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ANCP Applicability to PON draft-bitar-wadhwa-ancp-pon-00.txt Update on Differences from DSL. Nabil Bitar, Verizon Sanjay Wadhwa, Juniper Networks Francois LeFaucheur, Cisco. Outline. Drivers for ANCP in PON based Broadband Networks Use Cases
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ANCP Applicability to PON draft-bitar-wadhwa-ancp-pon-00.txtUpdate on Differences from DSL Nabil Bitar, Verizon Sanjay Wadhwa, Juniper Networks Francois LeFaucheur, Cisco IETF73 ANCP WG
Outline • Drivers for ANCP in PON based Broadband Networks • Use Cases • Main Differences from DSL case – multicast focus • Proposal IETF73 ANCP WG
Drivers for ANCP in PON based Broadband Networks • Tight coordination required between NAS and ANX to implement triple-play services with necessary QoE, including end-to-end bandwidth-optimized video delivery • Coordination also required between components of ANX (OLT and ONT) for optimized video delivery • Admission control over links on the data path between NAS and HGW (potential bottlenecks): NASOLT, OLTONT, ONTHGW • Synchronized multicast replication on NAS, OLT, and ONT • Interaction needs to be real-time as services are requested via network or application level signaling. IETF73 ANCP WG
Use Cases-Video Focus • Unified Video Resource Control • Multicast Admission Control • VoD Admission Control • Multicast Conditional Access • Access Topology Discovery – Not covered in this presentation • Remote Connectivity Check – Not covered in this presentation IETF73 ANCP WG
Unified Video Resource Control Option1: All control Centralized on NAS • Access and admission control for multicast performed by NAS. • IGMP is processed and terminated on the NAS. • Multicast replication distributed to ANX (ONT and OLT) under the control of NAS • NAS also participates in bandwidth-based admission control for VoD • triggered by VoD signaling + policy manager query • Or, admission request directly from video application server (not depicted in the following options reference diagrams) IETF73 ANCP WG
Unified Video Resource Control Option1: All control Centralized on NAS (cont.) • NAS performs video (unicast and multicast) bandwidth accounting • Bandwidth-based admission control takes into account the following constraints: • Subscriber Bandwidth • PON Bandwidth • OLT-NAS Link Bandwidth IETF73 ANCP WG
ONT HGW HGW NAS OLT ONT PON HGW ANCP Unified Video Resource Control Option1: All control Centralized on NAS (cont.) IGMP JOIN (S/*, G) Access Control & Subscriber B/W, PON B/W and OLT Link B/W based Admission Control ANCP Replication Start { <S/*,G>, Customer-Port-ID} ANCP Replication Start { <S/*,G>, Customer-Port-ID} Multicast Flow (S,G) on Multicast VLAN Multicast Flow (S,G) forwarded on unidirectional <Multicast GEM-PORT> on the PON by OLT. Multicast Flow (S,G) forwarded on Customer-Port by ONT/ONU. IETF73 ANCP WG
ONT HGW HGW NAS OLT ONT PON HGW ANCP Unified Video Resource Control Option1: All control Centralized on NAS (cont.) IGMP LEAVE (S/*, G) Admission Control <Resource Released> ANCP Replication Stop { <S/*,G>, Customer-Port-ID} ANCP Replication Stop { <S/*,G>, Customer-Port-ID} IETF73 ANCP WG
Unified Video Resource Control Option1: All control Centralized on NAS (cont.) Application Server HGW VoD Request Admission Request Admission Response ONT Policy Server Admission Request Admission Response HGW OLT ONU NAS PON HGW ANCP Subscriber B/W, PON B/W and OLT Link B/W based Admission Control IETF73 ANCP WG
Unified Video Resource Control Option2: Admission Control on NAS and ANX • ANX (OLT and ONT) snoops IGMP to create replication state. • ANX (OLT) performs bandwidth admission control on PON bandwidth. • NAS performs bandwidth admission control on subscriber bandwidth and OLT link bandwidth triggered by “admission requests” from ANX for multicast. • NAS interacts with OLT using ANCP (for PON bandwidth accounting) to perform admission control for VoD. IETF73 ANCP WG
Unified Video Resource Control Option2: Admission Control on NAS and ANX HGW NAS OLT ONT PON HGW ANCP IGMP JOIN (S/*, G) IGMP Snooping IGMP Snooping Admission-Request { Flow, Customer-Port-ID} Access Control Pass Access Control & PON B/W Admission Control Pass Admission-Request { Flow, Customer-Port-ID} Subscriber B/W & OLT Link BW Admission Control Admission-Reply-Pass { Flow, Customer-Port-ID} Update Replication State Admission-Reply-Pass { Flow, Customer-Port-ID} Update Replication State IETF73 ANCP WG
HGW NAS OLT ONU PON HGW ANCP Unified Video Resource Control Option2: Admission Control on NAS and ANX IGMP JOIN (S/*, G) IGMP Snooping IGMP Snooping Admission-Request { Flow, Customer-Port-ID} Access Control Access Control & PON B/W Admission Control Pass Admission-Request { Flow, Customer-Port-ID} Subscriber B/W & OLT Link BW Admission Control Fail Admission-Reply-Fail { Flow, Customer-Port-ID} Release PON B/W Update Replication State Admission-Reply-Fail { Flow, Customer-Port-ID} Remove Replication State IETF73 ANCP WG
Unified Video Resource Control Option2: Admission Control on NAS and ANX Application Server HGW VoD Request Admission Request Admission Response ONT Policy Server Admission Request Admission Response HGW OLT ONU NAS PON HGW ANCP Subscriber B/W and OLT Link B/W Admission Control Admission-Request { Bandwidth, Customer-Port-ID} PON B/W Admission Control Pass Admission-Response { Customer-Port-ID} IETF73 ANCP WG
Multicast Conditional Access • Two approaches for Network based Conditional Access: • Centralized on NAS. It could be triggered by “admission request” from ANX using ANCP or simply by IGMP. • Distributed to ANX (OLT and ONT). White and Black lists may be provisioned on OLT and ONT by NAS using ANCP. • Requests for groups in the Black list dropped closest to the subscriber (on the ONT). • Requests for groups which are not blocked by Black list can be propagated upstream towards OLT and NAS for bandwidth based admission control. IETF73 ANCP WG
Access Topology Discovery ONT HGW • NAS can discover DSL sync rate via ANCP for DSL local loops on a PON-fed Access Node (AN). • ONT (GPON Fed AN) can inform OLT of the DSL sync rate via ANCP. • OLT can inform NAS of the sync rate via ANCP • OLT can also inform NAS of the bandwidth on the OLT uplink to the NAS (this is relatively static, but NAS needs to always have an accurate picture of the available bandwidth on OLT uplink ). DSL1 HGW OLT GPON Fed AN NAS DSL2 PON HGW DSLn HGW ANCP ANCP IETF73 ANCP WG
Main Differences from DSL case Multicast Focus • Replication points: • PON: Three replication points – (1) NAS, (2) OLT, (3) ONT/ONU • xDSL: Two replication points – (1) NAS, (2) DSLAM • PON requires extension of replication control to one more point – the ONT • In Option1, from NAS to OLT to ONT • PON in the downstream direction between the OLT and ONT is a broadcast medium shared across users while in DSL the medium between the DSLAM and the ATU-R is dedicated per subscriber • In DSL, one can make bandwidth admission control based on NAS-DSLAM link available bandwidth, and available bandwidth per subscriber • In PON, one needs to make bandwidth admission control based on PON available bandwidth in addition to NAS-OLT and subscriber-available bandwidth as PON is shared across a set of subscribers • Require PON available bandwidth accounting across users sharing the same PON • Customer port ID includes port identification and PON bandwidth accounting on NAS(option1) • Or, distributed admission control between NAS (maintain subscriber and NAS-OLT) and OLT (maintain PON bandwidth accounting) (option 2) IETF73 ANCP WG
OMCI vs ANCP • OMCI is today the configuration control channel between the OLT and ONT in PON • OMCI does not require IP for ONT management • OMCI not designed for real-time transactions • ANCP • Applicable between OLT and ONT • requires communication over TCP/IP between OLT and ONT • Where the ONT does not support TCP/IP or is not reachable via IP, potentially the ANCP messages can be translated/communicated over OMCI for the purpose of multicast admission control and replication • OMCI is outside the scope of IETF and ANCP WG • If OMCI defines necessary extensions, ANCP-OMCI gateway function at the OLT may be defined IETF73 ANCP WG
Proposal • Framework: • Option1: Incorporate use-cases for ANCP as applicable to PON, and corresponding requirements for ANX and NAS, into the ANCP framework draft. • Option2: Keep use cases for ANCP as applicable to PON in a standalone document and evolve it as a WG document • Protocol: • Option 1: Add protocol extensions, and corresponding handling on ANX and NAS for the described use-cases to the protocol draft - preferred • Option 2: Define the deltas over protocol draft in a separate document and merge it later in protocol draft • Option 3: Define the deltas over protocol draft in a separate document and evolve it as standalone • Formulticast, identify PON port on OLT and customer port on ONT/ONU on which replication is to occur IETF73 ANCP WG
Questions/Discussion Thanks! IETF73 ANCP WG
PON Specific Terminology Passive Optical Network (PON) Composed of Optical Line Terminal (OLT). Optical Network Terminal (ONT), and splitters :Upstream (ONT to OLT):: TDM access Downstream (OLT to ONT): Point to Multipoint network in which unpowered splitters are used to split an optical signal on single optical fiber from OLT to multiple premises’ ONTs Access Node Complex (ANX) The Access Node (ANX) decomposed by two geographically distributed functions, performed by OLT and ONU/ONT. The general term Access Node (ANX) is used when describing functionality which doesn't depend on the physical location but rather on the "black box" behavior of OLT and ONU/ONT OLT (Optical Line Terminal) : Located in the Service provider's central office. Terminates and aggregates multiple PONs on the user side, and interfaces with the network service element (NAS) providing subscriber management. ONT (Optical Network Terminal) : terminates PON on the network side and provides PON adaptation. User-side interface and location dependent upon Network Deployment. IETF73 ANCP WG 21
PON Specific Terminology ONT (contd). FTTP : Fiber all the way to the premises. ONT has Ethernet (FE/GE) connectivity with HGW. In case of MDU, multi-subscriber ONU resides in basement or wiring closet and has FE/GE connectivity with each CPE. FTTC : Fiber terminated outside the premise. Last leg could be via xDSL (typically VDSL). OLT and ONT together referred to as “PON FED DSLAM”. PON-Customer-ID Identifier which uniquely identifies the ANX, and the access loop logical port to the customer premise. Logically composed of information containing identification of the OLT, the PON port on the OLT, the ONT, and the port on the ONT. IETF73 ANCP WG 22