Radius Interaction; Port Mapping - Cisco 10000 Series Configuration Manual

Chapter 1 Access-Network Control Protocol
Cisco IOS Release 12.2(28)ZV supports shaping for rate adaptive mode on the Cisco 10000 series router
Note
at the interface level only. The Cisco IOS Release 12.2(34)SB supports both Ethernet and Asynchronous
Tranfer Mode (ATM) as the medium for data transfer between the DSLAM and the broadband remote
access server.
A BRAS running ANCP listens for TCP requests from its ANCP neighbors (DSLAMs).
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Rate adaptive DSL uses signal quality to adjust line speeds. A BRAS typically sets the subscriber
interfaces to the maximum bandwidth agreed to in the service license agreement (SLA).
When customer premises equipment (CPE) is synchronized to a data rate that is lower than the line
speed, cell or packet loss occurs on the DSLAM. To prevent this, the DSLAM can use ANCP to notify
the BRAS of newly adjusted circuit rates.
When a customer-facing port:
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RADIUS Interaction

Interactions between the broadband remote access server and the RADIUS server are from the router to
RADIUS.
The BRAS sends the following attributes and attribute-value pairs (AVPs) to the RADIUS server:
ANCP Line Rates
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The BRAS uses Point-to-Point Protocol (PPPoE) to interact with the authentication, authorization, and
accounting (AAA) module. RADIUS processes the information and then takes appropriate action.

Port Mapping

Port mapping associates customer premises equipment (CPE) clients of a DSLAM with VLAN
subinterfaces on the BRAS. The VLANs include 802.1Q or queue-in-queue (Q-in-Q) hierarchical
VLANs. Port mapping is configured in global configuration mode on the BRAS by grouping CPE client
IDs with a specific DSLAM neighbor.
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After a TCP session is established—ANCP begins exchanging messages to establish neighborship
between the BRAS and its neighbors.
After neighborship is established—ANCP event messages can be sent from the DSLAM to the
BRAS.
Activates—The DSLAM sends a Port Up message to the BRAS. The appropriate quality of service
(QoS) takes effect in accordance with the ANCP-delivered information.
Deactivates—The DSLAM sends a Port Down message to the BRAS. ANCP reports the DSL state
sent by the DSLAM, which is typically Silent or Idle. If the broadband remote access server receives
another Port Up message, the subscriber sessions either time out or are renewed with a new shaping
rate. The shaping rate on the interface does not change until the router receives a new Port Up
message.
Upstream Data Rate
Attribute 197,
Ascend-Data-Rate
Attribute Type 38, Rx
Connect Speed AVP
Cisco 10000 Series Router Access Network Control Protocol Configuration Guide
Access-Network Control Protocol Description
Downstream Data Rate
Attribute 255,
Ascend-Xmit-Rate
Attribute Type 24, Tx
Connect Speed AVP
Output Policy Name
Attribute 77,
Connect-Speed-Info
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