This is gonna an important topic What VOIP can do with WiFi mesh? I can say this is the topic which might be useful for saving your expense in local calls. If your city is already WiFi enabled just think of the situation where you don’t need to pay phone bills for local calls? I know you will be interested. If your city is WiFi enabled this dream can be setup without enough cost. But this is heavily dependent on your network. There are couple of requirements that need to be satisfied.
1) WiFi mesh
2) SIP server
3) SIP clients
Another main requirement is your bandwidth and its reliability. Make your WiFi mesh reliable for voice handling. Any packet loss in voice handling may disrupt its quality of service(QoS). Another major factor is its latency. IPERF is a measurement tool to find the QoS. This tool measures mainly node to node throughput, latencies, jitter, packet loss etc. If the QoS achieves certain level, we can deploy Voice solution with the existing WiFi mesh network. SIP server may be open source asterisk solutions or some Hardware capable to accept SIP protocols.
Now a days high end phones are equipped with WiFi chip. So we can install a SIP based application and use it in the existing mesh network for local voice call. I am planning to setup a asterisk based solution in one of our mesh network for testing purpose so that I can analyze the reliability.