指導教授 : 吳和庭 博士 研究生： 簡睿毅 日期 : 2005 / 7 / 15

1. 乙太被動式光學網路上能支援多媒體服務之動態頻寬配置機制Dynamic Bandwidth Allocation Mechanisms for Multimedia Services on EPON 指導教授 : 吳和庭 博士 研究生：簡睿毅 日期 : 2005 / 7 / 15

2. Outline • Background • Passive Optical Network (PON) • Ethernet Passive Optical Network (EPON) • Multi-Point Control Protocol (MPCP) • Motivation • Dynamic Bandwidth Allocation Scheme • IPACT & DBAM • DBA with QoS • Simulation Result • Conclusion & Future Work

3. Background • The first mile still remains the bottleneck between high-capacity Local Area Networks (LANs) and the backbone network • A new technology is required to an end-user over a single network • Inexpensive , Simple , Scalable • Delivering bundled voice , data , video services

4. Passive Optical Network ( PON ) • A point-to-multipoint optical network • Two primary types of PON technologies • ATM PON • EPON

5. PON Topology

6. Ethernet Passive Optical Network • EPON started to be standardized by IEEE 802.3ah EFM since 2001(2004 July done) • Ethernet is a ubiquitous technology • Deployed widely in LAN, MAN and WAN • Ethernet is more attractive to PON than ATM • High speed - up to 10 Gigabit/s • Lower cost • Easier interoperability

7. EPON Architecture

8. Features of EPON • All data packets carried in EPON are encapsulated in Ethernet frames • Broadcasting in the downstream direction from the OLT to ONUs • Sharing the upstream channel capacity among ONUs That is the problem !

9. Multi-Point Control Protocol • The Multi-Point Control Protocol (MPCP) specifies a control mechanism between a Master unit and Slaves units connected to a Point-to-Multi-Point (P2MP) segment to allow efficient transmission of data • MPCP is implemented in MAC Control layer • MPCP uses five MAC Control messages • GATE, REPORT, REGISTER_REQ, REGISTER, and REGISTER_ACK

10. Motivation

11. Motivation • A dynamic bandwidth allocation scheme with a credit mechanism which can support QoS service and reduce packet delay

12. Dynamic Bandwidth Allocation Scheme • IPACT • Interleaved Polling with Adaptive Cycle Time • DBAM • Dynamic Bandwidth Allocation with Multiple Services • DBA with QoS • Dynamic Bandwidth Allocation with QoS

13. IPACT Operation Step (1/4)

14. IPACT Operation Step (2/4)

15. IPACT Operation Step (3/4)

16. IPACT Operation Step (4/4)

18. Definition (1) • EF • Expedited Forwarding，High Priority • AF • Assured Forwarding，Medium Priority • BE • Best Effort， Low Priority

19. Definition (2) • The maximum bandwidth parameter of a specific class of traffic is determined by the SLA between the end user and service provider • the amount of data queued up in the buffer • is the requested bandwidth for class c traffic • the estimation credit

20. Waiting Time & Cycle Time

21. DBAM Operation

22. DBAM Case Request Ri EF:60 AF:20 BE:20 SLA Si EF:20 AF:30 BE:50 Credit Ci EF:70 AF:25 BE:25 EF:20 AF:25 Assign Bandwidth = 100 EF:20 AF:25 BE:55

24. Definitions • Actual queue size when transmission start • Finally guarantee bandwidth

25. Waiting Time & Cycle Time

26. DBA with QoS Operation(1/2)

27. DBA with QoS Operation(2/2)

28. DBA with QoS Case Request Ri EF:60 AF:20 BE:20 SLA Si EF:20 AF:30 BE:50 Credit Ci EF:70 AF:25 BE:25 Actual Queue Request Ai EF:65 AF:30 BE:25 EF:20 AF:20 BE:20 Assign Bandwidth = 100 Gi EF:20 AF:20 BE:20

29. Gi EF:20 AF:25 BE:25 Request Ri EF:60 AF:20 BE:20 Gi EF:50 AF:25 BE:25 DBAM Gi EF:20 AF:25 BE:55

30. Simulation Model

31. Simulated Result (1)

32. Simulated Result (2)

33. Simulated Result (3)

34. Simulated Result (4)

35. Simulated Result (5)

36. Credit Consideration

37. Simulation Result (1)

38. Simulation Result (2)

39. Simulation Result (3)

40. Conclusion & Future Work • Proposed a dynamic bandwidth allocation scheme can support QoS and reduce the packet delay for Ethernet Passive Optical Network • Future Work : Credit consideration