1. Performance Analysis of the IEEE 802.16 Wireless Metropolitan Area Network nmgmt.cs.nchu.edu.tw 系統暨網路管理實驗室 Systems & Network Management Lab Reporter ：黃文帥 2007/12/4 Proceeding of the First International Conference on Distributed Frameworks for Multimedia Applications (DFMA’05)

2. nmgmt.nchu.edu.tw 2 Outline Introduction 1 Proposed QoS Architecture 2 Simulation 3 Conclusion 4

3. nmgmt.nchu.edu.tw 3 Introduction Broadband Wireless Access  IEEE 802.16 Fast deployment. Cost saving. Support QoS.

4. nmgmt.nchu.edu.tw 4 Introduction Quality of Service  BWA systems are expected to support QoS for real time applications.  IEEE 802.16 standard doesn’t define the QoS based packet-scheduling algorithms.  This paper proposes an efficient QoS architecture, base on priority scheduling and dynamic bandwidth allocation.

5. nmgmt.nchu.edu.tw 5 Introduction Quality of Service  IEEE 802.16 defines four QoS services. Unsolicited Grant Service (UGS). Real-Time Polling Service (rtPS). Non-Real-Time Polling Service (nrtPS). Best Effort (BE).

6. nmgmt.nchu.edu.tw 6 Introduction Quality of Service

7. nmgmt.nchu.edu.tw 7 Introduction Quality of Service  IEEE 802.16 defines: The signaling mechanism for information exchange between BS and SS. The uplink scheduling for UGS service flow.  IEEE 802.16 doesn’t define: The uplink scheduling for rtPS, nrtPS, BE service flow. The admission control.

8. nmgmt.nchu.edu.tw 8 Proposed QoS Architecture Modification  At the BS: Add a detailed description of the Uplink Bandwidth Allocation Scheduling part. Admission Control part  At the SS: Add a traffic management module.

9. nmgmt.nchu.edu.tw 9 Proposed QoS Architecture Modification

10. nmgmt.nchu.edu.tw 10 Proposed QoS Architecture Connection establishment  Before establish connection: SS set connection request to BS. Admission control part of the BS decides to accept or reject. BS provide necessary information to SS.

11. nmgmt.nchu.edu.tw 11 Proposed QoS Architecture Connection establishment  After establish connection: Enforce the traffic on the contract. BS update the traffic management table. BS generate UL-MAP in downlink subframe. SS transmits packets according to the UL-MAP.

12. nmgmt.nchu.edu.tw 12 Proposed QoS Architecture Uplink Scheduler of SS  For rtPS connection, SS transmits UGS packet to append virtual packet arrival time of rtPS.  Data Packet Analysis Module (DPAM) can find the rtPS deadline information.  BS can determine order of Poll based on deadline information.

13. nmgmt.nchu.edu.tw 13 Proposed QoS Architecture Uplink Scheduler of SS  The nrtPS uses either contention-free or contention mode.  The BE uses only contention mode.

14. nmgmt.nchu.edu.tw 14 Proposed QoS Architecture Uplink Bandwidth Allocation Scheduling  DPAM of BS separates UGS data and virtual packets arrival time of rtPS.  Traffic Management Module manages the information to decide the Poll order of next time.

15. nmgmt.nchu.edu.tw 15 Proposed QoS Architecture Analytical model for channel utilization  Assume k classes of priority queues.  Arrival events are mutual independent.  Let C denote the server capacity and channel utilization for each class i.

16. nmgmt.nchu.edu.tw 16 Proposed QoS Architecture Analytical model for channel utilization  λ k is offered load for class k.  E[ τ k ] is the average service time for class k.

17. nmgmt.nchu.edu.tw 17 Simulation The simulation model  The system model consists one BS and numbers of SSs.  Several assumptions have been made to reduce the complexity of the simulation model. The effects of propagation delay are neglected. The channel is error-free. The BS has the ability to detect collision.

18. nmgmt.nchu.edu.tw 18 Simulation The simulation model

19. nmgmt.nchu.edu.tw 19 Simulation Results

20. nmgmt.nchu.edu.tw 20 Simulation Results

21. nmgmt.nchu.edu.tw 21 Conclusion  In this paper authors proposed a new QoS architecture for IEEE 802.16 BWA MAC protocol.  The simulation results show that architecture may provide QoS support for all type of traffic classes.