This document details the steps needed to be taken to configure a Cisco 1604 router for connection to MCI's InfoLink system. In all of the following steps, the router prompt will be shown in courier font and the user input will be shown in courier bold. In all examples the assumed router name will be cisco1604; it can be changed at the cisco1604(config)# prompt using the command hostname newroutername, where newroutername is replaced by the appropriate name. Also, this document assumes that the 10-base-T ethernet interface on the router has already been configured. Cisco makes it very easy to do this with the Clickstart diskette shipped with the router.
The prompt indicates the current system input mode. To use our example router name, the initial prompt upon connection to the router, either thorough the direct console connection or via telnet, and responding correctly to the Password: prompt, would be cisco1604>. In order to enter privileged mode it is necessary to use the enable command and type in the enable password at the Password: prompt.
To enter configuration mode it is necessary to type config term at the cisco1604# (privileged) prompt. The prompt will change to cisco1604(config)# at this point. Finally, once a specific interface has been specified with the interface ifname command the prompt will change to cisco1604(config-if)#. Use the exit command to move "up" a level in the heirarchy, i.e. to get from the cisco1604(config-if)# prompt to the cisco1604(config)# prompt or from the cisco1604(config)# prompt to the cisco1604# prompt.
Cisco IOS 11.3 is required for the EasyIP facility. If it isn't already loaded on the router as delivered, you will have to download it from the Cisco site and load it into the flash-card on the router. The steps are somewhat involved, especially as they require a full-featured TFTP server. Details can be provided on request.
NOTE: SPIDs are not required for all ISDN switches. If their use is required, you will be informed of these numbers upon ISDN line installation or shortly thereafter.
The numbers in this example are consistent with the remainder of the configuration commands in this document. People familiar with Cisco router configuration are, of course, free to change list numbers. In this case the username and password are those provided by InfoLink for access to the system. Note that our example includes the -ISDN suffix. Also note that we have specified the multilink option which will permit the use of both B-channels for a connection of 128Kbps.
Your output should resemble the following. Note that this is just a sample, not an operational configuration; the strings of X's would be occupied by real data.
Current configuration: ! version 11.3 service timestamps debug uptime service timestamps log uptime service password-encryption ! hostname cisco1604 ! enable secret 5 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX ! username ASTMAX1 password 7 XXXXXXXXXXXXXXXXXX username ASTMAX2 password 7 XXXXXXXXXXXXXXXXXX username ASTMAX3 password 7 XXXXXXXXXXXXXXXXXX ip subnet-zero ip nat inside source list 1 interface Dialer1 overload isdn switch-type basic-dms100 ! interface Ethernet0 ip address 10.1.1.254 255.255.255.0 ip nat inside ! interface Serial0 ip address 10.2.1.254 255.255.255.0 encapsulation ppp clockrate 56000 ! interface BRI0 no ip address encapsulation ppp dialer pool-member 1 isdn spid1 XXXXXXXXXXXXXX isdn spid2 XXXXXXXXXXXXXX ! interface Dialer1 ip address negotiated ip nat outside encapsulation ppp dialer remote-name MCI dialer string 18888515373 dialer pool 1 dialer-group 1 ppp authentication chap ppp chap hostname pselby1-ISDN ppp chap password 7 XXXXXXXXXXXXXXXXXX ppp multilink ! ip classless ip route 0.0.0.0 0.0.0.0 Dialer1 ip http server no logging buffered access-list 1 permit any dialer-list 1 protocol ip list 1 snmp-server community public RO ! line con 0 line vty 0 4 password 7 XXXXXXXXXXXXXXXXXXXX login ! end
This document does not describe the IP configuration on the "inside" of the ISDN network interface. Since all traffic flowing on the ISDN link is mapped by NAT to a single dynamically assigned external address, internal addresses lose all external significance. As long as the Cisco 1604 ethernet interface address is defined as the default route, all traffic should map correctly. For example, a PC connected to the same LAN as the router ethernet interface might have an IP address of 10.1.1.10 and should have a gateway address of 10.1.1.254 (the router.)
Copyright © 1999 by Phil Selby