Framework

1
Framework Requirementsfor an Access Node
Control Mechanism in Broadband Multi-Service
Networks
draft-ietf-ancp-framework-02.txt Presenter Dong
Sun
2
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

3
Outline

• ANCP concept
• Reference architecture
• Home Gateway, Access Node, Aggregation Network,
  NAS
• ANCP transport mechanisms
• ATM gt DSL Forum TR-059
• Ethernet gt DSL Forum TR-101
• Use cases
• Access Topology Discovery
• Access Loop Configuration
• Remote Connectivity Test
• Multicast
• ANCP requirements
• Network element requirements
• Access Node
• Network Access Server
• Management related requirements

4
Reference Architecture

--------
Policy
Server
--------


----- ----- --------
----- ---------- CPE --- HGW ---

----- ----- Access ---------
Regional
Node --- Aggreg. --- NAS --- Network
----- ----- Node
CPE --- HGW ---
---------
----- ----- --------
----- ----------
Information Reports
--------------------------gt
Control Requests
lt--------------------------
Control Responses
--------------------------gt  
Access Node Control
Mechanism
lt-------------------------gt
PPP, DHCP, IP lt---------gtlt-------
------------------------------gt
5
Use Case - Multicast
Updated text

• Resource efficient multicast gets increasingly
  important gt 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

6
Next steps

• Can we consider this draft as complete?
• No more outstanding comments from previous
  meetings
• Can we go to last call?

7

• Backup

8
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.

9
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)

10
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)

11
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

12
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/portvpi.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

13
Network Access Server requirements

• General Architecture
• 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/portvpi.vci)
• Message Handling
• Wholesale Model
• Communicate Access Loop Attributes to an LNS