SD-WAN vs. VPN: How Do They Compare?

SD-WAN (software-defined wide area network) is a networking technology that uses software-defined networking (SDN) principles to manage and optimize wide area network (WAN) performance. SD-WAN enables organizations to securely connect users, applications, and data across multiple locations while providing improved performance, reliability, and scalability. SD-WAN also simplifies WAN management with centralized network control and visibility.

SD-WAN is a virtualized service that connects and extends enterprise networks over large geographical distances. WANs use links like multiprotocol label switching (MPLS), wireless, broadband, virtual private networks (VPNs) and the internet to give users in branch and remote offices access to corporate applications, services, and resources. This facilitates remote work regardless of location. SD-WAN appliances also monitor WAN connection performance and manage traffic to maintain high speeds and optimize connectivity.

SD-WAN solves the challenges associated with traditional WAN, providing network professionals a simpler way to optimize and secure WAN connectivity. SD-WAN is software-based and configured to handle different kinds of traffic and conditions in real time. It can adapt quickly and provides better security and reliability than traditional WANs.

What Is a VPN?

A virtual private network (VPN) establishes a VPN connection by encrypting a device’s internet connection. By creating a secure VPN tunnel, all data between the device and the internet remains confidential. Organizations employ VPNs to defend against cyberthreats, while individuals use them to maintain privacy and obscure their digital footprint. Through a VPN, a device appears to operate on the same local network as the VPN server. The VPN routes the device's traffic via its encrypted connection, enabling secure access to networks or websites remotely and concealing the device's IP address.

What Is the Difference Between SD-WAN and VPN?

When comparing SD-WAN to other networking solutions, particularly VPNs, several differences and similarities emerge.

Architecture and Functionality

SD-WAN is primarily an approach to manage wide area networks (WANs) using software-defined methods. It offers the potential for a centralized, cloud-native, and scalable system that directs traffic based on security, QoS, and business policies. VPN, on the other hand, establishes a secure tunnel between two points, ensuring that data transmitted remains confidential.

Traffic Management

SD-WAN can intelligently route traffic over a variety of connection types, from MPLS to broadband to LTE. It selects the best path based on the current network conditions, ensuring optimized performance. VPNs depend mainly on a single link, usually sending all data over this connection.

Performance Aspects

SD-WAN offers advanced features like dynamic path selection and application-aware routing, ensuring reduced latency and improved user experience. VPNs depend on the public internet and may experience latency issues, especially when data travels vast distances during high-traffic periods.

Security Implications

While VPNs inherently offer a secure data passage, potential threats exist. The public internet is their foundation, making them susceptible to a range of attacks. In contrast, SD-WAN offers end-to-end encryption across the whole network and comes integrated with modern security tools like NGFWs, SASEs (secure access service edge), and CASBs, offering an elevated security posture.

Cost Perspectives

Due to their simplicity, VPNs are generally the more economical option, particularly for businesses with fewer sites and straightforward network needs. SD-WAN, while potentially more costly, provides a comprehensive network solution with enhanced performance and security, making it more suitable for larger enterprises with complex requirements.

Maintenance and Scalability

SD-WAN stands out in terms of scalability. Its centralized, cloud-native nature means that adding new sites or adjusting policies is straightforward and doesn't require significant overhauls. VPNs, while initially simpler, can become cumbersome due to the intricacies involved in managing individual point-to-point connections.

Visibility

SD-WAN excels in network transparency, offering real-time insights into traffic and application performance. VPN, while secure, provides limited network activity views, making SD-WAN a superior choice for comprehensive visibility.

How Are SD-WAN and VPN Similar?

SD-WAN and VPN primarily function to establish secure network connections over the internet, ensuring data remains confidential and impervious to potential breaches. At their core, both technologies enable remote access to a centralized network, allowing employees and users to connect to vital corporate resources regardless of their location. This commonality stems from their inherent reliance on the internet, which allows them to operate without the need for specialized proprietary infrastructure.

Furthermore, both SD-WAN and VPN have mechanisms to route traffic. While SD-WAN has dynamic path selection based on real-time network conditions, VPNs also determine the passage of data, although in a more static manner and mostly sends traffic to a centralized VPN concentrator that impact performance and access. This routing ensures efficient data delivery and optimization of bandwidth costs. Lastly, their versatility is notable; neither SD-WAN nor VPN is limited to specific communication protocols, demonstrating their adaptability in various networking scenarios.

How to Choose Between SD-WAN and VPN

Deciding between SD-WAN and VPN hinges on a company's unique requirements. Both technologies offer secure networking solutions, but their methodologies, complexities, and advantages vary.

Understanding Organizational Needs

At the outset, it's pivotal to discern the organization's exact demands. Smaller businesses with a limited number of remote connections might find VPNs adequate due to their simplicity and affordability. In contrast, larger enterprises with expansive networks, especially those relying on cloud infrastructure, might lean toward SD-WAN for its enhanced flexibility and performance optimization.

Diving Deep into Features

SD-WAN stands out in offering real-time traffic routing based on network health, ensuring optimal data delivery. Moreover, SD-WAN amalgamates functions like LAN, WAN, security, and application performance into one platform, thereby championing a consolidated approach. Such integration becomes essential for business transformation and is beyond the reach of traditional VPNs.

n contrast, VPNs, while more basic, provide a secure channel for data transmission over the internet. They function reliably, but without the adaptive traffic management capabilities of SD-WAN, they might face occasional performance bottlenecks.

Cost Implications

While SD-WAN often carries a higher upfront cost due to its intricate design, the return on investment might be realized in the form of enhanced network performance and potential savings from reduced downtimes. VPNs, being simpler, generally incur a lower cost, making them attractive to budget-conscious businesses.

Considering Security Profiles

SD-WAN might seem inherently more exposed due to its multipoint design. However, many modern SD-WAN solutions are incorporating advanced security protocols to mitigate threats. VPNs, having been around longer, have a robust security framework, but they are not immune to cyberattacks. Plus, users can disable VPNs.

Evolution and Future Trajectory

Choosing between SD-WAN and VPN is not only a technical decision but one rooted in business strategy. Both have their merits and drawbacks. It's essential to evaluate current and foreseeable networking needs, budget constraints, and preferred scalability pathways before making an informed choice.

SD-WAN Vs. VPN FAQs