isdn switch-type primary-net5
controller e1 3/0
 pri-group timeslots 1-31
interface serial3/0:15
 encapsulation ppp
 isdn protocol-emulate network
 ppp authentication chap
username grp password 0 cisco
sgbp group grp
sgbp protocol l2tp
sgbp seed-bid forward-only
sgbp member labB 192.168.1.192
sgbp member labC 192.168.1.193
sgbp ppp-forward
sgbp source-ip 192.168.1.191
sgbp dial-bids
vpdn enable