User guide

PPPoE Functional Overview PPPoE
8-65
iMG/RG Software Reference Manual (ADSL Port)
8.7.2.2 PPPoE connections over ATM - VLAN Unaware
PPPoE connections can be established over a specific ATM channel without or without knowledge of VLANs.
If without, all PPPoE frames are untagged and are terminated directly on the IP layer without passing to the
internal CPE bridging process. This limits this PPPoE application to those solutions where the sharing of the
same ATM channel (VPI/VCI) between local PPP interfaces and internal user network traffic is not requiested.
Such a solution implies a strict routed CPE configuration where internal user network traffic can be transported
over an ATM channel already used by a PPP connection only if routed at the IP level.
The configuration of a PPPoE connection over ATM (PPPoEoA) it’s performed in a three stage process:
• First, an un-numbered IP interface (all zeros ip address) must be created:
ip add interface <ip_name>
• Second, a PPPoE transport object responsible for the PPPoE session management and PPPoE frames trans-
mission must be created and the ATM channel specified:
pppoe add transport <pppoe_name> dialout pvc <iface> a1 <vpi> <vci>
This command must specify the ATM channel coordinates (VPI/VCI) where PPPoE frames will be exchanged
(always as untagged frames only).
• Third, the un-numbered IP interface must be attached to the previously created PPPoE transport object.
ip attach transport <ip_name> <pppoe_name>
8.7.2.3 PPPoE connections - VLAN Aware
PPPoE connections can also be established with knowledge of VLANs.
In this case the PPPoE transport is associated with the VLAN - and PPPoE traffic passes through the bridge - and
flows out the ADSL interface - or an Ethernet interface - depending on the VLAN configuration.
The configuration of a PPPoE connection over ATM (PPPoEoA) is performed in a three stage process:
• First, an un-numbered IP interface (all zeros ip address) must be created:
vlan create <pppoe_vlan> 512
ip add interface <ip_name>
• Second, a PPPoE transport object responsible for the PPPoE session management and PPPoE frames trans-
mission must be created and the VLAN specified: Note that the name of the pppoe transport must be differ-
ent from the name used for the pppoe vlan.
pppoe add transport <pppoe_name> dialout eth 2 <pppoe_vlan>
• Third, the un-numbered IP interface must be attached to the previously created PPPoE transport object.
ip attach transport <ip_name> <pppoe_name>