How Should I Set Up a VoIP Network With Dual ISPs?

The best practice is to allocate one ISP for VoIP traffic and another for data traffic. This approach helps maintain voice quality by preventing congestion caused by general data usage.

To achieve high-quality and secure VoIP calls while minimizing network disruptions, configure your network to route VoIP traffic and devices through the VoIP ISP while directing data traffic and devices to the other ISP.

If using one ISP for both VoIP and data traffic:

1. Enable QoS (Quality of Service) on your router to prioritize VoIP traffic.
2. Allocate the bandwidth specifically for VoIP to prevent interference.
3. Use VLANs to separate VoIP and data traffic for better performance.

Security considerations:

1. Open UDP 10000-20000 for RTP media traffic to/from CommPeak PBX's IP.
2. Limit SIP (UDP 5060, TCP 443/5060, TLS 5061, WSS 8089) access to CommPeak PBX's IP only to prevent attacks.
3. Disable SIP ALG on routers/firewalls to avoid call issues.

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IMPORTANT

If using a shared ISP for routing both VoIP traffic and data traffic, enabling QoS (Quality of Service) is essential to prioritize VoIP traffic:

1. Enable the QoS settings to give SIP and RTP the highest priority.
2. Reserve bandwidth for VoIP to prevent congestion.
3. Monitor network usage to adjust QoS as needed.

You can check the Prioritizing Voice Traffic From CommPeak on Windows Environments article to learn how to prioritize CommPeak Softphone traffic using Windows' QoS settings.

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