A quick hack with Tropo.js and a Fairwaves UmSITE done by the Fairwaves and MojoLingo joint team. The idea is to limit a duration of calls on a saturated network, but to do that politely and intelligently: * we ensure users could speak for at least 30 seconds without interruption, * we drop the longest call and not a random one, * after 30 sec we politely notify them that the network is saturated and their call may be dropped, * we actually notify them right before dropping the call, * if demand is more than we can handle even by dropping long calls, we record who tried to call and notify them later, when the network resources becomes available again.