Framework & Requirements for an Access Node Control Mechanism in Broadband Multi-Service Networks ANCP WG IETF 71 – Philadelphia draft-ietf-ancp-framework-05.txt Presenter: Stefaan De Cnodder

Main Updates in v05 Multicast use case reworked out per IETF discussion –Conditional Access –Admission Control –Accounting Time and volume accounting –Spontaneous Admission Response Updated corresponding Access Node and NAS requirements

Use Case – Multicast Conditional Access –White List: AN accepts locally –Black List: AN rejects locally –Grey List: AN queries the NAS for a decision –Algorithm when Join message is received: If multiple entries in one or more lists match, then entry with “most specific match” is selected If there are multiple “most specific match” entries: –Black list has precedence over Grey and White list –Grey list has precedence over White list If no match, then discard Join message –“catch-all” entries allowed E.g reject all messages: in black list

Use Case – Multicast Admission Control –Option 1: AN processes IGMP and queries the NAS for CAC decision Admission Request / Admission Response –Option 2: AN does not process IGMP; NAS performs CAC decision and instructs the AN All subscriber IGMP signaling is terminated on the NAS –Option 3: Policy Server queries the AN Either directly, or indirectly via the NAS Not addressed in this document

Use Case – Multicast Disabling Admission Control –Could be done by adding a “catch-all statement” for unknown streams in white list Any more specific match continues to take precedence over this entry, so this works only for “unknown streams” Should be marked as best-effort –Example use: accept Internet multicast streams that are offered as best effort traffic no need for CAC; Internet multicast will use remaining available best effort bandwidth

Use Case – Multicast Multicast Admission Control & white lists –When using white lists for guaranteed QoS content, CAC is required on the Access Node If not, grey list needs to be used instead CAC on the Access Node requires some means to provision bandwidth information on the Access Node –not addressed in this document –CAC for combined white/black/grey lists are not addressed in this document

Use Case – Multicast Accounting –Option 1: AN keeps track of when replication starts or stops, generates the time and/or volume accounting information and sends it to a central accounting system (no ANCP required) –Option 2: AN keeps track of when replication starts or stops and reports this to the NAS Basic accounting: Information Report when replication starts/ends Detailed accounting: Basic + traffic volume replicated

Use Case – Multicast Spontaneous Admission Response –NAS can dynamically stop the replication of a multicast flow NAS sends “Admission Response” to AN to terminate replication –NAS can control multicast replication when IGMP messages are not processed in the access network NAS receives no Admission Request messages

Next steps The authors propose to send draft-ietf-ancp-framework-05 to Last Call

Backup

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 October 2007:draft-ietf-ancp-framework-03.txt November 2007:draft-ietf-ancp-framework-04.txt February 2008:draft-ietf-ancp-framework-05.txt

Reference Architecture | Policy | | Server | | | CPE |---| HGW |---| | | | | | | Access | | | | Regional | | Node |---| Aggreg. |---| NAS |---| Network | | | | Node | | | | | | CPE |---| HGW |---| | | | | | Information Report / Admission Request > Admission Response / Control Request < Control Response > Access Node Control Mechanism PPP, DHCP, IP

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. Multicast flow –multicast Any Source Multicast group or multicast Source Specific Multicast (S,G) channel

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 Multicast Message Handling Parameter Control –Damping –Bundling Security

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/port:vpi.vci) Multicast Message Handling Wholesale Model –Communicate Access Loop Attributes to an LNS Security

Conditional Access - algorithm matches an entry in one of the lists Reject request “best match” applies to one list Apply decision associated with list - Black takes priority over Grey / White - Grey takes priority over White Find the “best match” entry YesNo YesNo Apply decision associated with list + precedence rule