I have configured two 3620 routers with a serial connection. I can ping each router from the other router. I can ping local devices on the local networks but cannot ping to a device across the WAN connection.Any suggestions?

I have little experience in cisco routers and want to use a 1601 connected to a usr 56k modem to dialup my ISP. I have tried a modem autoconfigure and the router recognises the modem however I cannot make it dial to the ISP. Can you suggest a config ...