Specifications

34 Chapter 2. Planning for Router Configuration

PPP Link Protocol (over ATM or Frame Relay)

The PPP Link Protocol is an encapsulation method that can be used over ATM (for ATM routers) or over Frame

Relay (for Frame-Relay routers). For PPP over Ethernet (PPPoE), see page 97.

PPP over ATM and PPP over Frame Relay use different connection identifiers:

¥ VPI/VCI numbers are used for ATM.

¥ A DLCI number is used for Frame Relay.

IP Routing Network Protocol

System Names and Authentication Passwords

For the Target Router

You define the system name and authentication password for the target router. A system name and

authentication password are required because they are used by a remote router to authenticate the target

router.

For the Remote Router(s)

The Network Service Provider defined the system names and authentication passwords for the remote

routers. You must have this information because it is used by the target router to authenticate the remote

router. The name and password are used in both PAP and CHAP authentication. To see how this

information is used, refer to the diagram under PAP/CHAP Security Authentication, on page 22 .

Note: If the NSP does not support the authentication of the NSP system by the target router, use the

command remote disauthen <remoteName> to disable the authentication process.

Note: A sample configuration containing names and passwords is provided in the section Sample

Configuration 1: PPP with IP and IPX, on page 61 .

For ATM routers, VPI and VCI Numbers

ATM uses two connection identifiers that describe the PVC (Permanent Virtual Circuit). These

identifiers are the VPI (Virtual Path Identifier) and the VCI (Virtual Channel Identifier). Your router may

have been preconfigured with VPI/VCI numbers. If not, you need to get these numbers from your

Network Service Provider.

If you are connecting to multiple remote sites, you need the unique VPI and VCI numbers that identify

the remote destinations. You should get these from your Network Service Provider and/or Network

Access Provider.

For Frame Relay routers, your DLCI

The DLCI (Data Link Connection Identifier) number applies to Frame Relay routers only. Get your

DLCI from your Network Service Provider or Network Access Provider.