Alcatel Carrier Internetworking Solutions Switch/Router Manuale Utente

Pagina di 1100
Page 30-5
The configuration of a T1/E1 interface is described in Chapter 33 titled “Managing T1 and E1 
Ports.” 
The configuration of a universal serial port (USP) on a WSX-S board is described in Chapter 
28 titled “Managing WAN Switching Modules.” 
Step 2. Configure the Operation of PPP Itself
The information configured at the PPP level includes the remote and local user IDs and 
passwords, network protocol information, the use of data compression, and retry and delay 
information to be used during PPP connection establishment with LCP. The UI commands 
used to configure PPP connections (called “PPP Entities”) allow for the adding, modifying, 
and viewing of PPP connections and their operational status. This chapter describes the 
configuration of PPP Entities (connection configurations) using the 
pppadd
pppmodify
pppdelete
pppview
, and 
pppstatus
 commands.
Step 3. Configure a Link Between the Physical Interface and PPP
As mentioned above, three kinds of physical interfaces can support PPP connections: 
Universal Serial Ports (on all WSX boards,), T1/E1 channels (on the WSX-FT1/E1 board), and 
ISDN lines (on the WSX-BRI board). 
The “WAN Links” used to support PPP connections vary somewhat, depending upon which 
type of physical interface is being used for PPP. When the physical interface is a Universal 
Serial Port (USP) or a fractional T1/E1 channel (which are permanent channels), the port is 
dedicated to the PPP connection and the “WAN Link” simply identifies the physical interface 
in terms of the slot and port. When the physical interface being used is an ISDN interface 
(which provides dynamic, switched connections), the “WAN Link” identifies the numbering 
information that is to be used to establish the serial connection and the slot/port if necessary. 
The UI commands used to configure WAN Links allow for the adding, modifying, and 
viewing of the links, and the display of their operational status. See Chapter 31 titled “WAN 
Links” for detailed information on the commands used to configure WAN Links.
Multiple links can be configured when employing Multilink PPP, one for each link in the 
bundle. For Multilink PPP over ISDN, each link configured for a PPP entity is called every 
time the connection is attempted and Multilink PPP is successfully negotiated. For normal PPP 
over ISDN, when a connection with a PPP entity is attempted, each link is called until one is 
successful.