How Does a VPN Work?

Virtual Private Networks (VPNs) provide secure and private connections when using public networks. They encrypt internet traffic and route it through a remote server, changing the original IP address and preventing third parties from intercepting data.

They offer a range of benefits to both consumers and businesses, including:

• Masking IP addresses
• Encrypting sensitive data
• Accessing blocked online content

For businesses, VPNs enable secure access to internal resources from any location. Before going into detail on the benefits and business use cases of VPN services, let’s start with the basics.

How a Standard Internet Connection Works

A standard internet connection sends data from your device to the internet via your Internet Service Provider (ISP). This data packet contains:

• A header
• A payload (the actual data being transferred)

The header includes information such as:

• The IP address of the original device
• The destination

If you’re using HTTPS (Hypertext Transfer Protocol Secure), the payload is encrypted—but the header remains visible. This means your IP address is still accessible to:

• Your ISP
• The websites or services you interact with

This allows them to block content based on your IP address location or build a profile of your activity for targeted marketing.

What Changes When You Use a VPN

While there are various types of VPNs, they all insert an intermediary step into this process to improve security and privacy. When using a VPN:

• All data leaving your device is encrypted
• The encrypted data still travels through your ISP, but they can no longer see the content or destination

The Role of the VPN Server

The data is routed to a remote VPN server, where it is decrypted and forwarded to the intended website or service. The source IP address becomes the VPN server’s IP, not yours. This masks your IP address and location, adding a layer of anonymity and security.

The response from the website follows the same route:

1. Sent back to the VPN server
2. Encrypted again
3. Then returned to your device

VPN Protocols and Tunneling

When you connect to a VPN server:

• The connection is authenticated
• Data is encrypted and transferred through a secure tunnel

All of this is managed by the VPN protocol in use.

VPN Protocols Explained

A VPN protocol acts as a system of instructions defining how the connection is made, including:

• Authentication: Ensuring only legitimate traffic is routed through the VPN server. Authentication defines the mechanism by which the VPN verifies a user’s identity.
• Encryption: The encryption standard used by the VPN provider. Stronger VPN encryption standards are harder to break.
• Tunneling: Encapsulates data to securely transfer it between two points on a public network. This masks the data packet’s header information, preventing network components from identifying the IP addresses of its source and destination.
• Data Integrity: Verifying that the data transmitted via the VPN service has not been tampered with or altered as it moved between the user and the website or service.

There are a number of popular VPN encryption protocols used by different providers. The performance of each varies in terms of security, speed, stability, and compatibility, making them better suited to various applications. The most commonly used VPN protocols are:

• OpenVPN: A popular open-source protocol that utilizes SSL/TLS VPN encryption while being highly configurable and widely supported. OpenVPN can be slower compared to newer VPN protocols.
• L2TP (Layer 2 Tunneling Protocol): Usually paired with Internet Protocol Security (IPSec) for VPN encryption, L2TP is an older protocol that is supported by many operating systems. However, its performance is slower than that of newer protocols, and it has issues with firewalls and Network Address Translator (NAT) gateways blocking data.
• IKEv2 (Internet Key Exchange version 2): Another protocol that is typically utilized with IPSec for encryption, IKEv2 offers stable VPN connections that are resilient to network changes. This means they are often used for mobile VPN clients. IKEv2 does have limited platform support compared to OpenVPN, though.
• PPTP (Point-to-Point Tunneling Protocol): One of the oldest VPN protocols, PPTP is very fast and easy to set up. While some legacy systems still use it, PPTP is rare today due to its weak encryption.
• WireGuard: A more modern, lightweight protocol known for its speed and security. WireGuard is becoming a popular protocol across many different VPNs.
• SSTP (Secure Socket Tunneling Protocol): A protocol developed by Microsoft, SSTP is good at bypassing firewalls. However, it has limited support on non-Windows platforms.

VPN Use Cases

Typical use cases of VPNs include:

• Providing Secure Remote Access: VPNs allow employees to access internal resources from outside the office. Remote or hybrid workers can use a VPN to make a secure connection to the company’s private network over the public internet, encrypting all data.
• Connecting Multiple Office Locations: VPNs provide a secure and cost-effective method of connecting different branch locations over the internet. Businesses can enable seamless data sharing and centralized resource access by creating a site-to-site VPN tunnel between offices.
• Complying with Regulations: VPN encryption helps organizations in regulated industries to comply with data privacy requirements. Data shared with users or third parties outside the network is automatically encrypted using a VPN.
• Supporting Global Operations: By changing IP addresses, VPN users can access geo-restricted content wherever they are located. This helps support businesses with global operations for testing regional websites, consistent platform access, or performing international market research.

The Benefits of Using a VPN

A VPN is designed to create an encrypted tunnel between two points. Both endpoints have a shared secret key, which allows them to encrypt their outgoing traffic and decrypt incoming traffic. This shared secret key might be derived from a user’s password or derived via a key sharing protocol. The exact mechanics depend on the VPN protocol in use.

What Are the Benefits of a VPN Connection?

The purpose of a VPN is to provide employees with secure remote access to corporate resources. Some of the benefits of a VPN connection include:

• Data Security: VPNs encrypt traffic between a remote worker and the corporate network. This helps to protect their traffic against eavesdropping and MitM attacks.
• Greater Visibility: Remote users can directly access the Internet and an organization’s cloud-based resources. With a VPN, all traffic flows through the corporate network, allowing the organization to inspect and secure this traffic.
• Perimeter Security: A VPN routes remote users’ traffic to inside the corporate network perimeter. This enables the organization to protect them and manage their traffic with existing, perimeter-based solutions.
• Local Addressing: With a VPN, remote users are treated like they have a direct connection to the corporate network. This enables an organization to use local addressing for all users, both on-prem and remote.

Types of VPNs

Numerous VPN protocols exist, some of which are more secure than others. Some of the main types of VPNs include:

• Remote Access VPNs: Remote access VPNs use custom VPN protocols to provide a remote worker with access to the corporate network. Some commonly used VPN protocols include IPsec and OpenVPN.
• SSL VPNs: SSL VPNs use an encrypted HTTPS connection to act as a VPN. This approach has the advantage that encrypted web traffic (HTTPS) is permitted through most firewalls and doesn’t require specialized software.
• Cloud VPN: Cloud VPN allows businesses to move their VPN hosting to the cloud for better access to their existing cloud-based resources.
• Site-to-Site VPNs: Unlike the other two types of VPNs, site-to-site VPNs don’t connect a remote worker to the corporate network. Instead, it securely links two of an organization’s sites over the public Internet.

Is a VPN Secure?

Cybersecurity protocols and systems are often evaluated based on the “CIA Triad”. This refers to the system’s ability to provide:

• Confidentiality: Protecting sensitive data against unauthorized access. A VPN’s primary goal is to provide confidentiality through its use of encryption.
• Integrity: Protecting data against unauthorized modification. A VPN can provide integrity protection if it uses an authentication cryptographic algorithm.
• Availability: Ensure that the system remains available to users. VPNs have some availability concerns since they require a certain amount of bandwidth and for the remote endpoint to have the capacity needed to support a user’s traffic.

Limitations and Security Risks of VPN

VPNs are not a perfect remote access solution, leading some organizations to pursue VPN alternatives. Some of the main limitations of VPNs include:

• Lack of Integrated Security: VPNs provide secure remote access to the corporate network. However, they lack any built-in network security capabilities to identify malicious content, data exfiltration, or other security risks within those connections.
• Inefficient Routing: VPNs are a point-to-point networking solution that can provide a remote worker with access to a particular point on a corporate network. With the growth of cloud-based infrastructure, this can result in increased latency as traffic is diverted through the corporate network en route to its intended destination.
• Network Complexity: As a point-to-point solution, VPNs only provide a secure connection between two locations. This can result in complex network infrastructure for organizations with multi-cloud and multi-site network infrastructure.
• Limited Scalability: Traditional physical VPN appliances have a maximum amount of traffic that they can handle. With the growth of remote work, these scalability limitations can result in degraded efficiency or employees adopting insecure workarounds.
• Software Vulnerabilities: VPN endpoints became a major target of attack with the rise of remote work. Vulnerabilities in these devices can be exploited to gain unauthorized access to corporate networks.

VPN vs. Alternative Remote Access Solutions

There are alternative remote access solutions you can implement to achieve higher security.

Zero Trust Network Access (ZTNA)

ZTNA is a security framework that removes implicit trust to continually verify and authenticate user identity. Business attack surfaces are expanding as more organizations utilize a mix of hybrid cloud and on-premises infrastructure. This means broad network access, as provided by VPNs, introduces new security risks that require additional controls beyond encryption.

ZTNA and least-privilege access (providing only the access needed for a given role) help limit attack surfaces by:

• Allowing users access only to specific systems
• Preventing lateral movement within networks
• Reducing the severity of a data breach, since attackers struggle to compromise more systems

ZTNA also promotes strong authentication and authorization processes by:

• Routing access requests through an access broker
• Granting access only to the specific application needed
• Avoiding the full network access typically granted via VPNs

Given how VPNs work, users are often provided with blanket access. In contrast, ZTNA offers more controlled, application-level access that prioritizes security and limits the impact of attacks.

Secure Access Service Edge (SASE)

SASE combines the connectivity of a Wide Area Network (WAN) with a range of security technologies and frameworks, including:

• Zero Trust Network Access (ZTNA)
• Cloud Access Security Broker (CASB)
• Secure Web Gateway (SWG)
• Firewall-as-a-Service (FWaaS)

Delivered as a single, cloud-based solution, SASE unifies networking and security capabilities for simpler operations. While VPNs are best suited to on-premises IT architectures and providing external users with internal access, SASE:

• Distributes functionality across the cloud
• Delivers services at the network edge

SASE is designed for the needs of modern workloads, where traffic is increasingly directed to:

• SaaS applications
• Other cloud services, rather than on-prem data centers

Its security architecture ensures:

• Consistent security policies
• Access control, regardless of user location or the service/application in use

Software-Defined Wide Area Network (SD-WAN)

An SD-WAN offers a software alternative to managing the infrastructure needed to connect multiple branch locations or provide remote access. Rather than controlling network access by adjusting network devices, it achieves this through centralized software. This enables dynamic routing based on:

• Application needs
• Bandwidth availability
• Security policies

While SD-WANs are a networking framework and not a security tool like a VPN, they often provide security capabilities as well as connectivity. This includes encryption without some of the performance limitations of a VPN tunnel.

What Should You Consider When Choosing a VPN?

While there are alternatives that enable remote network access, VPNs remain a widely supported and easy-to-implement option. When choosing a VPN for your business, there are a number of factors you need to consider.

The most prominent factors include:

• Network Scale: The number of employees and locations that make up your business. You need to understand the scale of your operations and find the right VPN provider for your needs. For example, how many staff work remotely, at least some of the time? Where are your centralized resources stored? How many locations do you need to connect using site-to-site VPNs?
• Security: The main security factor to consider is VPN encryption. Look for solutions that rely on strong, modern encryption standards. Beyond encryption, there is a range of other VPN security features vendors provide. These include authentication, kill switches, leak protection, and malware blocking.
• Speed: Defined by the VPN protocol and the number and location of VPN servers operated by the vendor. Network speeds impact user experience, so consider VPNs that have a minimal impact on latency.
• Integration: How the VPN integrates with the existing IT infrastructure and user devices. This depends on the VPN protocol’s compatibility with operating systems, browser extensions, cloud environments, and other security tools.
• Management: Whether or not the VPN is easy to use and provides comprehensive visibility into network connections.

Stay Secure with Check Point Remote Access VPN

Check Point’s Check Point Remote Access VPN offers high-level security and fast network speeds regardless of the scale of your operations and your existing infrastructure. With a simple user experience, employees can quickly set up Check Point on any device and start accessing internal resources securely.

Plus, IT teams can configure and manage all VPN connections from a single, integrated console.

Security features include:

• Multi-factor authentication.
• Endpoint system compliance scanning.
• Encryption of all transmitted data using IPSec or SSL.