Jason, This is my IOS config for a 1721 but should work on other routers with an AUX port. The aux port corresponds to line 5 (show line will identify it). Encapsulation is set to slip but you can also set it to ppp. Connection to a PC serial port is via a normal Cisco (blue) rollover cable. ! interface Async5 ip address 192.168.44.1 255.255.255.0 encapsulation slip async mode dedicated ! ! line aux 0 modem InOut transport input all flowcontrol hardware rxspeed 19200 txspeed 19200 ! ! I would be most interested to see your perl script Regards, Nick.