What is a VPN Blocker?

Virtual private network (VPN) blocking refers to technologies that prevent the use of VPN tunnels. VPNs provide an encrypted tunnel between two points on a network, allowing users to change and hide their IP address for privacy while also protecting the data being exchanged.

Enterprises use VPNs to create secure tunnels to internal business resources across external networks. This helps secure connectivity between different branches and enables remote working strategies. But, with more platforms using VPN blockers, it is essential to understand how they work and how to get around them.

Why Do VPNs Get Blocked?

Here are the reasons why some companies use VPN blockers:

Government Censorship and Control:

By masking the user’s IP address, changing location, and encrypting traffic, VPNs are ideal for accessing content that might be banned in certain countries. Governments with censorship rules often use VPN blockers to prevent accessing specific:

• News sources
• Social media platforms
• Content from overseas

Copyright Enforcement:

VPNs can be used to distribute pirated content anonymously, making recourse difficult. In response, media companies and copyright holders often push for network tunneling prevention to protect intellectual property.

Streaming and Geo-Restrictions:

Streaming platforms like Netflix, Hulu, and Amazon Prime have regional licensing agreements, meaning their content varies from country to country. VPNs allow users to get more from their subscription by changing their virtual location and accessing additional content. Unauthorized VPN detection is common among streaming platforms to enforce geo-restrictions.

Educational Restrictions:

VPNs can be used to circumvent firewalls and secure web gateways (SWGs) to access blocked websites in educational institutions. VPN blocking may be deployed to prevent access to social media, gaming sites, or explicit content.

Gaming Platforms:

Users can spoof their location to purchase games at lower prices offered in other countries, evade bans, or make multiple accounts. This led gaming platforms to use blockers to preserve the integrity of gameplay and maintain their pricing models.

How Does a VPN Blocker Work?

VPN blockers use techniques to detect and block encrypted traffic from VPNs. Platforms may incorporate multiple VPN blocking strategies to improve the accuracy of unauthorized VPN detection and enforce their policies. The most common VPN blocking methods are:

• IP Blocking: By identifying and blacklisting known VPN server IP addresses, it’s possible to prevent traffic using network tunneling protocols. VPN providers often rent or manage large blocks of IP addresses, and platforms can track these to restrict access.

• Deep Packet Inspection (DPI): DPI analyzes the contents of data packets passing through a network. While simple firewall inspections typically only inspect the packet header, DPI examines the payload to gain a deeper understanding of the traffic’s nature. This lets platforms identify VPN traffic patterns.

• Port Blocking: Many VPN protocols use specific network ports to establish encrypted tunnels. Organizations can block these ports at the firewall level, stopping the VPN protocol from functioning.

• Transport Layer Security (TLS) Fingerprinting: A sophisticated technique that can detect VPN use, TLS fingerprinting analyzes messages during the TLS encryption protocol handshake. By analyzing how different clients send data, it’s possible to infer information and generate a TLS "fingerprint." When applied to analyzing the TLS handshake of VPN clients, it is possible to identify and block future VPN connections.

How VPN Blockers Impact Business Operations

Many businesses rely on VPNs to provide secure remote access between locations and for employees working off-site. VPN blockers disrupt these connections and have a negative impact on business operations. Here are a few real-life examples of how it can impact businesses:

• Remote Access Disruptions: Disrupting enterprise VPN controls prevents hybrid and remote workers from completing their tasks. By losing access to the corporate resources they need to complete their jobs, VPN blockers reduce productivity and leave employees idle or forced to find a workaround.

• Increased Cybersecurity Risk: VPNs provide encrypted network tunnels, which are critical for ensuring security and compliance. Frustrated employees, hindered by VPN blockers, might seek unauthorized alternatives to access sensitive data and business resources remotely. This creates security gaps and increases risk through connections that lack proper encryption or utilize shadow IT.

• Operational Complexity: Troubleshooting blocked users places extra pressure on IT teams. This drains resources, diverting the attention of staff who could otherwise be working on more strategic projects.

• Compliance Violations: Improper VPN usage and the lack of oversight it entails can lead to violations of industry regulations, particularly in healthcare, finance, or global enterprises operating under stringent data protection laws. This may lead to fines and reputational damage due to blind spots caused by VPN blocking.

How To Avoid VPN Blocks

There are various methods to get around VPN blockers and regain enterprise VPN control. Below is a series of methods and VPN blocker best practices that help bypass these tools to enable remote employees to return to work.

#1: Switch VPN Servers

One of the easiest ways to evade VPN blockers and regain access to the corporate network is to switch servers. Some network tunneling prevention platforms only rely on blacklisting IP addresses. By changing your server location, users receive a new IP address, which may not have been flagged yet.

If problems persist, you can also try using less common servers.

#2: Get a Dedicated IP Address

Another method of circumventing IP blocking is to use a dedicated IP address that is assigned specifically to you and is therefore less likely to be blacklisted. Basic VPN plans require users to share IP addresses, simplifying the task of identifying and blocking VPN traffic.

#3: Change VPN Ports

VPNs use specific ports, making it easy for networks to block their use. Switching to commonly used ports, such as TCP 443, which handles HTTPS traffic, makes it more difficult for VPN blockers to detect or interfere with your connection.

#4: Switch VPN Protocols

Not all VPN protocols are treated equally. Switching protocols changes the methods by which VPN blockers can spot your traffic, often helping avoid detection. Experiment with various protocols to determine the optimal option for your enterprise traffic. VPN protocols to consider include:

• WireGuard: Fast, lightweight, and can run on any port, making it blend in with normal internet traffic
• IKEv2/IPsec: Mobile-friendly, stable, and resistant to some blocking methods
• SSTP: Utilizes SSL/TLS encryption over port 443, which helps bypass VPN blocking techniques
• PPTP or L2TP /IPsec: Older, but still useful in low-surveillance scenarios

#5: Use Obfuscated Servers

Also called stealth VPNs, an obfuscated server disguises VPN traffic to help bypass VPN detection techniques. By routing traffic through ports used by essential services, it is harder for blockers to identify VPN use.

#6: Switch to Mobile Data

If a network is not allowing you to connect using a VPN and you’ve tried switching servers, ports, and protocols, the last thing to try is changing the network itself. While not an ideal solution for long-term enterprise use, switching from a restrictive network to mobile data can help bypass VPN blockers.

The Role of Providers in Overcoming VPN Blockers

Implementing these VPN blocker best practices largely depends on your provider and the VPN features and controls they offer. Not all VPNs offer the ability to switch connection properties or employ anti-detection technologies. By taking some time to review each provider and identify the enterprise VPN controls you need, you can ensure VPN blockers don’t impact remote workers. This includes providers with:

• A large number of VPN servers with global coverage and automatic switching capabilities
• The option of a dedicated IP address that is harder for blockers to spot
• Support for multiple VPN protocols
• Obfuscated servers designed to evade VPN detection methods

Stay Secure with Check Point Remote Access and Check Point SASE

With modern businesses requiring seamless connectivity across distributed office locations and workforces, it is crucial to identify robust remote access tools that minimize the impact of VPN blockers. Check Point’s Check Point Remote Access VPN offers just that, with support for multiple protocols and advanced VPN blocking evasion techniques.