We are using ISDN to connect to a DR site. We have a route stating to get to the remote site ethernet segment go to the remote sites BRI ISDN interface
Router A to Router B
Router A BRI interface IP address is 10.20.1.1
Router B Ethernet is 10.10.1.0/24 BRI interface ip address is 10.20.1.2
Place static route in Router A
ip route 10.10.1.0 255.255.255.0 10.20.1.2
Hope this helps
Thanks
Tom