A Software Defined Perimeter (SDP) is a security system that creates secure connections between users and resources based on who they are and the context. Instead of establishing a network boundary based on hardware, it secures individual applications and data.

A Virtual Private Network (VPN) creates a secure and encrypted connection over a less secure network, such as the internet. By encrypting data and routing it through a remote server, VPNs protect sensitive information from being intercepted by unauthorized parties or malicious actors. 

SDP vs VPN - How do they work?

SDPs are different from old-fashioned security tools because they don't rely on fixed barriers around networks. Instead, the technology hides important resources from people who shouldn't access them. SDP uses strong security checks to verify users and devices before letting them access applications and data. 

By making personalized perimeters for each user, wherever they are, SDP protects against network threats. This system improves how well you can see and manage networks, making sure only the right people get into specific resources, and reducing risks from old-style perimeter security.

On the other hand, VPNs allow users to access and transmit data privately and securely as if they were directly connected to a private network. They are commonly used to ensure privacy and security when accessing websites, applications, or resources remotely, especially in situations where public Wi-Fi networks or untrusted networks are involved. 

VPNs also enable users to bypass geographic restrictions by masking their IP address with one from the VPN server's location, allowing access to content that may be restricted based on geographical location.

What is the difference between SDP and VPN?

The main difference between a SDP and a VPN is they connect users to networks and resources. SDPs connect authorized users and authorized applications, while the VPNs establishes secure connections between devices and networks. SDP is software and identity-specific, vehicle VPNs are hardware and network-based.

However, to fully understand the differences between the two IT security technologies, we ought to compare them on their basic components, features, attributes, and common goals.

Security

In a traditional VPN setup, you give users access to your entire network once they're connected. This approach works, but it can be risky. If someone's VPN credentials get compromised, the attacker could potentially access everything on our network.

SDP flips the model. Instead of giving broad access, it uses a zero-trust model. This means everyone has to prove their identity and necessity before they get access. SDP is like a high-security building where each door requires a unique code and only opens for people who absolutely need to be there. 

For example, even if an attacker gets initial access, they can't move laterally within the network because each application or resource requires separate authentication.

When it comes to encryption, both VPNs and SDPs use it effectively. VPNs encrypt data as it travels over the public internet, ensuring our information stays private from prying eyes. 

Similarly, SDP solutions encrypt data communications, but they often take it a step further by removing network visibility to unauthorized users altogether. This means while the VPN might put your data in a secure tunnel, SDP creates a tunnel and makes it invisible on the network map to anyone without proper clearance.

Authentication is another key point of difference between SDP and VPNs. VPNs can use various authentication methods like passwords, two-factor authentication (2FA), or certificates. However, once authenticated, users often have wide-reaching access. 

SDP, on the other hand, uses continuous authentication. Every time a user tries to access a resource, their identity and permissions are re-verified. This means even if someone’s credentials are compromised, the damage is limited. 

One practical example of SDP in action is how it mitigates attacks. Suppose a phishing attempt succeeds and an attacker gains user credentials. In a VPN setup, this could be disastrous. The attacker could navigate the network freely, probing for vulnerable systems. 

With SDP, however, they would find themselves hitting walls. Every resource they try to access would require further verification, reducing their ability to cause widespread harm.

Therefore, SDP provides a more granular, controlled, and ultimately safer approach to network security compared to traditional VPNs.

Encryption methods

VPNs encrypt all traffic between your device and the VPN server, creating a secure "tunnel." This tunnel encases your data, ensuring it’s protected from end to end. For instance, when you connect to a public Wi-Fi at a coffee shop, a VPN encrypts all your internet activity, making it difficult for any prying eyes to see what you're doing.

VPNs typically use protocols like WireGuard, IPSec, and L2TP. WireGuard, for example, is highly regarded for its strong encryption capabilities, often utilizing AES-256-bit encryption. It's the same level of encryption used by banks and the military. 

But while VPNs provide robust encryption, they can sometimes slow down your connection. This happens because all your data is routed through a remote server before it reaches its destination.

On the other hand, SDP takes a different route. SDP doesn’t just create a secure tunnel; it goes a step further by implementing what's known as "zero trust" principles. This means that every connection is verified, and no one can access resources without explicit permission. 

SDP uses more dynamic encryption methods. For instance, it often employs mutual TLS (Transport Layer Security) which ensures that both the user and the server authenticate each other before a secure connection is made. 

Let’s say you’re working from home and need access to specific company resources. SDP ensures that only your authenticated device can access these resources, using strong encryption to keep the data safe. 

Unlike VPNs, SDP is more adaptable. It can dynamically adjust encryption techniques based on the type of traffic and risk levels. This leads to more efficient use of bandwidth and often results in better performance.

While both VPNs and SDP use strong encryption to protect data, the way they implement it differs significantly. VPNs are straightforward with their tunneling approach, making them great for general secure internet use. 

SDP, however, offers a more tailored and dynamic encryption method, fitting seamlessly into a zero trust security model. It's like comparing a traditional safe to a digital vault that not only locks but also constantly monitors and adapts its security based on threats.

Attack surface

VPNs have been around for a while and are pretty good at what they do. By tunneling all your traffic through an encrypted pathway, VPNs create a secure connection between your remote devices and the internal network. 

However, VPNs often expose more of your network than necessary. Because they typically operate on an “all-or-nothing” principle, once a user is connected via VPN, they usually gain access to large parts of the network. This broad access can be a significant vulnerability. 

For example, if an attacker manages to compromise a device that has VPN access, they might be able to explore various parts of your network, potentially finding weak points to exploit.

SDP takes a stealthier approach. It hides the network's resources behind a gateway until the user's identity and device are verified. This zero-trust model means that only authenticated and authorized users can see and access the specific resources they need. 

By segmenting your network and applying strict access controls, SDP dramatically reduces the attack surface. For instance, if a user only needs access to a particular application or server, SDP ensures that’s all they can see and access, keeping the rest of your network invisible and protected from potential threats.

One practical example to consider is how you handle employee access to sensitive financial data. With a VPN, once the finance team connects, they might inadvertently have access to more than just the financial servers—perhaps HR or project management systems, too. That’s more access than necessary and increases our risk. 

Conversely, with SDP, employees in finance would only get access to the financial data they need, with all other areas of the network remaining completely hidden from view.

Moreover, think about how you manage third-party contractors. With VPN, granting them access means you often have to set up complex rules and hope no one makes a mistake that exposes critical systems. 

In contrast, using SDP, you can precisely control what contractors can see and do. If a contractor only needs access to one project management tool, SDP ensures that's all they get, significantly cutting down potential exposure.

So, while VPNs do provide a certain level of security, they often leave too much of your network visible and accessible, thereby enlarging your attack surface. SDP, with its zero-trust foundation and granular access controls, keeps your network resources effectively hidden and minimizes exposure, offering you a more secure and controlled environment.

Zero trust vs perimeter security

Zero Trust and Perimeter Security are two fundamentally different approaches when it comes to securing company networks. With VPNs, the idea behind perimeter security is to create a strong, defensive barrier around your network. 

Once you get past the VPN's security layer, you've essentially gained access to the entire network. This can be a huge risk. If a cyber-criminal breaches that first layer, they can freely move around.

On the other hand, SDP operates on a Zero Trust model. Here, you assume that no user or device should be trusted by default, regardless of whether they're inside or outside the network. Every request for access is verified, authenticated, and authorized before being granted. 

Even if someone gets into the network, they can't move around without constant checks. For example, when an employee tries to access a specific application, the SDP ensures they have permission every single time they make that request.

Take the case of a remote worker using a VPN. With a VPN, once they’re connected, they might have access to resources they don’t need. This can be problematic if their credentials are compromised. Conversely, with SDP, that same worker would only have access to the applications and data they need for their job, nothing more. This vastly reduces the potential attack surface.

So, which is better? VPNs have been a staple in network security for years, the shift towards SDP and the Zero Trust model offers a more nuanced, secure, and flexible approach, especially in today's dynamic work environment.

Performance

Both SDP and VPN have their strengths and weaknesses when it comes to performance. That said, SDP generally provides a more seamless and faster experience, especially for modern, cloud-based applications. 

VPNs can sometimes feel like you’re driving through rush-hour traffic. They funnel all your traffic through a single point (the VPN server), which can create bottlenecks and slow things down, especially during peak hours. Imagine trying to stream a video and suddenly, everything buffers because the VPN server is overloaded. Not fun, right?

SDP, on the other hand, takes a different approach. SDP connects you directly to the applications you need without routing all your traffic through a centralized server. This is like having a dedicated lane on the highway that takes you straight to your destination without any stops.

For instance, if you are accessing a cloud-based app like Salesforce or Office 365, SDP connects you directly to the service. The result is faster load times and a smoother user experience.

Additionally, SDP can dynamically optimize paths based on network conditions. It’s like a smart GPS that reroutes you in real-time to avoid traffic jams. This capability can significantly reduce latency and improve performance, especially for remote teams spread across different geographies.

The difference between the two becomes particularly noticeable when using real-time applications like video conferencing tools. Zoom calls, for instance, run smoother with SDP since the connection is more direct. You’re not dealing with the same level of lag that can sometimes plague VPN connections.

To sum it up, SDP often provides a better performance experience compared to VPN, especially in environments that rely heavily on cloud applications and require real-time communication. The direct, optimized paths that SDP offers really shine in these scenarios, making it a solid choice for modern company networks.

Latency

With a VPN, all your traffic gets routed through a central server. This can create a bottleneck, especially if the server is overloaded or far away. Imagine you're in New York accessing a server in Los Angeles through a VPN server based in Chicago. Your data has to zigzag across the country, which adds time.

SDP handles things a bit differently. It’s designed to connect you directly to the resources you need without the detour. Think of it as taking a direct flight rather than connecting through multiple cities. Say you're accessing a cloud service or an internal application. With SDP, you connect straight to the resource, reducing latency significantly. It's faster because there's no middleman.

So, if you’re looking for snappy performance and less delay, SDP has the edge. It’s all about cutting out the unnecessary hops and giving you a more direct path to what you need. Which means you get your work done quicker, without the frustration of waiting.

Bandwidth utilization

VPNs often require more bandwidth. They encrypt all your internet traffic, which can be a bit heavy on the network. This can be problematic if you have a large organization with many users connected simultaneously. It’s like trying to squeeze a hundred cars into a two-lane road; there’s bound to be some slowdowns.

With SDP, the bandwidth usage is more efficient. Since it only encrypts the connections between users and specific apps, it feels less like shoving all traffic into one congested tunnel. This streamlined approach means less data overhead and, often, a snappier performance.

Even more importantly, SDP typically applies security measures at the application level rather than to all traffic indiscriminately. This means that only the data that needs to be secure is encrypted and transmitted, rather than all data. 

For instance, if you're accessing an internal document management system via an SDP, only your interactions with that system are encrypted and transported, rather than everything on your device, like it would be with a VPN.

Moreover, SDP can dynamically adjust to network conditions to optimize performance. This adaptability can result in less bandwidth consumption overall. Imagine you're on a video call and also downloading a large file. An SDP solution might prioritize the video call, ensuring it gets the necessary bandwidth for a smooth connection, while postponing the file download until there’s more available bandwidth. 

VPNs often lack this kind of dynamic bandwidth management, which can lead to congestion and reduced performance across all applications.

Therefore, while VPNs can sometimes be bandwidth hogs due to their all-encompassing encryption and lack of dynamic management, SDP offers a more refined, adaptable approach that often results in better bandwidth utilization.

Scalability

As companies grow, managing VPNs can become a bit of a headache. Imagine a company that starts with 50 employees. Setting up VPN connections for them is pretty straightforward. 

But what happens when the company doubles in size? Each new user needs to be manually configured, which is both time-consuming and prone to errors.

On the other hand, SDP shines when it comes to scalability. It makes it easy to add new users. The centralized management system it uses means you can deploy new policies and access controls with just a few clicks. This is especially useful for companies experiencing rapid growth or having remote teams scattered around the globe.

Moreover, SDP solutions can scale horizontally without the performance degradation often seen with VPNs. In large enterprises, VPN servers can become bottlenecks, slowing down the network as more users log in. 

Conversely, SDP architecture dynamically routes connections to ensure optimal performance. This makes SDP particularly attractive for industries like finance or healthcare, where secure, high-speed access is essential.

So, while VPNs have their merits, SDPs offer a more scalable solution for modern, growing companies. If you're planning for growth or already dealing with scalability issues, SDP might just be the solution you need.

Cost

VPNs might seem cheaper initially because they leverage existing infrastructure. However, the ongoing costs of maintenance, management, and potential security breaches can add up. SDP solutions might have a higher initial setup fee but often result in lower long-term costs due to reduced management overhead and improved security.

Overall, choosing between SDP and VPN depends on what's most important for your company. If you value rock-solid security, seamless user experience, and easy scalability, SDP stands out. For scenarios where the existing infrastructure is already heavily invested in VPNs, transitioning might require a more gradual approach.