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Dynamic Bandwidth Quasi-reservation Scheme for Real-time Services in IEEE 802.16e Networks. Yin Ge,and Geng-Sheng Kuo IEEE Wireless Communications and Networking Conference, 2007.WCNC 2007. Outline. Introduction Related Content in IEEE 802.16e Standard The Dynamic Bandwidth Quasi-Reservation
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Dynamic Bandwidth Quasi-reservation Scheme for Real-time Services in IEEE 802.16e Networks Yin Ge,and Geng-Sheng Kuo IEEE Wireless Communications and Networking Conference, 2007.WCNC 2007
Outline • Introduction • Related Content in IEEE 802.16e Standard • The Dynamic Bandwidth Quasi-Reservation • Performance Simulation • Conclusion
Introduction • IEEE 802.16e standard did not specify any bandwidth reservation scheme that provides quality of service (QoS) support for real-time services • Handover • real-time services > non-real-time
IEEE 802.16e Standard • Two-phase activation model • Consideration for Handover • cannot be guaranteed to get the required bandwidth
Dynamic bandwidth quasi-reservation scheme (DBQRS) • based on • the handover probability • the traffic arrival probability • Provide QoS guarantee for real-time multimedia services
The probability of MS requiring BS to reserve bandwidth MS … MS 2 MS 1 Type 0 traffic Type 1 traffic SF 0 SF 1 SF 0 SF 1 SF 2 SF 3 SF 2 SF 3
The probability of MS requiring BS to reserve bandwidth handover and traffic arrival are independent
The probability of MS requiring BS to reserve bandwidth • Due to the different handover states as well as the diverse QoS requirements of traffics • Weighting coefficients αn • UGS • ERT-VR • RT-VR
Handover states • Weighting coefficients βk • βin : immigrate into the BS’s coverage area from the neighbor cells • βstay : stay in the BS’s coverage area • βout : move out of the serving BS’s coverage area • dynamic bandwidth quasi-reservation for MSs according
Admission Control Policy • Implemented a handover MS with active SFs enters the BS’s coverage, and a local MS issues new SFs • Real-time SFs arrive, non-real-time SFs must release the reserved bandwidth • By initiating DSC message to change the state of non-real-time SFs to be inactive
EX … Bfree MS Bandwidth Quasi-Bandwidth reservation
Performance Simulation • simulation model: OPNET Modeler • 7 hexagonal cells • 70 local MSs • 30 handover MSs per cell • evaluation on the central cell • weighting coefficients • α1=1 for UGS, α2=0.8 for RT-VR/ERT-VR • βin=1 for the incoming handover MSs, βstay=0.5 for the local MSs and βout=0.2 for the outgoing handover MSs
Conclusion • The proposed scheme not only provides QoS guarantee for real-time services, but also ensures the fairness of admitting handover and new real-time services • The proposed scheme achieves low NSBR and HSDR, low access delay for new real-time service as well as high system bandwidth utilization