Systems and methods include a method for securing an Internet protocol (IP) Multimedia Subsystem (IMS)-based voice over IP (VoIP) network with multiple virtual private networks (VPNs). A call sent by a first user endpoint (UE) to a second UE is received by a SBC. The SBC provides security for an IMS-based VoIP network and controls traffic between a first VPN connecting IMS core servers, a second VPN connecting IP phones, and a third VPN connecting non-IP-phone devices. The call originates from either of the second VPN connecting the IP phones or from the third VPN connecting the non-IP-phone devices. A signaling for the call is encrypted and routed by the SBC to the second UE. A media flow for the call is encrypted and routed by the SBC through the third VPN before routing the call to the second UE.