A virtual private network (VPN) is a marvelous tool for protecting people and their data while browsing the internet, especially when working from unsecured or weakly protected networks like those at public libraries and coffee shops.
From a business perspective, VPNs keep business data secure when employees work with sensitive material like trade secrets and proprietary information. VPN tunnels are also instrumental, as they provide users with an encrypted connection between their device and the internet.
However, given the enriched data flow and volumetric information brought on by VPNs, you and/or your IT team should still monitor them regularly. The technical feedback you can gather by doing so will help you finetune and configure your VPN connections for optimal performance.
As an alternative to VPNs, SD-WAN (Software-Defined Wide Area Network) offers businesses many more use cases. For instance, organizations that lean heavily on Voice over Internet Protocol (VoIP) phone services can use it to simplify enterprise-scale network management.
What problems does SD-WAN solve?
I’m assuming most people interested in this post are comfortable with networking basics, like WAN (Wide Area Network) that spans a large geographic area, connecting multiple local networks (LANs) across cities, countries, or even continents. So we’re going to skip the basics. If not, check out this guide on essential networking fundamentals before continuing on.
SD-WAN represents a logical progression from traditional WAN, providing benefits like dynamic traffic management with centralized control. It allows users to deploy different connection types interchangeably by using software to abstract the network layer.
The fundamental benefit of SD-WAN over traditional WAN is its ability to intelligently route traffic across multiple connection types, optimizing performance, reducing costs, and providing greater flexibility and scalability.
SD-WAN offers businesses improved network performance, cost savings, enhanced security, and greater agility by enabling dynamic, intelligent traffic routing across diverse connection types, making it a more scalable and flexible solution compared to traditional VPNs.
Let’s walk through why
Traffic optimization and improved network efficiency
A key advantage of SD-WAN is its ability to avoid vendor lock-in by using a virtualized architecture, allowing businesses to combine various transport services. Unlike traditional network infrastructure, which is often rigid and hardware-dependent, the best SD-WAN vendors give organizations the flexibility to optimize bandwidth across multiple connection types, such as broadband, mobile, Wi-Fi, and satellite.
This flexibility enables network administrators to prioritize critical traffic more effectively, reduce reliance on centralized data centers by eliminating backhauling, and create more efficient, direct routing paths to improve overall network performance.
Providing cost-effective solutions
Even though WAN connectivity has been around for a while, one of its peskiest challenges has always been figuring out how to connect widely dispersed data centers in a cost-effective manner. Technologies like MPLS (Multiprotocol Label Switching), for instance, provided a respite — especially for organizations operating in rugged environments—but MPLS often brings a huge cost disadvantage.
SEE: Discover other reasons to avoid MPLS and better alternatives.
SD-WAN, however, is more practical (to deploy) and much less expensive than MPLS because it doesn’t require specialized equipment to conduct routing over the internet.
Another cost-effective aspect of using SD-WAN is its ability to aggregate multiple, less expensive internet connections (such as broadband, LTE, and Wi-Fi) to create a more reliable and efficient network. This reduces the need for expensive, dedicated leased lines or private WAN circuits, allowing businesses to use more affordable and flexible transport services while maintaining high performance.
Increased control through application-level visibility
Nothing jams up the efforts of network administrators and cybersecurity professionals more than a lack of control over their organization’s online traffic.
That said, the application-level visibility provided by SD-WAN allows you to control traffic more effectively.
For instance, SD-WAN allows administrators to fine-tune Quality of Service (QoS) by prioritizing VoIP traffic over less critical data, ensuring consistent call quality. With real-time monitoring and dynamic traffic routing, SD-WAN can adjust network paths to avoid congestion, and ensure optimal performance for VoIP applications even during peak usage times.
Centralized management
SD-WAN is the network tool of choice for enterprises with multiple office branches that want to maintain a centralized oversight.
In general, a ton of network administrators face the challenge of having to orchestrate a gauntlet of deployed devices and endpoints, so
SD-WAN is a logical choice because it makes networks more manageable and cost-effective. With centralized management to handle data packets and workflows between branches, network operations are simplified company-wide.
Cybersecurity administration
Because of its centralized network management, SD-WAN allows you to deploy uniform security measures including dynamic encryption tunnels, IP security (IPsec), and next-generation firewalls (NGFW) to ensure that all traffic is protected. Additionally, SD-WAN offers advanced features like network segmentation, which isolates critical parts of the network to reduce risk, and intrusion protection to detect and block potential threats.
These built-in security features work together to provide end-to-end encryption, making SD-WAN a powerful solution for defending against network security threats, especially in environments with remote or distributed teams. By simplifying the process of managing network security, SD-WAN makes it easier for IT teams to protect sensitive data and maintain compliance with industry regulations.
What Problems Does a VPN Solve?
A VPN safeguards online activity by providing a measure of intrusion protection against unauthorized third parties and other rogue actors. They use encrypted data transmission to prevent the intercepting and eavesdropping of connections that can occur via packet sniffing and other snooping tactics.
The best enterprise VPN services achieve this protection through VPN tunneling, which creates an encrypted connection between the user’s device and the endpoint or remote server they are accessing. If you are potentially in the market for SD-WAN, I’d start with the enterprise VPN tools first, though you may be able to get by with the one of the best VPN solutions for small business if only a handful of your employees require the extra protections.
On the private side of things, everyday consumers use VPNs for streaming and non-commercial purposes.
Privacy and anonymity
A major role of VPNs is to provide users anonymity by hiding their identity and online activity. To achieve this, a VPN creates a private digital network from a public connection to mask the user’s IP address, making it difficult for anyone to track their internet activity.
Avoiding censorship
A VPN allows users to view content from anywhere in the world. As a result, users can access forbidden websites due to censorship or geo-restrictions. VPNs are legal in the United States, but this is not true in all countries.
Avoiding censorship and surveillance is a common practice for dissenting individuals and journalists residing in authoritarian regimes. It’s also common for people who want to stream shows that are blocked or too expensive where they live.
In addition to hiding your identity anonymously, VPNs also obscure your location by redirecting traffic through encrypted, remote servers. A good VPN ensures the user’s online activity remains invisible to their internet service provider (ISP), but it doesn’t always happen that way with all VPNs.
Providing stringent cybersecurity requirements
VPNs encrypt all data that moves through your network, fortifying and boosting an organization’s cybersecurity profile. They also minimize the effectiveness of Man-In-The-Middle (MITM) attacks, especially when employees are working remotely outside of their corporate networks. This safeguards corporate data from falling into the wrong hands if a staff member unknowingly works from a vulnerable or insecure connection.
Lastly, besides ordinary marketplace uses, many (if not all) national militaries deploy some kind of VPN for secure communication as a foundational part of their tactical kit.
Remote access connectivity
Users working off-site can use client-to-site VPNs on their personal devices to access their organization’s resources from a remote server. Naturally, remote access like this typically requires them to provide authentication credentials before they are granted access to company resources.
Setting up a remote access VPN is beneficial because you can utilize it for personal and professional purposes.
SEE: Learn more about the different types of VPNs and when to use them.
Network linking across multiple sites
Large and complex organizations often use site-to-site VPNs to scale their businesses. These VPNs enable them to combine and connect multiple internal networks across different locations within their organizations.
Intellectual property protection
VPNs enhance data security by preventing data interception in transit. This is key for safeguarding intellectual property such as trade secrets, industrial designs, and proprietary information — especially when companies need to share it with third parties and contractors.
SEE: Discover more ways to protect and secure your data.
Challenges managing access at scale with VPN vs SD-WAN
The biggest concerns with large-scale VPN deployments are performance bottlenecks from too many users, network latency issues caused by centralized traffic routing, and managing tunnels, as maintaining thousands of secure connections can overwhelm VPN servers and IT teams.
While VPNs have been a foundational tool for remote access, they face significant limitations as organizations grow. Here are the key challenges of scaling VPNs and why solutions like SD-WAN are becoming more critical for modern networks.
Scalability bottlenecks and tunnel overload:
VPNs struggle to handle large numbers of simultaneous connections, resulting in network congestion and degraded performance. Managing thousands of VPN tunnels can overwhelm servers and IT teams, creating bottlenecks that slow down critical applications and user access.
Performance and application latency:
VPNs route traffic through centralized servers, which introduces delays, especially when accessing cloud-based apps or services. This extra routing increases latency, reduces productivity, and impacts the performance of real-time applications like VoIP phone systems and video conferencing.
SEE: Learn how to future-proof your VoIP phone system.
Security gaps in modern environments:
SD-WAN’s software overlay integrates well with modern security strategies like Zero-Trust Network Access (ZTNA) , offering a secure foundation for remote and hybrid workforces. Traditional VPNs rely on perimeter-based security models that don’t account for cloud services, IoT devices, or widespread remote work. They lack built-in tools like traffic inspection, micro-segmentation, and identity-based access controls, leaving organizations vulnerable to modern threats.
Connectivity flexibility and resource management:
Unlike VPNs, SD-WAN allows you to consolidate and control traffic across multiple networks, dynamically routing traffic based on conditions like bandwidth utilization to avoid congestion and packet loss. Its flexible, virtualized infrastructure lets IT teams make rapid changes within minutes, optimizing both performance and resource allocation.
What about both VPN and SD-WAN?
As organizations grow, the limitations of VPNs — like congestion, latency, and security gaps — become more obvious. While SD-WAN offers improved scalability, performance, and flexibility to meet the needs of modern networks, many businesses are combining both VPNs and SD-WAN alongside other security technologies. This approach helps companies balance the strengths of each solution, providing secure and reliable connectivity for remote and hybrid teams.
Looking ahead, cybersecurity trends indicate that organizations will increasingly adopt integrated network solutions that blend SD-WAN, VPNs, and advanced security models like zero-trust to stay agile, secure, and ready for future growth.
