Juniper JUNOSE 11.2.X IP SERVICES, Configuration Manual

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The access node sending a single copy of the multicast stream to a specific access node
is a more efficient use of the bandwidth. Using this method, the access node performs
the multicast replication for subscribers that reside beyond the access node.
ANCP transactional multicast enables the E Series router to set up a multicast replication
state in the access node. In Asynchronous Transfer Mode (ATM) access networks, the
B-RAS can use the ANCP to set up point-to-multipoint cross-connects in the access
nodes.
OAM
A simple solution based on ANCP provides B-RAS with an access-line test capability.
When enabled through the CLI, the B-RAS uses an ANCP message to trigger the
access-node to perform a loopback test on the local loop (between the access node
and the CPE). The access node reports the results of the test by means of another ANCP
message.
Retrieval of DSL Line Rate Parameters
The router retrieves the DSL line rate parameters from ANCP and reports this information
to the SRC software with the corresponding COPS messages. If the router cannot retrieve
the DSL line rate parameters from ANCP, it retrieves the DSL information in the following
ways:
•
From AAA layer —For PPP interfaces, the router retrieves the DSL line rate parameters
from the AAA layer and reports this information to the SRC software.
• From DHCP options —For DHCP external server and DHCP local server in equal-access
mode, the router retrieves the DSL line rate parameters from DHCP options and reports
this information to the SRC software. For more information about retrieval of DSL line
rate parameters from DHCP options, see DHCP Overview Information.
Learning the Partition ID from an Access Node
ANCP running on the network access server can learn the partition ID from an access
node and use this partition ID to communicate with the access node. This learning option
of the ANCP in the virtual router enables the network access server to learn the partition
IDs from all the access nodes. This learned partition ID can be used to send messages
to establish adjacency.
Platform Considerations
Configuring ANCP is supported on all E Series Broadband Services Routers.
For information about the modules supported on E Series routers:
•
See the ERX Module Guide for modules supported on ERX7xx models, ERX14xx models,
and the ERX310 Broadband Services Router.
• See the E120 and E320 Module Guide for modules supported on the E120 and E320
Broadband Services Routers.
187 Copyright © 2010, Juniper Networks, Inc.
Chapter 7: Configuring ANCP