Explaining The Types of SD-WAN Architecture


Software-defined wide area network (SD-WAN) is a technology that enables businesses to connect remote locations and branch offices to the central network infrastructure using software-based techniques.

This approach offers several benefits over traditional WAN architectures, such as increased flexibility, simplified management, and improved performance. SD-WAN can be deployed in different ways depending on the specific requirements of the organization.  There are three types of SD-WAN architecture commonly used by businesses today, we’ll explain about them later in this article.

SD-WAN For Network Management Systems

Imagine a retail chain with multiple branches located across the country. Each branch has its own internet connection and hardware that is managed separately, resulting in a fragmented network infrastructure. The IT team struggles to maintain uniformity across all locations, leading to slow response times and poor user experience for both customers and employees.

SD-WAN is an MPLS alternative, it is an increasingly popular technology that provides an alternative to traditional MPLS networks. MPLS, or Multiprotocol Label Switching, has long been the preferred method for connecting branch offices and remote locations to a central network, but it can be expensive and difficult to manage. SD-WAN offers a more flexible and cost-effective solution by using software to manage the traffic flow between locations.

SD-WAN comes as a savior for such organizations by providing them with a centralized network management system that can be accessed from anywhere. By leveraging different SD-WAN architectures, businesses can optimize their traffic routing, enhance security, and minimize downtime.

The three types of SD-WAN architecture

Before we delve into the three types of SD-WAN architecture, let’s first provide an overview of how SD-WAN works. In essence, SD-WAN replaces traditional WAN routers with virtual appliances that can be centrally managed through a cloud-based controller. This enables traffic to be dynamically routed over multiple paths – such as broadband or LTE – based on real-time network conditions and application requirements.

SD-WAN can apply various security policies and protocols to ensure data confidentiality and integrity during transit. With this foundation in mind, let’s explore the three types of SD-WAN architecture further.

The first type of SD-WAN architecture is the traditional approach, which is also known as the overlay model. In this model, the SD-WAN infrastructure is installed on top of the existing network infrastructure without any modifications.

The virtual appliances are deployed at each branch location and connected to the central controller through a secure VPN tunnel. This allows for centralized management and policy enforcement for all branch locations, while still utilizing existing network hardware such as routers and switches. However, this approach may not be suitable for organizations that require more advanced features such as deep packet inspection or WAN optimization.

Comparison of SD-WAN Architectures

When considering the three types of SD-WAN architectures, it’s important to evaluate their respective benefits and drawbacks. The traditional overlay model offers simplicity and ease of deployment for organizations that have existing network hardware in place but may not be suitable for those requiring advanced features.

The cloud-based pure-play model offers maximum scalability and agility but may not provide enough control over network infrastructure for some businesses. The hybrid approach provides a balance between flexibility and control, allowing organizations to transition from traditional WAN architectures to cloud-based ones gradually. Each type of SD-WAN architecture has its own unique advantages depending on the specific requirements of the business.

To understand the differences between the three types of SD-WAN architectures, let’s use a metaphor for building a house.

The traditional overlay model is like adding an extension to an existing house. It’s quick and easy to deploy, and you can still use the same foundation and structure as before. However, if you want to add more advanced features like a new heating system or solar panels, it may require additional modifications that can be costly and time-consuming.

The cloud-based pure-play model is like building a completely new house from scratch in a remote location. You have complete control over every aspect of the design and construction process. This approach offers maximum scalability and agility for businesses that are looking to expand rapidly or have unique requirements. However, it may not provide enough control over network infrastructure for some organizations that prefer more hands-on management.

Finally, the hybrid approach is like remodeling an old house into a modern one with upgraded features such as smart home technology or energy-efficient appliances. This approach allows businesses to gradually transition from traditional WAN architectures to cloud-based ones while still retaining some control over their existing hardware.

Final Words

SD-WAN technology offers businesses a flexible and efficient way to connect their remote locations and branch offices to the central network infrastructure. The three types of SD-WAN architecture – traditional overlay model, cloud-based pure-play model, and hybrid model – each have their own benefits and drawbacks in terms of scalability, control over infrastructure components, and advanced features.

It is essential for organizations to evaluate their specific needs before choosing an SD-WAN architecture type that will best suit their requirements. With the right approach in place, businesses can enjoy improved network performance, simplified management processes, and increased security for their data transmissions.

Mark Funk
Mark Funk is an experienced information security specialist who works with enterprises to mature and improve their enterprise security programs. Previously, he worked as a security news reporter.