Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010, Руководство по настройке

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On receipt of a packet, the router creates all dynamic layers above the ATM 1483
layer, starting with the lowest dynamic layer. For example, in the case of a dynamic
PPPoE interface, the router creates the PPPoE interface first, then the PPP interface,
and then the IP interface.
If any layer of the dynamic portion of the interface column fails to be created, then
the interface creation fails and the connection is denied. All dynamic layers above
the ATM 1483 subinterface are destroyed, starting with the highest dynamic layer.
When you configure a dynamic interface, you must assign (or create and assign) a
profile to the interface. Profile creation and assignment topics are discussed in depth
in “Configuring a Dynamic Interface from a Profile” on page 563.
About Configuring RADIUS for Dynamic Interfaces
Dynamic interfaces can be configured automatically through authentication and
authorization by the RADIUS server.
On ATM interfaces, you initially create the static portion of the interface column by
creating an ATM interface, ATM 1483 subinterface, and underlying ATM permanent
virtual circuit (PVC).
subscriber Command
For dynamic interfaces that do not have a PPP layer, such as IPoA, you can use the
subscriber command to configure an ATM 1483 subinterface to be authenticated
automatically by the RADIUS server. The subscriber command uses a RADIUS
username and optional password for identification and is available only for bridged
Ethernet and IPoA configurations. This command is used for dynamic encapsulations
that do not provide the authentication information remotely, as PPP does.
For dynamic interfaces with a PPP layer, the RADIUS username and password are
obtained from the remote client, and authentication is performed with the RADIUS
server. The attributes obtained from RADIUS can then be used to configure any
higher-layer dynamic interfaces, such as IP, that are built over PPP.
For more information about using the subscriber command, see “subscriber” on
page 556.
Authenticating Subscribers on Dynamic Bridged Ethernet over Static ATM
Interfaces
You can use either of the following methods to configure and manage RADIUS
authentication for IP subscribers on dynamic bridged Ethernet over static ATM
interfaces:
■
The subscriber command
■
The subscriber management application
The subscriber command does not support running stateful SRP switchover (high
availability) on the router. Therefore, the configuration method you choose depends
on whether stateful SRP switchover is or is not running on your router.
About Configuring Dynamic Interfaces over Static ATM
■ 523
Chapter 17: Configuring Dynamic Interfaces