VPN Split Tunneling Overview

VPN Split Tunneling

• VPN split tunneling is a configuration where only specific applications or traffic is routed through the VPN tunnel, while the rest of the traffic goes directly through the regular internet connection.
• This contrasts with a full VPN tunnel, where all network traffic is routed through the VPN.

Definition And Benefits

• Definition: Allows users to choose which traffic goes through the VPN and which does not, enhancing performance and flexibility compared to full VPN tunneling.
• Performance Benefits: Reduces latency and improves speed for non-VPN traffic, leading to a smoother user experience for tasks not requiring VPN security.
• Increased Network Flexibility: Users can access local resources and applications without affecting the speed of tasks that do not need the VPN's encryption or privacy features.
• Reduced Bandwidth Consumption/Saving: Only necessary traffic is routed through the VPN tunnel, conserving bandwidth and reducing strain on the VPN connection.

Configuration Methods

• Client-side Configuration: Software VPN clients provide configurable options to specify which apps or destination IP addresses to route through the VPN tunnel, letting users choose between full or split tunneling.
• Router-based Configuration: A router's configuration enables global-level traffic splits; it allows the selection of either direct internet access or VPN routing for all devices connected to the router. This often uses rules based on IP addresses or protocols.

Security Implications

• Reduced Security for Unprotected Traffic: Traffic not routed through the VPN is exposed to potential security risks on the regular internet connection, not benefiting from end-to-end encrypted VPN protection.
• Risk of Local Network Exposure: Carefully evaluating which traffic passes through the VPN is crucial to avoid a security hole. If sensitive data travels on the unencrypted traffic, it is not protected. Specific configurations, like splitting data for the internet and intranet, require careful handling of secure internal traffic.
• Potential for Malicious Software Exploitation: Traffic not routed through the VPN is vulnerable to malware, phishing, or other internet-based attacks.

Troubleshooting Techniques

• Network Connectivity Problems: To troubleshoot connection issues, verify both VPN and direct internet connectivity, isolating potential issues with either the unencrypted or encrypted traffic paths.
• Performance Issues: To address performance concerns, check the VPN connection speed, examine the traffic being routed through the VPN, and scrutinize bandwidth usage for both VPN and non-VPN traffic.
• Application-Specific Issues: Identify applications or specific websites that are not functioning correctly while using a split tunnel, to isolate problems with configuration or internet connectivity and specific traffic on the split path.

Use Cases

• Remote Access to Specific Applications: Accessing specific business applications securely without requiring all traffic to pass through the VPN connection.
• Balancing Security and Performance: Maintaining high-speed internet access for everyday tasks alongside VPN security for specific activities.
• Accessing Local Network Resources: Safely connecting to local network devices, while still allowing normal internet browsing.
• Combining VPN with Dedicated Access: Utilizing split tunneling for frequent tasks while maintaining secured access to dedicated network resources requiring VPN protection.
• Protecting Sensitive Data: Split tunneling allows users to filter sensitive data (company documents, financial logs) and route it specifically over the VPN tunnel while allowing other (non-critical) data to travel unconventionally.
• Improving User Experience: Balancing performance requirements across different internet connections.