In the 2000s, MPLS had the market for enterprise WAN connectivity cornered. However, the rise of cloud computing coupled with a dramatic increase in mobile users over the last decade has created a new paradigm that MPLS simply isn’t flexible enough to service efficiently. As a result, alternatives to MPLS began to grow in popularity. For some time, there was a debate about MPLS vs SD-WAN, but now SD-WAN is emerging as a clear winner.

While there are still some use cases for MPLS and it still holds a large market share, the momentum and consensus on the way forward has become clear. For example, last year Gartner declared that SD-WAN is killing MPLS. Further, to demonstrate the growth of SD-WAN, IDC projects that the SD-WAN market will experience a 40.4% CAGR (compound annual growth rate) for the 6-year period ending in 2022.

The takeaway here is clear: SD-WAN has crossed the chasm, and mainstream adoption is here. Enterprises that stick with legacy WAN solutions such as MPLS and telco-provided VPNs (Virtual Private Networks) will miss out on the operational, performance, and cost benefits SD-WAN can bring. However, it is important to note that not all SD-WAN solutions are created equal, and cloud-native SD-WAN, a.k.a. SD-WAN as a Service or SDWaaS, is uniquely positioned to maximize the benefits of SD-WAN for enterprises.

Here we’ll explore the challenges with legacy WAN solutions and explain how SDWaaS addresses them.

The old way: multiple appliances, poor integrations, inflexibility, and security challenges

Legacy WAN solutions such as MPLS and telco-provided IP VPNs come inherent architectural challenges that hamstring WAN performance or drive up costs. For example, MPLS was designed to provide a reliable connection between two private locations (e.g. a headquarters and corporate datacenter). However, encryption is not built into MPLS (the idea is security comes from having a dedicated line) and connecting mobile users and cloud-apps with the enterprise WAN can be a challenge.

Further, the increase of Internet-bound traffic thanks to cloud computing means many enterprises still using MPLS often have to deal with the notorious trombone-routing problem. With trombone routing, traffic is inefficiently backhauled to a central location on a WAN before being sent to its destination on the public Internet. This is costly from both a performance and dollar perspective when you consider latency and the cost of MPLS bandwidth.

While telco-provided IP VPNs offer an alternative to MPLS, they come with challenges of their own as well. For example, many VPNs offer relatively lower bandwidth than alternatives which can hamper performance. Additionally, telco coverage can be limited, leading to the necessity to deal with multiple vendors to create a complete solution. This adds cost and complexity to a WAN.

Further, legacy WAN solutions often lead to a significant amount of hardware appliances and customer premises equipment (CPE) that must be deployed and maintained to enable the WAN to operate. As the WAN grows, so do the number of appliances. Not only does this mean enterprises need a team of employees with highly specialized skills to manage the equipment, it also means maintenance becomes time-consuming and difficult to manage. Updating one firewall is trivial, rolling that same update out to hundreds of firewalls requires significant coordination.

Finally, with legacy WAN solutions, integrations to support mobile users and cloud services like AWS don’t always exist. This means enterprises must either come up with their own solutions, or live with these shortcomings.  

The SDWaaS way: reduction and elimination of appliances, seamless integrations, flexibility, and integrated security

We know SDWaaS is capable of addressing the challenges of the modern WAN, but why is this the case? It is because SDWaaS is a cloud-native holistic WAN solution that brings everything an enterprise needs in WAN infrastructure under one roof.

SDWaaS offers the standard SD-WAN benefits which help solve the trombone routing problem of MPLS and add flexibility for cloud services and mobile users. As opposed to depending on expensive MPLS bandwidth, enterprises can leverage their transport method (xDSL, LTE, cable, etc.) of choice to provide connectivity. What’s more, SDWaaS does this without sacrificing the reliability MPLS users are used to. SDWaaS includes a global private backbone backed by various Tier-1 ISPs. This backbone includes an SLA uptime guarantee and Points of Presence at strategic locations around the world.

SDWaaS is built upon a variety of NCFs (network cloud functions) that are effectively cloud-native appliances (e.g. routers, firewalls, etc.) that are abstracted away from the end user. This means enterprises get all the functionality of those appliances without the need to worry about maintaining them on premises. The end result is a reduction in CPEs and elimination of many branch appliances.

These NCFs also enable the integrated security stack that further simplifies WAN infrastructure when dealing with SDWaaS. Features like NGFW (next-gen firewall), anti-malware, URL filtering, and SWG (secure web gateway) are all baked-in to SDWaaS. Since the entire solution is packaged and delivered to end users as a complete service, updates and maintenance are simplified and optimized to allow enterprises to focus less on infrastructure and more on core business functions.

As SDWaaS is cloud-based, integration for mobile users is much easier and enabling easy WAN connectivity for “road warrior” staff while on the go. Additionally, since a great deal of the SDWaaS PoPs are in or near the very datacenters as top cloud service providers such as AWS, plenty of integrations that improve the performance of cloud apps are available.

SDWaaS is the ideal fit for the modern enterprise WAN

The old approach to the enterprise WAN has become too cumbersome and inflexible to meet the needs of modern enterprises. As a result, the market has demanded alternatives. During this time, SDWaaS has emerged as the way of the future for the enterprise WAN by offering secure, scalable, and agile infrastructure while reducing complexity and cost. Over the next five years, we can expect to see SDWaaS market penetration to continue to surge and organizations that adopt the technology sooner rather than later will be best positioned to maximize the benefits.