hi Sir,
I'm using both the ports ( that ethernet and serial ) backside the router for communication between two location. Serial port is through satellite link and the Ethernet line through leased line.Also Im using IPSLA commands that when the leased line is down the link is alive through serial.But as the serial has very small bandwidth ,is it possible that when the leased line is down and traffic s through serial port , only one or two phones gets registerd instead of all .As I have only 64kbps bandwidth through serial or max 192Kbps. On 64 Kbps one ip (cisco 3905) phone easily gets registerd.