1 / 30

EPON Introduction

EPON Introduction. Speaker : 尹培華 Pei- Hwa Yin 指導 教授：吳和庭老師. Outline. Introduction MPCP (Multi Point Control Protocol ) DBA introduction -IPACT ( Interleaved Polling with Adaptive Cycle Time ) -Priority Queuing Future work Reference.

caelan
Télécharger la présentation

EPON Introduction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. EPON Introduction Speaker :尹培華 Pei-Hwa Yin 指導教授：吳和庭老師

  2. Outline • Introduction • MPCP (Multi Point Control Protocol ) • DBA introduction -IPACT (Interleaved Polling with Adaptive Cycle Time ) -Priority Queuing • Future work • Reference

  3. Introduction Develop motivation : backbone bandwidth has experienced substantial growth , but little has changed in the access Network PON is one of solution to this problem due to -low cost -high bandwidth -easy to maintain

  4. Introduction PON : passive optical network - no active elements in the transmission path from source to destination Three basic components : a )OLT (optical line terminal) : - near service provider (control and modify bandwidth) - connect to the backbone network( ex : IP ) b )ONU (optical network unit) : - near end-users c )1:N passive star coupler(splitter or combiner) : - splitter(use in downstream direction) - combiner(use in upstream direction)

  5. Introduction Three common topology type a ) tree (use most) b ) bus c ) ring

  6. Introduction EPON : all data are encapsulated in Ethernet frames for transmission Feature : - long distance : 20 km - more cost effective - higher bandwidth : up to 10Gigabit/second Ethernet frame format

  7. Introduction Upstream direction : ONU->OLT : ONUs share the channel capacity /use TDMA mechanism that control by OLT Downstream direction : OLT->ONU : broadcasting

  8. MPCP(Multi Point Control protocol ) • a control mechanism between a Master and Slaves units connected to a Point-to-Multi-Point (P2MP) segment to allow efficient transmission of data - EPON use this protocol to transfer control message between OLT and ONU - It is a layer 2 protocol - Two mode a)normal mode – Bandwidth assignment / request b) Auto Discovery mode – Control Auto Discovery process

  9. MPCP(Multi Point Control protocol ) • Control message are as follows (defined by opcode field): -GATE -REPORT -REGISTER_REQ -REGISTER -REGISTER_ACK

  10. MPCP(Multi Point Control protocol ) Gate message format： Ps : flag=0/regular flag=1/discover

  11. MPCP(Multi Point Control protocol ) Gate message operation

  12. MPCP(Multi Point Control protocol ) Report messageformat：

  13. MPCP(Multi Point Control protocol ) Report message operation

  14. MPCP(Multi Point Control protocol ) Round Trip Time Measurement- Raging

  15. MPCP(Multi Point Control protocol ) Normal mode

  16. MPCP(Multi Point Control protocol ) Auto-discover mode Which are used to discover and register a newly connected ONU

  17. DBA framework DBA framework overview I

  18. DBA framework DBA framework overview II

  19. Inter-ONU Scheduling-IPACT Step 1 OLT throw Grant/request mechanism has already know the information that bandwidth allocation need and the information are store in a polling table , then OLT will send a message to notify the first ONU the time that can start to transmit data(include data size) Step 2 when ONU get message , it will start to transmit data in the end ,it will send another message to OLT ,to notify how many data that need to transmit next time Step 3 in a proper time OLT will send a grant message to the next ONU repeat 1~3 until end

  20. Inter-ONU Scheduling-IPACT EX:

  21. Inter-ONU Scheduling-IPACT If an ONU emptied its buffer completely, it will report 0 bytes back to the OLT. Correspondingly, in the next cycle the ONU will be granted 0 bytes, i.e., it will be allowed to send a new request, but no data. At the end of its transmission window, ONU will generate its own control message (Request) and send it Back to the OLT

  22. Inter-ONU Scheduling-IPACT Transmission window size -to notify how many data that OLT can send to a ONU Maximum transmission window : -to avoid ONUs with high traffic volumes monopolize the bandwidth Type -FIX -Limited -Gated -Constant Credited -Linear credit -Elastic

  23. Inter-ONU Scheduling-IPACT Max polling cycle time : If all ONU want to transmit data If only one ONU wants to transmit data

  24. Inter-ONU Scheduling-IPACT Fix : Limited : Gated : Constant credit

  25. Inter-ONU Scheduling-IPACT Linear Credit : Elastic :

  26. Intra-ONU scheduling- priority queuing Concept and feature : -Packets are classified by the system and then put in different priority queues - With in each of the priority queues , packet are scheduled as FIFO queue - Packet can scheduled if all higher priority queues are emptied limitation : Low priority queue may suffer starvation Benefits : Can provide simple QoS

  27. Intra-ONU scheduling- priority queuing

  28. Future work -Long reach PON -QoSbase of Dynamic Bandwidth Management in Integrated EPON and 802.16 Access Networks

  29. References [1] Glen Kramer , Davis BiswanathMukherjee, Gerry Pesavento ,Interleaved Polling with Adaptive Cycle Time (IPACT) A Dynamic Bandwidth Distribution Scheme in an. Optical Access Network,PhotonicNetwork Communications ,4 : 1 ,89-107, 2002 [2]N. Ghani, A. Shami, C. Assi, M. Y. A. Raja, Intra-ONU Bandwidth Scheduling in Ethernet Passive Optical Networks,IEEECOMMUNICATIONS LETTERS, VOL. 8, NO. 11, NOVEMBER 2004 [3] IEEE 802.3ah 2004 [4] RFC4837 – Managed Objects of Ethernet Passive Optical Networks ,July 2007

  30. Q&A

More Related