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Using VoIP with Untangle Server

As outlined in Creating User Bypass Rules, VoIP works "out of the box". Whether your Untangle Server is a bridge or gateway, Untangle Virtual Machine (UVM) scans all packets in order to protect your network. VoIP packets are very time-sensitive, so without bypass rules, there is no way for Untangle Server, or any similar router for that matter, to scan the packets fast enough, resulting in disconnects or undesirable voice quality. These VoIP packets aren't meant to be scanned, so Untangle Server is preconfigured with a bypass rule to prevent performance and reliability problems. However, VoIP technology has its challenges that are independent of your Untangle Server.

There are essentially a few VoIP implementations:

• Typical LAN phone → ATA → Ethernet → Router (Untangle Server) → Internet → VOIP Service Provider
• IP phone hardware → Ethernet → Router (Untangle Server) → Internet → VOIP Service Provider
• IP phone hardware → Ethernet → Router (Untangle Server) → Internet → Router → Ethernet → IP phone hardware
• IP phone software → Ethernet → Router (Untangle Server) → Internet → Router → Ethernet → IP phone software

Separate voice and data networks are ideal in any configuration, but Untangle recognizes that users don't have the luxury of dedicated networks. It's not uncommon to have an Untangle Sever between IP phone hardware or software. Untangle bypass rules and Untangle QoS provide solid support for VoIP over a shared internet connection.

In some cases your service provider might prevent you from using VoIP. As a result, some non-Untangle users resort to creating VPN tunnels between the caller's router and the sender's router. When you choose a service provider, choose one that supports VoIP. Also, VoIP over VPN works with Untangle Server using IPSEC, but Untangle doesn't recommend VoIP over OpenVPN at this time. Untangle Server has a great VPN product, but VoIP over VPN produces poor results (for example, dropped calls). However, if you want to use VoIP over OpenVPN, Untangle wants to help improve your experience, so let us know if you have any difficulties, and we'll help you out.

To learn about VoIP, go to voip-info.org.