Demystifying Software-Defined WAN: Everything You Need to Know

Keeping up with networking technologies can take time and effort. Yet, with a new technology comes an opportunity to empower your network for success.

A software-defined WAN uses controlling software that works with various hardware platforms, making it cheaper, more flexible, and more scalable than traditional WAN architectures. Learn how to maximize the performance of your business applications with a secure SD-WAN.

WAN Optimization

No more one-size-fits-all: Forget rigid, hardware-heavy networks. What is software defined WANbrings intelligence and flexibility. It analyzes each data packet, like a detective scrutinizing clues, and sends it down the optimal path based on its type and priority. VoIP calls zip through on lightning lanes, while large file transfers take scenic detours without impacting critical traffic.

The WAN is essential to any enterprise network, but it can be challenging to manage because of latency, bandwidth limitations, and packet loss. WAN optimization helps to alleviate these problems and make the WAN run as smoothly as possible.

WAN optimization involves:

  • Using techniques like data compression.
  • Deduplication.
  • Caching to reduce WAN bandwidth usage.

This helps to improve performance and lower costs. Using these tools also helps to cut the time it takes to access files. For example, if someone has requested a file from a remote office, the information will be stored in the local cache to retrieve it much more quickly.

WAN optimization can also prioritize application traffic so mission-critical applications get the highest priority when bandwidth is limited. This feature is beneficial when deploying VoIP, video, and unified communications (UC).


One of the significant concerns about SD-WAN involves security, with many organizations looking for a solution that can protect them from cyberattacks and data loss. Many SD-WAN providers have partnered with security vendors to incorporate protection into their products and to ensure they meet enterprise security requirements.

The secure tunnels that an SD-WAN creates between branches and the cloud eliminate the need to backhaul traffic over private networks, which can be costly and introduce latency into network connections. This simplifies WAN connectivity for distributed locations and reduces the attack surface.

An SD-WAN can combine a variety of network circuits, including private multiprotocol label switching (MPLS), direct Internet access (DIA), and LTE wireless, into a single logical connection to provide bandwidth flexibility for sites. The network can also prioritize business-critical traffic to ensure it performs well over a given link. This improves application performance and helps enterprises meet their IT goals. This is especially important as more applications move to the cloud and require access from multiple locations.


A traditional WAN relies on terrestrial connections and hardware for routing information from headquarters to branches. These limitations often result in a subpar user application experience, high costs, and long deployment cycles.

A managed SD-WAN provides a more agile environment for midsize and large enterprises that connects branches to headquarters, data centers, and SaaS/IaaS services through a single centralized interface. IT can deploy, manage, and modify policies across the WAN using one platform, increasing control and flexibility.

An SD-WAN enables intelligent traffic steering based on policy, including applications and identity. Connection requests are sent from the edge to a controller, where they are assessed for the most appropriate route. The resulting connection decisions are then applied at the edge.

In addition, an SD-WAN can provide:

  • Predictive analytics.
  • Enabling IT specialists to identify potential outages or other problems before they occur.
  • Reducing resolution times and minimizing costs.

This level of network management is a significant value-add for managed SD-WAN providers and something they can offer customers at an attractive price point.


As cloud adoption grows, enterprises need a way to support SaaS and IaaS applications requiring high bandwidths and real-time performance monitoring. Traditional WANs are not designed for this type of use and create management complexity, application performance unpredictability, and security vulnerability.

SD-WAN solutions enable organizations to deploy flexible WAN connectivity that reduces costs and improves reliability and performance through a software-based approach. An SD-WAN solution uses secure internet links and encrypts traffic to create a virtualized overlay that intelligently steers network traffic via tunnels based on policy and business requirements, delivering a higher quality of service than MPLS and other legacy technology.

SD-WAN also offers security capabilities, including micro-segmentation to protect mission-critical applications and devices against vulnerabilities in other parts of the enterprise. Zero Trust security only allows network access to approved devices that have passed rigorous identity verification processes. This simplifies branch office deployment, allowing companies to quickly turn up new connections without relying on expensive WAN circuits or managed services providers. Gartner has coined the term Secure Access Service Edge (SASE) to describe a new generation of SD-WANs that combine them with necessary cloud-delivered security functions for more secure, agile, and cost-effective connectivity between data centers, branches, and the cloud/SaaS.


In addition to enabling a more agile network, SD-WAN can reduce costs by offloading traffic from costly MPLS services. It can also monitor security threats and perform deep packet inspection of applications to detect malicious activity. In addition, SD-WAN can be tightly integrated with cloud-security functions such as CASBs and FWaaS.

Rather than relying on complex rules and hardware, an SD-WAN can automate traffic steering application-driven based on business intent. This provides a high-quality user experience while improving WAN efficiency and simplifying the underlying architecture.

An SD-WAN can be managed from a single management portal to monitor and control all networking equipment. This includes routers, switches, and virtualized customer premises equipment (vCPE) devices. New sites can be deployed, software and firmware upgrades can be performed, and bandwidth can be flexed. In addition, an SD-WAN can integrate with Zero Trust security to ensure that users are verified and can only access the network resources they need. This approach to security eliminates perimeter-based attacks and protects critical data from unauthorized infiltration.

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