1. Broadband Mobile Wireless Network Lab Quality of Service Scheduling for 802.16 Broadband Wireless Access Systems Vehicular Technology Conference, 2006. VTC 2006-Spring. IEEE 63rd Jonny SUN, Yanling YAO, Hongfei ZHU Advanced System Technology Telecom Lab (Beijing) STMicroelectronics Beijing CHINA Presenter ： Pao-Wei Hwang 2015/12/21 1

2. Abstract  IEEE 802.16  support heterogeneous classes of traffic with differentiated Quality of Service (QoS).  In this paper, a new and efficient QoS scheduling strategy based on the hierarchical and distributed architecture is proposed for 802.16 Broadband Wireless Access (BWA) systems. 2015/12/21 2

3. Outline 2015/12/21 3 I. INTRODUCTION II. IEEE 802.16 BWA SYSTEMS III. QoS SCHEDULING FOR 802.16 SYSTEMS IV. SIMULATION MODEL AND RESULT ANALYSIS V. CONCLUSION

4. I. INTRODUCTION  Medium Access Control (MAC)  bandwidth allocation mechanisms UGS : Constant Bit Rate ( CBR ) real-time : Variable Bit Rate ( VBR ) Nonreal-time : Nonreal-time VBR Best Effort  MAC protocol does not include a complete solution for how to efficiently schedule traffic to fulfill the QoS requirements. 2015/12/21 4

5. II. IEEE 802.16 BWA SYSTEMS  IEEE 802.16d  point-to-multipoint (PMP) In downlink, from BS to SS –BS is the unique transmitter broadcasting to all the SSs In uplink,from SS to BS –BS is shared by all the SSs on a demand basis.  Mesh 2015/12/21 5

6. III. QoS SCHEDULING FOR 802.16 SYSTEMS  how to efficiently schedule different types?  propose a QoS scheduling strategy based on the hierarchical and distributed architecture. A. QoS Scheduling Architecture for 802.16 Systems B. Scheduling Algorithm at BS C. Scheduling Algorithm at SS 2015/12/21 6

7. III. QoS SCHEDULING FOR 802.16 SYSTEMS  B. Scheduling Algorithm at BS  Define two types of queue  Type (I) queue  Type(II) queue 2015/12/21 7  A. QoS Scheduling Architecture for 802.16 Systems

8.  Type I queue  UGS Guarantee grants to be scheduled without interrupt First-in First-out (FIFO) III. QoS SCHEDULING FOR 802.16 SYSTEMS TType I I queue rrtPS ， nrtPS ， and BE ffair queuing algorithm that consists of two phases: mminimum reserved bandwidth assurance eexcess bandwidth distribution. 2015/12/21 8

9. III. QoS SCHEDULING FOR 802.16 SYSTEMS  Fairness to distributing excess bandwidth 2015/12/21 9

10. III. QoS SCHEDULING FOR 802.16 SYSTEMS  C. Scheduling Algorithm at SS  Scheduling algorithm for UGS queues  Scheduling algorithm for rtPS queues  Scheduling algorithm for nrtPS queues  Scheduling algorithm for BE queues  At SS Priority of scheduling service 2015/12/21 10

11. III. QoS SCHEDULING FOR 802.16 SYSTEMS  Scheduling algorithm for UGS queues  Critical delay  Critical delay jitter  Firstly guarantee the bandwidth  Scheduling algorithm for rtPS queues  Should meet tight delay bound  Each packet of rtPS should be mark a deadline stamp 2015/12/21 11

12. III. QoS SCHEDULING FOR 802.16 SYSTEMS  Scheduling algorithm for nrtPS queues  Target at maintaining throughput  Each packet with a virtual time stamp  Scheduling algorithm for BE queues  There is no QoS guarantee required  A simple FIFO mechanisms is applied 2015/12/21 12

13. IV. SIMULATION MODEL AND RESULT ANALYSIS  NS2  PMP MAC operation  TDD-OFDM  One BS and 20 SSs 2015/12/21 13 SS UGSrtPSnrtPSBE First 1111 Second 1111 Third 1 Fourth 1 Fifth 1 Other 1

14. IV. SIMULATION MODEL AND RESULT ANALYSIS 2015/12/21 14

15. V. CONCLUSION  A new and efficient QoS scheduling strategy based on the hierarchical and distributed architecture is proposed to provide differentiated level of QoS guarantees to various application.  BS scheduler  Guarantee the minimum bandwidth for each service flow  SS scheduler  provide differentiated and flexible QoS support for all of the four scheduling service types 2015/12/21 15