Packet Detection; Figure 21: Ip Over Ethernet Dynamic Subscriber Interface Configuration - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - BROADBAND ACCESS CONFIGURATION GUIDE 2010-10-12 Configuration Manual

JunosE 11.3.x Broadband Access Configuration Guide

Figure 21: IP over Ethernet Dynamic Subscriber Interface Configuration

Packet Detection

604
IP over Ethernet
IP over VLAN over Ethernet
IP over bridged Ethernet over ATM
For example, Figure 21 on page 604 shows the interface stacking in an IP over Ethernet
dynamic subscriber interface configuration. The illustration indicates which layers in the
stack are static and dynamic, and identifies the CLI commands typically used to create
the configuration.
As shown in Figure 21 on page 604, issuing the ip auto-configure ip-subscriber command
configures the primary IP interface to enable dynamic creation of subscriber interfaces.
However, the router does not actually create the dynamic subscriber interface until the
DHCP server assigns an IP address to the associated subscriber.
To configure each supported configuration, see "Configuring Dynamic Subscriber
Interfaces" on page 613.
For GRE tunnel interfaces, the event that triggers dynamic creation of subscriber interfaces
occurs when the router receives a packet with a source IP address that is not in the
demultiplexer table. In this case, the primary IP interface must be in autoconfiguration
mode.
Packet detection is the only method of dynamically creating subscriber interfaces on
GRE tunnel interfaces; you cannot use DHCP local server or DHCP external server.
Issuing the ip auto-configure ip-subscriber command configures the primary IP address
to enable dynamic configuration of subscriber interfaces. Unlike DHCP configurations,
the router creates the dynamic subscriber interface when it receives the first packet that
contains the subscriber's IP address as the source address.
In addition, a dynamic subscriber interface becomes inactive after a period of time in
which the router receives no packets that contain the subscriber's IP address as the
source address. You can configure the period of time by issuing the ip inactivity-timer
command.
To configure dynamic creation of subscriber interfaces on GRE tunnel interfaces, see
"Configuring Dynamic Subscriber Interfaces" on page 613.
Copyright © 2010, Juniper Networks, Inc.