In a site-to-site VPN setup, does 3CX proxy the SIP and audio traffic between remote locations?

In a site-to-site VPN configuration using 3CX, the system does indeed proxy both SIP and audio traffic between the remote locations. This is essential for ensuring that communication is secure and reliable across the VPN connection. The 3CX system facilitates the transmission of voice and signaling data, helping to maintain the quality of service and providing a seamless communication experience between the sites.

In this setup, SIP packets, which manage call setup and control, as well as the audio packets that carry the voice during calls, are encapsulated and transmitted through the encrypted VPN tunnel. This allows for the secure exchange of communication without exposing the information to potential eavesdropping or interference.

The proxying of both types of traffic is crucial for maintaining quality during calls, as it helps in managing NAT traversal issues and maintaining connection states, especially in environments where different network protocols and firewall configurations might interfere with effective communication. With the backing of the VPN's security features, 3CX ensures that both SIP signaling and media streams are efficiently handled, leading to improved communication outcomes.