What Is SD-WAN?

And Why Is it Critical to Empowering Today’s Businesses?

What is SD-WAN?

SD-WAN is a software-defined wide area network architecture that enables organizations to modernize their traditional WAN networks to meet the growing needs of digital evolution. With SD-WAN solutions, organizations gain high-performance networking capabilities that support digital transformation (DX) initiatives to simplify operations and enhance business agility. 

What is SD-WAN?: Next-Level Architecture Explained

SD-WAN solutions transform an organization’s capabilities by leveraging the corporate WAN as well as multi-cloud connectivity to deliver high-speed application performance at the WAN Edge of branch sites. SD-WAN provides a centralized control mechanism that can determine and route the ideal path for traffic—MPLS, 3G/4G, or broadband—ensuring your organization can quickly and easily access business-critical cloud applications.

Traditional architectures consisted of a hub-and-spoke WAN architecture that relied on slow and expensive MPLS connectivity that offered a sub-par user experience, especially for cloud-based applications. In order for a user to access a website, traffic would first need to travel through the WAN, a security stack, then finally to the applications. In a world where most users are expecting the same high-speed broadband connectivity at work as they have at their homes, this type of legacy WAN architecture simply does not stack up.

Evolving beyond this type of traditional WAN architecture with SD-WAN enables organizations to move past archaic MPLS services and open their networks to direct internet access. SD-WAN solutions not only allow organizations to reap the rewards of Software-as-a-Service (SaaS) applications, applications in public clouds, and unified communications, but it ultimately delivers a lower total cost of ownership (TCO).

How SD-WAN Works

An SD-WAN solution connects users to any application wherever it resides from data center to the cloud. SD-WAN intelligently determines which path best meets the ideal performance needs for a specific application. It then routes the traffic through to the ideal WAN path, whereas traditional WAN architectures only have the ability to route all applications through MPLS. Below are a few characteristics that define how an SD-WAN solution works and has evolved from a WAN infrastructure:

Application Awareness

Application Awareness

With traditional WAN solutions, organizations suffer a less than ideal quality of experience and have a hard time delivering high-performance bandwidth for critical applications. Since legacy WAN architectures rely on packet routing, they lack in-depth application visibility. SD-WAN solutions, however, intelligently identify applications on the very first packet of data traffic. Network teams gain the visibility they need about which applications are used most widely across the organization, which helps them make smarter, more well-informed decisions and policies.

Multi-path Control

Multi-path Control

SD-WAN solutions enable three connections for traffic to flow through: an MPLS connection, a broadband connection, and an IPsec tunnel. The SD-WAN solution can intelligently identify applications and determine the best path it should take to maximize functionality. Moreover, multi-path technology automatically routes traffic to the next best available link in the event of an outage of the primary link. Not only does this automated capability reduce complexity within the network, but it delivers an improved user experience and improves performance of applications.

Dynamic Application Steering

Zero-Touch Deployment

SD-WAN solutions provide control and data plane separation to ensure centralized management and orchestration. SD-WAN enables faster deployments with zero-touch provisioning capabilities while doing it at scale. In addition, a unified management console for both network and security operations helps to simplify operations at WAN Edge.

Learn more about how an SD-WAN solution can modernize your organization.

Why SD-WAN: 4 Critical Benefits that Add Value to Your Business

There’s no slowing DX initiatives across organizations. As the use of business-critical, cloud-based applications and tools continue to increase, distributed organizations with multiple remote offices are switching from performance-inhibited WANs to SD-WAN architectures. SD-WAN offers business application steering, cost savings, and high-performance for Software-as-a-Service (SaaS) applications and unified communication services. Below are the top four business benefits SD-WAN solutions help organizations achieve: 

Reduce Complexity

Simplify WAN Edge services with one unified solution that delivers routing, security, WAN optimization, and SD-WAN consolidation services.

Improved Application Experience

Bolster cloud application performance by prioritizing business-critical applications and providing direct internet access at the branch.

Cost Savings

Reduce operating expenses by migrating from MPLS and utilizing multi-broadband such as Ethernet, DSL, and LTE.

Simple Management

Single-pane-of-glass management with zero-touch deployment for the entire WAN Edge simplifies deployment of SD-WAN and security.

SD-WAN and MPLS: Which is Better?

There are a handful of factors to consider before shifting an organization to an SD-WAN solution from a traditional MPLS environment. It is true that MPLS lacks the high-speed application performance and ability to seamlessly connect to the cloud that SD-WAN offers, which make SD-WAN an alluring choice. However, many SD-WAN providers still lack a true security component, which exposes organizations to new, unforeseen vulnerabilities. Since MPLS backhauls traffic to the data center, it delivers a higher level of security than providers that do not build security into their SD-WAN solution. Check out the table below to compare each option:


If security is not automatically built-in, teams need add-on options

Internet traffic backhauled to the data center

Broad application visibility

Packet routing limits visibility


Enables MPLS, broadband, LTE for high-speed

MPLS-only delivers slow performance
Scalability Easily increase capacity as needed with broadband

Lengthy process that often takes months

Cost Consolidated services greatly reduce TCO

Expensive to build and maintain


Read more about the challenges of finding a vendor that enables a Secure SD-WAN solution

Choosing an SD-WAN Vendor: Your Buying Guide

The SD-WAN market is rapidly growing with vendors eager to capitalize on the latest networking innovation. It can be difficult to navigate this complex landscape and choose the right vendor that meets the high-performance capabilities of your unique business. However, a large number of vendors still lack a highly secure SD-WAN solution, often overlooking and bypassing this critical component in a rush to go-to-market with an offering that delivers performance-only capabilities.

Modern SD-WAN solutions not only need to offer uninterrupted performance, but must also be reinforced with features to secure distributed networks from advanced cyberattacks, especially for those branch offices that also include direct internet access to online and cloud-based resources. This stark reality is why 72% of executives surveyed in a recent Gartner report about SD-WAN concerns stated that securing their SD-WAN deployment was their top concern.

Consider these key points when evaluating SD-WAN solutions: 

Product Maturity

How well established is the vendor in terms of networking and security capabilities, and how long as their SD-WAN solution been on the market? A greener vendor may lack experience and important third-party tests.


Does this SD-WAN solution come with security and networking capabilities built in? If not, this puts your organization at risk and can create networking complexity by having to add an additional security solution to the network.


Compare the cost savings for each solution. Additionally, if an SD-WAN solution lacks security, an additional cybersecurity product will ratchet up costs.

Infrastructure Integrations

How well does this SD-WAN solution integrate with the rest of your network architecture? Look for a security fabric-based solution that seamlessly integrates with other products across the network for real-time communication and threat intelligence.

For more information from third-party organizations about which SD-WAN solution is right for you, read the SD-WAN Gartner Peer Insights Review.

Read the Network Leader’s Guide to SD-WAN eBook for more on what to look for in a leading solution.

Why FortiGate Secure SD-WAN?

FortiGate Secure SD-WAN delivers built-in security plus high-speed networking capabilities, ensuring organizations gain the cloud application access and performance they need along with industry-leading protection that does not compromise speed. The Fortinet Secure SD-WAN solution has been tested and validated by NSS Labs for high-performance, security, and low TCO. Fortinet’s proven ability as a security and networking leader make it a clear choice for a complete SD-WAN solution. Below are the top reasons FortiGate Secure SD-WAN is the best option for organizations of all sizes and industries:

Next-Generation Firewall (NGFW) Security

The FortiGate NGFW delivers integrated SD-WAN networking and security capabilities in a single device.

Enhance Multi-Cloud Application Performance

Application identification, multi-path control, and application steering ensure that organizations can access all critical applications in the cloud.

Centralized Management

Fortinet Secure SD-WAN is completely managed from a central location through a single-pane-of-glass console, offering transparent visibility across the network.


FortiGate Secure SD-WAN is less expensive and delivers both networking and security in the same solution for as much as 50% better TCO versus architectures with separate security and networking devices.