Configuration Guidelines; Configuring L2Tp Avps For Relay; Configuration Tasks - Juniper JUNOSE SOFTWARE 11.2.X - BROADBAND ACCESS CONFIGURATION GUIDE 7-20-2010 Configuration Manual

JunosE 11.2.x Broadband Access Configuration Guide

Configuration Guidelines

Configuring L2TP AVPs for Relay

Configuration Tasks

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For more information about the methods for applying L2TP tunnel switch profiles, see
"Configuration Tasks" on page 386 .
The following rules apply when you configure L2TP tunnel switch profiles:
L2TP tunnel switching must be enabled for tunnel switch profiles to take effect. For
information, see "Enabling Tunnel Switching" on page 376
L2TP tunnel switch profiles have no effect when they are assigned to a LAC session
that is not tunnel switched.
The router can relay only those AVPs that are accepted at the LNS. Malformed AVPs
are never relayed.
If a tunnel grant response specifies a named tunnel switch profile that has not been
configured on the router, the router prohibits connection of the L2TP tunnel-switched
session.
If you remove a tunnel switch profile, the router also disconnects all associated L2TP
switched sessions using that profile.
In some cases, attributes configured in a tunnel switch profile take precedence over
similar attributes configured globally on the router.
For example, configuring L2TP Calling Number AVP 22 for relay overrides the l2tp
disable calling-number-avp command issued from Global Configuration mode to
prevent the router from sending AVP 22 in incoming-call-request (ICRQ) packets. In
this scenario, the router relays the Calling Number AVP.
Previously, the router did not preserve the values of incoming L2TP AVPs across the
LNS/LAC boundary in an L2TP tunnel-switched network. The router regenerated most
incoming AVPs, such as L2TP Calling Number AVP 22, based on the local policy in effect.
However, some AVPs, such as Cisco NAS Port Info AVP 100, were dropped.
In an L2TP tunnel switch profile, you can define the types of AVPs that the router can
relay unchanged across the LNS/LAC boundary. You can specify that the router relay
one or more of the following AVP types:
L2TP Bearer Type AVP 18
L2TP Calling Number AVP 22
Cisco NAS Port Info AVP 100
When you configure any of these AVP types for relay in an L2TP tunnel-switched network,
the router preserves the value of an incoming AVP of this type when packets are switched
between the inbound LNS session and the outbound LAC session.
To configure and use an L2TP tunnel switch profile in an L2TP tunnel-switched network:
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