key selling points – low costs. MPLS bandwidth costs are almost always higher than other forms of data transport.  Once a business is set up with an MPLS vendor, they are locked into those rates. If your business sends video, voice or other bandwidth hogging data via MPLS, it can get expensive. These high costs make scaling bandwidth over MPLS a frightening prospect router and/or circuit costs mount up quickly. With SD-WAN technology, the software automatically finds the most cost-effective routes and transport methods, mixing and matching as needed. This also applies when scaling up as this only means provisioning extra connections to increase bandwidth. Depending on the scenario, these connections could use xDSL, cable, LTE or even MPLS.

SD-WAN and Security

Another huge benefit of SD-WAN is the built-in encryption feature. MPLS usually offers better security than a standard internet connection, but it doesn’t include native encryption and is heavily dependent on the network being configured correctly in the first place. Encryption can, of course, be added to an MPLS network if you so choose. But with SD-WAN, data is always encrypted on one end and decrypted on the other, protecting users from sniffers and ‘man-in-the-middle’ attacks.

How SD-WAN as a Service Benefits Real-Time Apps

Now we come to the meat of this issue. How does SD-WAN as a service stack up against MPLS when providing access to real-time applications? One of the main reasons why businesses tend to hang onto their MPLS network is because they need to maintain real-time connectivity. Take your business, for example: do you use a VoIP telephone service or provide access to cloud-based applications such as Office 365 or Salesforce? If the answer is yes, then you’ll know that providing these services over the internet – even while using SD-WAN technology – can be unpredictable at best and subject to QoS fluctuations. On the other hand, VPNs using MPLS technology offer a way to bypass the internet and reduce potential packet loss. This network can be set up to label and prioritize voice traffic while the MPLS provider’s SLA provides a handy insurance in case of unreliability. Extra circuits can be set up to provide redundancy as well. This would be a pretty compelling reason to absorb those extra bandwidth costs, right? Not so fast.

Making Packet Loss Irrelevant

All of the above benefits will essentially disappear once you decide to host your SD-WAN in the cloud. Take VoIP for instance: while MPLS can virtually guarantee low packet loss, SD-WAN as a service tackles the jitter problem in another, better way – by making packet loss all but irrelevant. By setting a business policy to prioritize voice performance, an SD-WAN appliance can be instructed to send the same packets of voice data twice. These can then be reassembled into one signal by the SD-WAN vendor before being served to your customers. Studies have shown that over 30% of packet loss can be tolerated over SD-WAN by using this method, whereas packet loss of just 3% over MPLS can lead to noticeable quality drop. That’s one heck of a disparity. As previously mentioned, setting and changing priority rules is a much simpler and more agile process with SD-WAN, as traffic management is controlled via one central pane of glass rather than individual hardware devices, all of which have to be configured individually. SD-WAN as a managed service also comes with an SLA to cover the unlikely event of a sub-standard user experience. An added bonus, cloud-based SD-WAN can more easily incorporate the needs of remote workers who can log directly into the cloud rather than having to connect back to the on-premise network first.

The Verdict

Deciding to opt for SD-WAN as a service will, as always, depend on the specifics of your business.  If you run more than a couple business-critical, real-time cloud applications, you will definitely have to prioritize low latency. But don’t rule out SD-WAN just because you assume this level of real-time availability and performance has to involve MPLS, because it doesn’t. SD-WAN as a service, especially where the vendor’s network has a direct connection to the public cloud services you use most, can provide a comparable if not better service than MPLS at a lower cost. It really could change the landscape of enterprise IT for good. If your business is looking to escape the clutches of MPLS-dependence, there’s never been a better time to explore some alternatives. There are several cloud migration solutions available to you that can incorporate SD-WAN to provide you with a more secure cloud-based solution at a lower cost. Any transition involving your network can be daunting, but you don’t have to go it alone. Find yourself a professional SD-WAN consulting company – the best ones even offer free consulting services – who can help you navigate the complex maze of MPLS, SDN and SD-WAN and come out the other side as a company that is well-positioned for both the present and the future.