Exploring The Basics of SD-WAN

With SD-WAN, your business data will be accessible despite internet connectivity issues and physical location. This technology lets you prioritize business-critical applications and utilize less expensive internet broadband or wireless WAN options for backup links.

In turn, this improves performance and reduces costs.


With a business-driven SD-WAN, you can ensure that data always takes the best path. It also lets you prioritize applications based on their business value, improving user performance. Finally, with SD-WAN, you can get better network security, as it provides more secure connections to the cloud and your data center.

An SD-WAN builds a virtual overlay that abstracts the underlying MPLS, internet broadband, fiber or wireless WAN links in branches and regional offices. It then centralizes network control and enables real-time application traffic management over those links.

It also simplifies network configuration and reduces the need for IT staff to program routers at branch sites manually. The SD-WAN controller can be programmed with low- or zero-touch provisioning (ZTP).

The policy-based framework is then pushed out to all network edge devices from a single place, which helps IT deliver business outcomes. This includes transport independence, which means that a branch can choose the best connection to the corporate network based on latency, throughput or reliability.

Moreover, the SD-WAN can help you save on costs. It reduces the need for expensive MPLS backhauling between the network and remote locations. Instead, traffic can be boosted over internet connectivity or public LTE links. Path optimization capabilities can also use multiple internet links, which minimizes the need to pay for unused bandwidth.


Traditional WAN architectures rely on legacy routers and a command line interface (CLI). Network engineers must manually write rules and policies for each site to define where data goes in and out of each branch office. These processes are time-consuming, costly and error-prone.SD-WAN solves these issues by combining all the networking elements into a single software platform that allows IT teams to automate much of the work.

What does SD-WAN stand for? SD-WANs offer more control and flexibility over the underlying physical infrastructure that provides private connectivity for business applications. Instead of using routers to forward traffic based on IP addresses and access controls, SD-WANs utilize real-time information to steer data over the most optimal path for each application. This helps improve data transfer speeds for customer satisfaction and employee productivity.

Finally, many SD-WANs also incorporate a variety of additional functionality to help ensure business continuity, improve the user experience and lower costs. For example, some provide the ability to load-balance between MPLS, leased internet and broadband (e.g., LTE) connections for improved performance and reliability. Others provide a secure tunnel for direct cloud access, which reduces costs by eliminating the need to backhaul data over private networks. In addition, some SD-WANs offer application optimization that optimizes data for specific applications deemed sensitive to latency and packet loss, helping to improve application performance without sacrificing security or privacy.


Organizations moving to the cloud need a secure, cost-effective way to connect their distributed users to their applications and services. Unlike traditional WAN architectures that backhaul traffic from branch offices to central Internet gateways onto the private network, SD-WANs create software-based, secure tunnels to SaaS and IaaS providers. This approach reduces WAN costs, improves performance and security and minimizes the attack surface.

Many SD-WAN solutions also provide centralized management and automation via full-featured APIs that simplify operations and scale across the entire network. This means IT can deploy and modify operational policies for the whole WAN through a single pane of glass. This saves time and money by avoiding manual configuration of edge routers, which is error-prone and complex.

SD-WAN also provides business intent-based routing, which automatically provisions and prioritizes applications based on their service level agreements (SLAs). This proactive approach ensures application performance is maintained by continually measuring WAN performance and failing over to better-performing links as needed. It also enables application optimization, which helps users work from home or when traveling for business without losing productivity due to low WAN bandwidth availability. This is achieved by combining real-time network visibility with advanced analytics that use information about the current state of a link to steer connections dynamically. This happens on the control plane, which sends connection requests from the edge to the controller and then connects the edges with the overlay network.


In the past, WANs relied on MPLS networks to connect remote locations and data centers. However, the growth of cloud adoption and mobile work prompted new bandwidth and security requirements that outpaced legacy networking solutions.

SD-WANs enable flexible WAN connectivity to meet these new demands while improving reliability and efficiency. This is done through secure, scalable connections that reduce latency and increase throughput by using multiple routes to reach the data center. They also provide more efficient bandwidth use by minimizing the data that needs to be backhauled between the branch and the data center.

These advanced capabilities make SD-WANs a great alternative to traditional MPLS VPNs and Internet connectivity services. Unlike MPLS, SD-WAN is agnostic to links and providers and can optimize for a more diverse set of traffic patterns. Additionally, SD-WAN allows IT teams to manage WAN branch routers from a central location, eliminating manual configuration.

Software running on the customer premises equipment (CPE) in an SD-WAN solution continuously monitors the performance of WAN paths. It selects the best path for each application based on existing policies and the availability of public connections like broadband Internet or 4G LTE wireless. Additionally, it can proactively steer applications to alternate routes to avoid congestion and improve network performance. Some CPEs also host security functions to enhance application and user activity visibility.