Transcript ANCP - IETF

Framework & Requirements
for an Access Node Control Mechanism in
Broadband Multi-Service Networks
draft-ietf-ancp-framework-02.txt
Presenter: Dong Sun
History
• Jan 2006: draft-ooghe-l2cp-framework-00.txt submitted
for L2CP BOF
• May 2006: draft-ooghe-ancp-framework-00.txt
• November 2006: draft-ietf-ancp-framework-00.txt
• March 2007: draft-ietf-ancp-framework-01.txt
• July 2007: draft-ietf-ancp-framework-02.txt
– Updated multicast section
– Refer to draft-moustafa-ancp-security-threats for security
requirements
– Made network elements requirements informative
– Miscellaneous edits per comments on ANCP exploder
Outline
•
•
ANCP concept
Reference architecture
– Home Gateway, Access Node, Aggregation Network, NAS
•
ANCP transport mechanisms
– ATM => DSL Forum TR-059
– Ethernet => DSL Forum TR-101
•
Use cases
–
–
–
–
•
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Access Topology Discovery
Access Loop Configuration
Remote Connectivity Test
Multicast
ANCP requirements
Network element requirements
– Access Node
– Network Access Server
•
Management related requirements
Reference Architecture
+--------+
| Policy |
| Server |
+--------+
|
|
+-----+
+-----+
+--------+
+-----+
+----------+
| CPE |---| HGW |---|
|
|
|
|
|
+-----+
+-----+
| Access |
+---------+
|
|
| Regional |
| Node |---| Aggreg. |---| NAS |---| Network |
+-----+
+-----+
|
|
| Node
|
|
|
|
|
| CPE |---| HGW |---|
|
+---------+
|
|
|
|
+-----+
+-----+
+--------+
+-----+
+----------+
Information Reports
-------------------------->
Control Requests
<-------------------------Control Responses
-------------------------->
Access Node Control Mechanism
<------------------------->
PPP, DHCP, IP
<---------><------------------------------------->
Updated text
Use Case - Multicast
• Resource efficient multicast gets increasingly important =>
local replication!
• In order to ensure backward compatibility with the ATM
access model, the NAS, aggregation node and Access
Node need to behave as a single logical device
– This device must have the same functionality as the NAS in the
ATM access/aggregation network
• Actual implementation of the multicast behavior between
AN and NAS not detailed in the framework
– Behavior of logical device could be implemented in several ways
Next steps
• Can we consider this draft as complete?
– No more outstanding comments from previous meetings
• Can we go to last call?
Backup
Terminology
• Line Rate
– total data rate including overhead
• Net Data Rate
– portion of the total data rate that can be used to transmit user information
(e.g. ATM cells or Ethernet frames). It excludes overhead that pertains to
the physical transmission mechanism (e.g. trellis coding in case of DSL)
• Control Channel
– a bidirectional IP communication interface between the controller function
(in the NAS) and the reporting/enforcement function (in the AN)
• Access Node Control Adjacency
– relationship between an Access Node and a NAS for the purpose of
exchanging ANCP messages. The adjacency may either be up or down,
depending on the result of the Access Node Control Adjacency protocol
operation.
Use Case - Dynamic Access Loop
Attributes
• Communicating Access Loop attributes
– Beneficial since the Access Loop rate may change overtime
• NAS gains knowledge about the topology of the access
network (e.g. for QoS scheduling)
Use Case - Access Loop Configuration
• Change Access Loop parameters (e.g. rate) from the NAS
– Avoids cross-organization business-to-business interactions
– Allows to centralize Subscriber-related service data in e.g. a policy
server
• The best way to change Access Loop parameters is by
using profiles
– pre-configured on the Access Node using EMS
• Mechanism could be used for additional parameters (e.g.
QoS)
Use Case – Remote Connectivity Test
• NAS can use ANCP to initiate an Access Loop test
between Access Node and HGW
– Allows mixed ATM/Ethernet environment
– Supports multiple Access Loop technologies (e.g. ATM/ADSL,
Ethernet/VDSL)
• Preserve existing operational functionality
Access Node requirements
• General Architecture
– Partitioning
– Redundant controllers
• Control Channel Attributes
• Capability Negotiation Failure
• Adjacency Status Reporting
– Adjacency protocol
• Identification
– In line with TR-101 (e.g. Access-Node-Identifier atm slot/port:vpi.vci)
– The AN MUST use the same ACI format for identifying the AN and
access port in ANCP, PPPoE and DHCP messages
• Message Handling
• Parameter Control
– Damping
– Bundling
Network Access Server requirements
• General Architecture
–
–
–
–
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•
•
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Partitioning
Shaping based on Dynamic Access Loop Attributes
Access Loop Configuration
Remote Connectivity Test
Control Channel Attributes
Capability Negotiation Failure
Adjacency Status Reporting
Identification
– In line with TR-101 (e.g. Access-Node-Identifier atm slot/port:vpi.vci)
• Message Handling
• Wholesale Model
– Communicate Access Loop Attributes to an LNS