User guide

Chapter 2. Planning for Router Configuration 31
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 Frame Relay
(for Frame-Relay routers)
Combined with the IP, IPX, or Bridging Network Protocols, PPP over ATM and PPP over Frame Relay share the
same configuration characteristics, except for the connection identifiers: VPI/VCI numbers are used for ATM, and
a DLCI number is used for Frame Relay.
Select the Network Protocol that applies to your situation: IP or IPX or Bridging. Collect the information
described in the appropriate section. This data will be later used to configure your router using the Command Line
Interface commands (see Configuration Tables, on page 45).
IP Routing Network Protocol
¥ System Names and Authentication Passwords
For the Target Router
This information is defined by the user. You must choose a name and authentication password for the
target router. They are used by a remote router to authenticate the target router.
For the Remote Site(s)
This information is obtained from the Network Service Provider. For each remote site, you must have the
site name and its authentication password. They are used by the target router to authenticate the remote
end. The name and password are used in both PAP and CHAP authentication. Refer to the diagram under
PAP/CHAP Security Authentication, on page 20 to see how this information is used.
Note 1: A sample configuration containing names and passwords is provided in the section Sample
Configuration 1: PPP with IP and IPX, on page 59 Chapter 3.
Note 2: If the ISP does not support the authentication of the ISP system by the caller, use the command
remote disauthen <remoteName> to disable the authentication.
¥ VPI and VCI Numbers (for ATM routers)
Your router may have been preconfigured with VPI/VCI numbers. If not, you will have to obtain these
numbers from your Network Service Provider and then configure them.
If you are connecting to multiple remote sites, you will need to obtain additional VPI and VCI numbers
from your Network Service Provider and/or Network Access Provider. These numbers identify the
remote destination and must, therefore, be unique for each remote.
¥ DLCI (for Frame Relay routers)
The DLCI number applies to Frame Relay routers only. Your Network Service Provider or your
Network Access Provider will provide you with a Data Link Connection Identifier (DLCI). The DLCI is
an address identifying your connection.