Introduction
50
Model 6081RC Network Access Server Getting Started Guide
6 • PPP configuration
Introduction
In the 6081RC context, the H.110 ports act as WAN ports running bridged or routed point-to-point protocol
(PPP) connections to remote devices. For example, when the 6081RC connects to a Patton Model 3096RC via
the H.110 bus, the 6081RC will terminate bridged or routed PPP sessions originated at G.SHDSL customer
premise equipment such as Patton’s models 3201 or 3086, or PPP/G.SHDSL compliant third-party CPEs.
Traffic is directed to and from the H.110 bus by any ForeFront function card in unidirectional nx64kbps
timeslots.
The basic building blocks of the 6081RC are PPP channels. PPP channels can be bridged or routed. When a
6081RC PPP channel operates in bridge mode, data arriving on an H.110 port from remote devices is for-
warded—at the layer 2 level—to the assigned interface (Ethernet or another H.110). When a 6081RC PPP
channel is operating in routed mode, data arriving on the H.10 port(s) is routed—at the layer 3 level—to the
corresponding interface based on the destination IP address of the arriving packet.
Bridged PPP configuration
Bridged PPP connections forward data based on Ethernet frames destination addresses. Remote CPEs encapsu-
late Ethernet frames in PPP/BCP packets, and send them over the link to a 6081RC. PPP packets arriving at
the 6081RC are un-encapsulated and the Ethernet frame is forwarded to an assigned Ethernet port.
To configure a link for Bridge PPP, do the following:
1. Define an H.110 channel (see section
“Defining H.110 channels”
on page 45 for details).
2. Create a bridge group (see section
“Creating a bridge group”
).
3. Configure PPP parameters for the channel (see section
“PPP channel configuration”
on page 53).
4. Attach the Bridge/PPP to an Ethernet interface (see section
“Interface Configuration”
on page 55).
Creating a bridge group
Bridge groups are virtual modules that bridge traffic to and from the physical ports attached to the 6081RC
(H.110 and Ethernet ports, for example). In a scenario as the one below, IP traffic arriving from the remote
DSL links through a 3096RC and the H.110 ports in PPP/BCP encapsulation, is bridged (PPP/BCP encapsu-
lation is terminated) and Ethernet packets sent to the Ethernet port transparently.
ETH0-----Bridge Group 2 (BCP2)---- -----H.110 channel 1---3096RC----DSL-----3201
