A switched telephone network is arranged in a manner to enable packet voice communication between telephone terminals via multiple redundant packet switched networks. The packet switched networks may utilize different protocols, be operated by different entities, and have primary functions other than voice communication. One example of such a network may be internetworked networks, such as the Internet. One example of an alternate packet switched network may be a network whose primary function is control of a circuit switched telephone network. The common channel interoffice switching system (CCIS) of a public switched telephone network (PSTN) is a preferred example.A voice communication link may be established from telephone terminal to telephone terminal via the Internet, the quality of voice communication may be monitored, and the link may be transferred to the common channel interoffice signaling network if and when the quality of voice communication deteriorates beneath a pre-established norm. There is provided a means for monitoring the links of the common channel interoffice signaling system carrying the packetized voice communication and collecting the information needed to permit charging for the voice communication by time duration or by cells used to carry the packetized voice signal. The customer may be provided with the option of establishing the norm for diversion of the communication, or may elect which path is to be selected as the primary path.