Here's a set of commands used to connect to your ISP via an ISDN dialup:
BRI0 Interface: interface BRI0/0 description Public WAN bandwidth 64 ip address negotiated encapsulation ppp dialer idle-timeout 2600 dialer string <phonenumber> dialer-group 10 isdn switch-type <switchtype> no cdp enable ppp authentication chap callin ppp chap hostname <username> ppp chap password <encrypted password> Global Parameters: ip route 0.0.0.0 0.0.0.0 BRI0/0 access-list 10 permit any dialer-list 10 protocol ip permitWhat you'll need to keep in mind is that you're going to probably need to configure/change a few of the options above. For example, the "dialer string" number will need to be replaced with your ISP's phone number. The same applies for the PPP CHAP hostname and password, where your account's username and password must be inserted.
The "ISDN switch-type" will have to be configured to the correct type. Your ISP or telephone company should be able to provide you with this information.
In closing, the above configuration is pretty standard, so it should work if all the information provided is correct. If you find yourself unable to complete the connection, I'd advise you to visit Cisco's Web site and perform a search on "ISDN Dialup" and browse through the examples given by Cisco.
This was first published in April 2005