Configuration Guidelines; Configuring L2Tp Avps For Relay - Juniper JUNOSE SOFTWARE 11.0.X - BROADBAND ACCESS CONFIGURATION GUIDE 4-1-2010 Configuration Manual

If none of these methods are used, you can apply the L2TP tunnel switch profile as
an AAA default tunnel parameter. The default tunnel switch profile has lower
precedence than the other methods for applying the tunnel switch profile.
For more information about the methods for applying L2TP tunnel switch profiles,
see "Configuration Tasks" on page 390 .

Configuration Guidelines

The following rules apply when you configure L2TP tunnel switch profiles:

Configuring L2TP AVPs for Relay

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:
AAA tunnel groups
RADIUS Access-Accept messages
L2TP tunnel switching must be enabled for tunnel switch profiles to take effect.
For information, see "Enabling Tunnel Switching" on page 378
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.
L2TP Bearer Type AVP 18
L2TP Calling Number AVP 22
Cisco NAS Port Info AVP 100
Chapter 13: Configuring an L2TP LNS
Configuring L2TP Tunnel Switch Profiles
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