Relationship to Primary IP Interfaces
A subscriber interface operates only with a
primary IP interface
—a normal IP interface
on a supported layer 2 interface, such as Ethernet. You create a primary interface
by assigning an IP address to the Ethernet interface. Although you can configure a
subscriber interface directly on an Ethernet interface, the subscriber interface does
not operate until you assign an IP address to the Ethernet interface.
To configure a subscriber interface you must associate either a source address or a
destination address with the interface. The router receives packets on a subscriber
interface after demultiplexing the packet according to the specified source address
or destination address. You can associate multiple source addresses or multiple
destination addresses with a subscriber interface. However, a single primary interface
and its associated subscriber interfaces can only demultiplex source addresses or
destination addresses at any given time.
For example, Figure 18 on page 600 illustrates the relationship between subscriber
interfaces, an associated primary IP interface, and an associated Ethernet interface.
Figure 18: Subscriber Interfaces over Ethernet
When the router receives traffic on a primary interface, the primary interface performs
a lookup in its demultiplexing table. If the result of the lookup is a subscriber interface,
the traffic is received on the associated subscriber interface.
NOTE:
You can use the
set dhcp relay giaddr-selects-interface
command to specify
that the primary interface is identified by information in the giaddr field of DHCP
ACK messages. By default, the router identifies the primary interface based on the
interface used by the DHCP-destined packets. See “Using the Giaddr to Identify the
Primary Interface for Dynamic Subscriber Interfaces” on page 496 .
Ethernet Interfaces and VLANs
In the absence of VLANs, Ethernet does not have a demultiplexing layer. A subscriber
interface adds a demultiplexing layer for an Ethernet interface that is configured
600
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Subscriber Interfaces Overview
JUNOSe 11.0.x Broadband Access Configuration Guide
Summary of Contents for JUNOSE 11.0.X MULTICAST ROUTING
Page 6: ...vi...
Page 28: ...xxviii Table of Contents JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 36: ...xxxvi List of Tables JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 42: ...2 Managing Remote Access JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 204: ...164 Managing RADIUS and TACACS JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 292: ...252 Monitoring RADIUS Relay Server JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 336: ...296 RADIUS Client Terminate Reasons JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 368: ...328 Managing L2TP JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 444: ...404 PPP Accounting Statistics JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 494: ...454 Managing DHCP JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 510: ...470 DHCP Local Server Configuration Tasks JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 556: ...516 Configuring DHCP Relay Proxy JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 616: ...576 Managing the Subscriber Environment JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 674: ...634 Managing Subscriber Services JUNOSe 11 0 x Broadband Access Configuration Guide...
Page 767: ...Part 7 Index Index on page 729 Index 727...
Page 768: ...728 Index JUNOSe 11 0 x Broadband Access Configuration Guide...
