Overview
VPNs provide valuable privacy and security benefits but can sometimes interfere with VoIP services like Quo, formerly OpenPhone. Understanding how to configure VPN settings properly ensures you maintain both privacy and reliable phone functionality.Understanding VPN and VoIP interaction
How VPNs interfere with VoIP calls and why it happens
How VPNs interfere with VoIP calls and why it happens
- Port blocking: VPNs may block ports used for voice traffic
- Traffic filtering: Some VPNs filter UDP traffic required for calls
- Latency introduction: VPN routing can add delay to real-time communication
- Bandwidth limitations: VPN overhead may reduce available bandwidth
- Specific port ranges for optimal performance
- Low-latency network connections
- Unrestricted UDP traffic flow
- Adequate bandwidth for voice quality
Maintaining privacy while ensuring call quality
Maintaining privacy while ensuring call quality
- Selective VPN usage: Disable VPN only for Quo traffic
- VPN configuration: Adjust settings to allow VoIP traffic
- Alternative privacy measures: Use other security practices
- Network optimization: Configure both VPN and Quo optimally
- Use split tunneling to exclude Quo traffic
- Choose VPN servers geographically close to you
- Select VPN protocols optimized for real-time traffic
- Consider using VPN only when not making calls
Diagnosing VPN-related issues
Quick test to determine if VPN is causing Quo issues
Quick test to determine if VPN is causing Quo issues
- Calls failing to connect when VPN is active
- Poor call quality with VPN enabled
- One-way audio issues during calls
- Connection establishment errors
- Inability to receive incoming calls
- Document the issue: Note specific problems with VPN active
- Disable VPN temporarily: Turn off VPN completely
- Test Quo functionality: Make and receive test calls
- Compare performance: Note any improvements without VPN
- Re-enable VPN: Turn VPN back on to confirm issue returns
- Works without VPN = VPN is blocking Quo
- Still has issues = Problem is not VPN-related
- Partially works = VPN configuration needs adjustment
Common VPN problems affecting calls and messages
Common VPN problems affecting calls and messages
- VPN blocking outbound connections to Quo servers
- Firewall rules preventing voice traffic
- Geographic restrictions affecting service access
- DNS routing issues with VPN servers
- Increased latency causing delayed audio
- Packet loss through VPN routing
- Bandwidth throttling affecting voice quality
- RTP traffic filtering or modification
- Push notification blocking through VPN
- Persistent connection interference
- WebSocket connection disruption
- Real-time protocol filtering
VPN configuration solutions
Required ports and IP addresses for Quo to work through VPN
Required ports and IP addresses for Quo to work through VPN
- Voice traffic ports: 10,000 - 20,000
- Protocol: UDP (User Datagram Protocol)
- Direction: Both inbound and outbound
- Priority: High (for QoS-enabled networks)
- Primary range: 54.172.60.0 - 54.172.61.255
- Secondary range: 34.203.250.0 - 34.203.251.255
- Protocol: Both TCP and UDP
- Purpose: Quo server communication
- DNS resolution must work properly
- WebSocket connections on port 443
- Standard HTTPS traffic allowed
ExpressVPN configuration for Quo compatibility
ExpressVPN configuration for Quo compatibility
- Split tunneling: Enable split tunneling feature
- App exclusions: Add Quo to excluded applications
- Protocol selection: Use IKEv2 or OpenVPN UDP for better VoIP performance
- Server selection: Choose geographically close servers
- Settings → General → Split tunneling → Manage connection on a per-app basis
- Add Quo to “Do not allow selected apps to use the VPN”
- Settings → Protocol → Select IKEv2 or OpenVPN UDP
- Avoid “Auto” protocol selection for consistent performance
NordVPN configuration for Quo compatibility
NordVPN configuration for Quo compatibility
- Split tunneling: Configure bypass for Quo
- CyberSec: Disable if causing connection issues
- Protocol: Select NordLynx or OpenVPN UDP
- Specialty servers: Avoid P2P servers for VoIP traffic
- Settings → Split tunneling → Enable → Add Quo
- Settings → CyberSec → Disable (if experiencing issues)
- Settings → VPN protocol → NordLynx (fastest) or OpenVPN UDP
- Use regular servers, not Double VPN or Onion Over VPN
Surfshark configuration for Quo compatibility
Surfshark configuration for Quo compatibility
- Bypasser: Add Quo to bypasser list
- Protocol: Use WireGuard or IKEv2
- CleanWeb: Disable if affecting connections
- MultiHop: Avoid for VoIP to reduce latency
- Settings → VPN settings → Bypasser → Route via VPN → Add Quo to bypass
- Settings → Advanced → Protocol → WireGuard or IKEv2
- Settings → CleanWeb → Disable if having connection issues
- Avoid MultiHop servers for voice calls
Corporate VPN and enterprise network configuration
Corporate VPN and enterprise network configuration
- IT department coordination: Work with network administrators
- Policy exceptions: Request Quo-specific allowances
- QoS configuration: Prioritize voice traffic in corporate policies
- Firewall rules: Add exceptions for Quo IP ranges and ports
- Alternative access methods: Configure backup connectivity options
- Mobile data fallback: Use cellular data when VPN blocks VoIP
- Dedicated VoIP networks: Consider separate networks for voice traffic
- Policy documentation: Maintain records of required configurations
Advanced optimization
Network protocol and DNS optimization for VoIP over VPN
Network protocol and DNS optimization for VoIP over VPN
- Disable UDP filtering: Ensure VPN doesn’t block UDP packets
- Buffer settings: Optimize VPN buffer sizes for real-time traffic
- Packet prioritization: Configure QoS to prioritize voice packets
- MTU optimization: Adjust Maximum Transmission Unit for efficient packet delivery
- DNS servers: Use reliable DNS servers (8.8.8.8, 1.1.1.1)
- Route optimization: Choose VPN servers with optimal routing to Quo
- Geographic proximity: Select VPN endpoints close to your location
- Carrier compatibility: Ensure VPN doesn’t interfere with carrier routing
Performance optimization and latency reduction strategies
Performance optimization and latency reduction strategies
- Server selection: Choose geographically closest VPN servers
- Protocol optimization: Use fastest VPN protocols (WireGuard, IKEv2)
- Connection method: Prefer UDP over TCP for VPN connections
- Concurrent connections: Limit other high-bandwidth activities during calls
- Speed testing: Verify adequate bandwidth with VPN active
- Traffic shaping: Configure VPN to prioritize real-time traffic
- Compression settings: Disable unnecessary compression that adds latency
- Connection monitoring: Track performance metrics during calls
- Latency: <150ms (excellent), <300ms (acceptable)
- Jitter: <30ms
- Packet loss: <1%
- Bandwidth: 100kbps minimum each direction
Alternative solutions
Privacy alternatives that don't interfere with Quo
Privacy alternatives that don't interfere with Quo
- Browser VPN extensions: Protect web browsing only
- Specific app VPNs: Route only sensitive applications through VPN
- Time-based VPN usage: Enable VPN only when not using Quo
- Network-specific policies: Use VPN on public networks, direct connection at office
- Firewall configuration: Enable device firewalls for protection
- DNS over HTTPS: Use secure DNS without full VPN
- Encrypted messaging: Use encrypted communication apps
- Regular updates: Keep all software current for security patches
- NextDNS or Cloudflare DNS for privacy
- Local firewall applications
- Browser privacy extensions
- Encrypted email services
Split tunneling configuration and best practices
Split tunneling configuration and best practices
- Whitelist approach: Only route necessary traffic through VPN
- Application exclusions: Exclude VoIP and real-time applications
- Geographic routing: Route only geographically sensitive traffic
- Performance monitoring: Track which applications benefit from VPN
- Enable split tunneling in VPN settings
- Add Quo to bypass/exclusion list
- Include other real-time apps (video conferencing)
- Keep sensitive apps routed through VPN
- Test configuration with calls
- Quo traffic will not be encrypted by VPN
- Calls still encrypted by Quo’s security
- Balance security needs with functionality
- Consider network trust level
Specific problem solutions
Poor call quality when VPN is active - choppy or delayed audio
Poor call quality when VPN is active - choppy or delayed audio
- Latency testing: Measure round-trip time with and without VPN
- Server switching: Try different VPN server locations
- Protocol testing: Test different VPN protocols for best performance
- Bandwidth verification: Ensure adequate speed for voice calls
- QoS configuration: Implement traffic prioritization
- Switch to closest VPN server (same country/state)
- Change VPN protocol to WireGuard or IKEv2
- Disable VPN encryption acceleration features
- Reduce VPN encryption level if possible
- Use split tunneling to bypass VPN for Quo
- Local VPN server: +20-50ms
- Cross-country server: +50-150ms
- International server: +150-300ms (poor quality likely)
One-way audio - can hear but not be heard (or vice versa)
One-way audio - can hear but not be heard (or vice versa)
- NAT traversal: VPN breaking NAT hole punching
- Firewall rules: Blocking return audio path
- Port forwarding: Asymmetric port handling
- STUN/TURN: Connectivity helper protocols blocked
- Enable split tunneling for Quo
- Check VPN firewall isn’t blocking UDP ports 10000-20000
- Disable VPN’s built-in firewall temporarily
- Try different VPN protocol (some handle NAT better)
- Contact VPN support about SIP/VoIP compatibility
Calls fail to connect at all when using VPN
Calls fail to connect at all when using VPN
- Signaling path: Verify SIP signaling can reach Quo servers
- Authentication: Ensure VPN doesn’t interfere with account verification
- DNS resolution: Confirm Quo servers resolve correctly
- Timeout settings: Adjust VPN timeouts for real-time requirements
- Temporarily disable VPN to confirm it’s the cause
- Add Quo to VPN bypass/split tunnel list
- Try different VPN server in same region
- Check if VPN blocks VoIP intentionally (some do)
- Use mobile data instead of VPN-protected WiFi
- Kill switch (during testing)
- DNS filtering/AdBlock features
- Threat protection
- Multi-hop connections
Intermittent issues - calls work sometimes but not others
Intermittent issues - calls work sometimes but not others
- Connection stability: VPN connection dropping/reconnecting
- Automatic reconnection: Disrupting active calls
- Server load: VPN server congestion at peak times
- Failover behavior: VPN switching servers mid-call
- Disable VPN auto-reconnect during calls
- Select specific server instead of “auto” selection
- Monitor VPN connection stability
- Use wired connection instead of WiFi
- Set VPN to use TCP instead of UDP (more stable)
- Upgrade to business VPN plan with SLA
- Use dedicated VPN server if available
- Configure static VPN connection
- Consider SD-WAN for business use
Best practices
Optimal VPN configuration for regular Quo use
Optimal VPN configuration for regular Quo use
- Enable split tunneling: Route only necessary traffic through VPN
- Server selection: Choose closest geographic server
- Protocol choice: Use WireGuard or IKEv2 for best performance
- Connection type: UDP over TCP when available
- Regular testing: Weekly quality checks
- ✓ Split tunneling enabled with Quo bypassed
- ✓ Closest VPN server selected (check latency)
- ✓ Fast protocol configured (not OpenVPN TCP)
- ✓ Kill switch disabled for Quo
- ✓ DNS properly configured
- ✓ Ports 10000-20000 UDP allowed
- Test call quality weekly
- Document working configurations
- Monitor latency to VPN servers
- Track any quality degradation
- Update VPN client regularly
When to disconnect VPN for Quo calls
When to disconnect VPN for Quo calls
- Critical business calls: Important meetings or customer calls
- High-quality requirements: Calls requiring optimal audio quality
- Low-latency needs: Real-time collaboration or emergency communications
- Troubleshooting situations: When diagnosing call quality issues
- Set up VPN client with hotkey for quick disable
- Disable VPN just before important calls
- Re-enable immediately after call ends
- Use calendar reminders for scheduled calls
- Consider automated scripts for regular call times
- Use separate device for Quo without VPN
- Configure network-based VPN bypass for Quo device
- Use mobile data for calls while computer stays on VPN
- Set up dedicated “calling hours” without VPN
Support and escalation
Information to gather for VPN-related support
Information to gather for VPN-related support
When to contact support for VPN issues
When to contact support for VPN issues
- VPN configuration doesn’t resolve issues
- Need help with port requirements
- Unclear if issue is VPN or Quo
- Business operations affected
- Need help configuring split tunneling
- VPN blocks VoIP intentionally
- Protocol or server recommendations needed
- Corporate VPN policy questions
- Start with VPN provider for configuration
- Contact Quo if VPN changes don’t help
- Provide test results to both teams
- Document all configuration attempts