Configuring Unidirectional Link Routing
UDLR Configuration Examples

IPC-516

Cisco IOS IP Configuration Guide
! helpered for the unidirectional interface.
!
interface ethernet 0
description Typical IP multicast-enabled interface
ip address 14.0.0.2 255.0.0.0
ip pim sparse-dense-mode
ip igmp helper-address udl serial 0
!
! Back channel
!
interface ethernet 1
description Back channel that has connectivity to downlink-rtr
ip address 13.0.0.2 255.0.0.0
ip pim sparse-dense-mode
!
! Unidirectional link
!
interface serial 0
description Unidirectional to uplink-rtr
ip address 10.0.0.2 255.0.0.0
ip pim sparse-dense-mode
ip igmp unidirectional-link
no keepalive
IGMP Proxy Example

The following example shows how to configure IGMP Proxy. In this example, Router C sends a PIM-SM

join message to Router B for multicast group G. Router B will send a request to Router A for an IGMP

report for group G. Router A will then forward group G multicast traffic over the UDL. Figure85

illustrates this example.