What is SD-WAN and How Does it Work?

SD-WAN technology is a modern approach to managing and optimizing a wide area network (WAN), especially for businesses with multiple branch offices or remote locations.

It enables network administrators to easily optimize their network traffic, improve network performance, and provide secure connectivity to their branch offices and remote workers.

This article will provide a simple SD-WAN overview to help you understand its meaning, working, components, benefits, and deployment procedure.

The SD-WAN technology is explained in detail in our Cisco Enterprise courses, where you will learn theory as well as practical aspects of SD-WAN technologies.

What is SD-WAN?

SD-WAN stands for Software-Defined Wide Area Network. It is a technology that uses software-defined networking principles to improve the management and operation of wide-area networks.

Traditionally, organizations used costly private lines like MPLS to connect different branch offices. But with SD-WAN, they can use regular internet connections like broadband, LTE, or even 5G, and the software will automatically manage and optimize how data travels between locations.

This helps organizations save money on expensive hardware and provides centralized control of the entire organization's network from one place.

Cisco SD-WAN Online TrainingMaster SD-WAN solutions with this online course.Explore course

Now that you understand the SD-WAN meaning, let's look at how SD-WAN functions in a network.

How Does SD-WAN Work?

SD-WAN uses software to manage how data moves across different types of internet connections, like broadband, MPLS, LTE, or 5G. It combines all these technologies to form one big network, which can be controlled by a central system.

It constantly monitors all connections and automatically chooses the best path for each type of traffic, based on speed, reliability, and the needs of the application. For example, video calls will use the fastest and most stable connection, while less critical data like emails may use a regular broadband link.

If any one link closes or is not working for any reason, SD-WAN can intelligently use another link to send the data. This smart routing improves performance and reduces costs by using a mix of available connections instead of relying only on expensive private lines.

SD-WAN also ensures data security by encrypting traffic and applying consistent security rules across all locations, even when using public internet links.

Read our article about encryption

Why is SD-WAN Important in Big IT Infrastructures?

To understand why big organizations use SD-WAN, you need to understand what these organizations used to do before SD-WAN technology.

Earlier WANs relied heavily on expensive, fixed MPLS connections, which can be rigid, slow to scale, and costly to maintain. As businesses grew and adapted cloud services, this model struggled to keep up with the need for flexibility, speed, and cost-efficiency.

But with SD-WAN, organizations can use cheaper software to manage multiple types of internet connections like broadband, LTE, and 5G, to intelligently route traffic based on application needs and real-time network conditions.

Here are some reasons why SD-WAN is important for big organizations:

● SD-WAN helps reduce network costs by up to 40% by replacing or supplementing MPLS with broadband and LTE.

● SD-WAN’s intelligent routing and real-time path selection improve app performance by 50-70% , reducing latency and jitter.

● With automatic failover and multi-path routing, SD-WAN ensures 99.99% uptime.

● Centralized management and zero-touch provisioning allow IT teams to deploy new branch sites 60% faster than traditional WAN setups

● SD-WAN includes built-in firewalls, encryption, and intrusion prevention systems, achieving up to 95% accuracy in threat detection.

Popular SD-WAN Solutions

1. Aruba EdgeConnect SD-WAN

2. Aryaka SmartConnect

3. Cato Socket SD-WAN

4. Cisco Viptela

5. Citrix SD-WAN

6. Fortinet Secure SD-WAN

7. Juniper Session Smart Router

8. VMware SD-WAN by VeloCloud

9. Prisma SD-WAN by Palo Alto Networks

10. Versa Secure SD-WAN

You can read our article about the best SD-WAN vendors in 2025

Components of SD-WAN

1. Data Plane

It handles actual data traffic between sites. Edge devices forward packets securely using tunnels, such as IPsec, and apply routing decisions based on control plane instructions.

2. Control Plane

It manages routing and policy distribution. It communicates with edge devices to enforce traffic rules and optimize path selection based on application needs.

3. Management Plane

It provides centralized visibility and configuration. Network admins use it to monitor performance, push updates, and manage policies across the SD-WAN network.

4. Orchestration Plane

Coordinates device onboarding, authentication, and connectivity. It automates deployments and ensures secure communication between all SD-WAN components.

5. Virtual Overlay Network

Creates a software-defined layer over physical connections. It abstracts transport types (MPLS, broadband, LTE) and enables secure, dynamic routing across the network.

Benefits of SD-WAN

Some of the benefits of SD-WAN are:

1. Simplified Management: SD-WAN allows network administrators to separate the control plane from the underlying hardware, enabling centralized management regardless of the network hardware in use.

2. Improved Network Performance: It enhances network performance through dynamic routing, allowing traffic to be distributed across multiple paths, including broadband, MPLS, and LTE. This increases bandwidth while reducing costs associated with traditional WANs.

3. Enhanced Security Features: SD-WAN offers robust security functionalities such as end-to-end encryption and threat detection, making it particularly beneficial for security-conscious organizations like healthcare providers, financial institutions, and government agencies.

4. Real-Time Visibility: The technology provides real-time visibility into network performance, enabling administrators to quickly identify and resolve issues, thereby streamlining network operations and improving efficiency.

5. Rapid Deployment: SD-WAN simplifies the network setup process, allowing organizations to deploy new branch offices and accommodate remote workers quickly. This is especially advantageous for businesses looking to scale operations or expand geographically.

To get professional training on SD-WAN technology, contact our learner advisors.

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What is SDN, and How is it Different from SD-WAN?

SDN (Software-Defined Networking) and SD-WAN (Software-Defined Wide Area Network) are both software-driven approaches to networking, but they serve different purposes.

SDN is used mainly within data centers or local networks. It centralizes control of network devices, allowing administrators to manage traffic and policies through software rather than hardware..

The table below shows the difference between SDN and SD-WAN:

How to Deploy SD-WAN?

Deploying an SD-WAN varies based on the SD-WAN software you are using. Cisco SD-WAN is one of the most popular SD-WAN solutions right now. We have provided a step-by-step process to quickly deploy Cisco SD-WAN.

Step 1. Define the requirements, design the topology, and identify the devices and licenses required for the deployment.

Step 2. Deploy the vManage as a virtual machine or an appliance and configure it to manage the SD-WAN network.

Step 3. Install the vBond software and configure it to provide secure device authentication and connectivity.

Step 4. Install the vSmart software and configure it to provide a centralized policy and control plane.

Step 5. Install the vEdge software on the routers and configure them to provide secure WAN connectivity.

Step 6. Use vSmart to define application-aware routing policies and security policies.

Step 7: Validate the connectivity, policies, and application performance by running tests and monitoring the network.

When Cisco SD-WAN is set up, including the controller and vedge, and cedge routers are deployed. Then vManage can be used to manage, monitor, and troubleshoot the network from a centralized location and optimize the performance.

Securing SD-WAN

As SD-WAN routes traffic over public and private networks, protecting data from unauthorized access becomes critical. Unlike traditional WANs that rely on secure MPLS lines, SD-WAN must ensure data protection across diverse internet connections.

Here are some methods of securing SD-WAN:

1. End-to-End Encryption: All data is encrypted using protocols like IPsec or TLS to protect it during transit across public networks.

2. Integrated Firewalls: SD-WAN devices often include built-in firewalls to inspect and filter traffic at the edge, reducing exposure to threats.

3. Zero Trust Access: Only authenticated and authorized users and devices can access the network, minimizing the risk of breaches.

4. Threat Detection & Response: Advanced SD-WAN solutions integrate with security platforms to detect anomalies, block malicious traffic, and respond in real time.

5. Cloud Security Integration: SD-WAN can connect with cloud-based security services (like SASE) to extend protection to remote users and branch offices.

Summing Up!

Understanding Cisco SD-WAN and its deployment steps is essential for enhancing the IT infrastructure. Cisco SD-WAN simplifies network management, improves performance through dynamic routing, and enhances security.

You can also benefit from IT infrastructure courses that cover these strategies, enabling effective implementation of Cisco SD-WAN solutions to optimize network operations and scalability in a cloud-centric environment.