IEEE802.16中上行带宽调度算法研究
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摘要
随着宽带无线通信技术的发展以及多媒体业务的广泛应用,用户要求宽带无线接入技术能够提供服务质量(QoS)保证。为了很好地满足未来宽带无线接入的应用需求,IEEE组织提出了802.16系列标准。IEEE802.16标准定义了物理层技术和媒体接入层(MAC层)机制,并且在MAC层划分了业务的调度类型,使不同类型的业务连接关联不同的QoS参数,从而提供了对业务QoS的支持。此外,协议中还给出了用于主动授权业务(UGS)的带宽调度方法,但是并没有对其它类型业务的具体调度算法以及系统的调度结构予以说明,这些都是带宽调度的重要部分,而带宽调度又是保证各类型业务QoS的关键。因此,对802.16系统中带宽调度结构及算法的研究具有十分重要的意义。
论文对现有的调度架构以及相关算法进行了深入的研究和分析。大部分算法关注的焦点都只是在保证业务的QoS要求方面,没有兼顾对系统调度服务公平性的考虑。为了在提供业务QoS保证的同时解决调度过程中服务不公平的问题,提出了一种基于预分配机制的带宽调度算法。该算法首先为高优先级业务预分配一部分带宽资源以保证其QoS对数据速率的要求,对带宽的剩余部分采用调整优先级的亏空公平队列算法在各业务之间再次进行分配,直到可用的带宽为零或者所有业务流都获得了足额的带宽为止。
为实现不同SS的各业务连接能够公平有效地使用上行带宽资源,设计了GPSS(Grant per Subscriber Station)方式下的系统带宽调度模型,其中在BS端加入了加权最大最小公平算法,在SS端采用了基于预分配机制的带宽调度算法。加权最大最小公平算法由于考虑了不同业务对QoS的不同要求,实现了带宽资源在各SS之间的公平分配。基于预分配机制的带宽调度算法在为高优先级业务提供QoS保证的同时,又使得低优先级业务也能获得一定的服务机会,从而在一定程度上解决了高优先级业务过多地占用带宽资源致使低优先级业务长期得不到带宽而“饿死”的问题。
基于GPSS方式的系统带宽调度模型由于融合了加权最大最小公平算法和基于预分配机制带宽调度算法,所以提高了SS带宽请求的服务率,虽然该策略使实时轮询业务(rtPS业务)的吞吐量和时延特性有局部性的损失,但是仍然保证了各类型业务的相应QoS要求,并且兼顾了对低优先级业务的带宽分配,很好地实现了从用户节点到业务的调度公平性。
With the development of broadband wireless communication technology and more and more applications of the multimedia services, broadband wireless access technology should have the ability to guarantee the quality of services (QoS) required by users. In order to meet the application requirements of broadband wireless access in the future, IEEE organization has proposed a series of 802.16 standards. In IEEE802.16 standards the technology adopted by physical layer and the mechanism of MAC are defined detailedly. To support the QoS, services are divided into different scheduling types according to their QoS characters, and various service connections are associated with different QoS parameters. Furthermore, the scheduling algorithm for unsolicited grant service (UGS) is defined, but the standard don't give explanation for scheduling structures and concrete scheduling algorithms for the other types of services. Therefore, studying on bandwidth scheduling structures and algorithms of 802.16 system has extremely vital significance.
The proposed scheduling architectures and algorithms are studied and analyzed in depth in the thesis. Most algorithms are just focus on the aspect of guaranteeing the QoS of services, but not giving considerations to the scheduling fairness of system. Thus a novel bandwidth scheduling algorithm based on pre-allocation mechanism is proposed to provide guarantee for the QoS of services and to resolve the problem of servicing unfair in the scheduling process. To make sure the request of data rate of high priority services, this algorithm will pre-allocate some bandwidth resource for them firstly. Then for the rest of bandwidth, the real time polling services, non-real time polling services and best effort services are allowed to share through the changed priority deficit queue algorithm. The scheduling will not be stopped until the usable bandwidths are zero or all service flows have got required bandwidths.
In order to realize that uplink bandwidths could be used fair and efficiently among various service connections which is belong to different SSs, a model of bandwidth scheduling based on Grant Per Subscriber Station (GPSS) mode is established. In this model, the weight max-min fair algorithm is introduced to base station, and the novel bandwidth scheduling algorithm based on pre-allocation mechanism is used by subscriber stations. Because it has considered that various services have different requirement for QoS, so the weight max-min fair algorithm could allocate bandwidths fairly among subscriber stations. The proposed novel algorithm makes the lower priority service flows obtain some service opportunities while the high priority service flows' QoS are guaranteed as well. From the above, we can see that it has the ability to resolve the problem that the lower priority service flows are starved because most bandwidths is occupied by the high priority service flows and little bandwidths could be provided to the lower priority service flows for a long time in a certain degree.
The weighted max-min fair scheduling algorithm and the bandwidth scheduling algorithm based on pre-allocate mechanism are embedded into the designed system model, so the service rate of the subscriber station's bandwidth requests could be raised. Although the throughput and delay characteristic of real-time polling services are lost in some cases, but it gives consideration to allocate bandwidths for the lower priority service flows, so it has achieved scheduling fairness well from user nodes to services.
论文对现有的调度架构以及相关算法进行了深入的研究和分析。大部分算法关注的焦点都只是在保证业务的QoS要求方面,没有兼顾对系统调度服务公平性的考虑。为了在提供业务QoS保证的同时解决调度过程中服务不公平的问题,提出了一种基于预分配机制的带宽调度算法。该算法首先为高优先级业务预分配一部分带宽资源以保证其QoS对数据速率的要求,对带宽的剩余部分采用调整优先级的亏空公平队列算法在各业务之间再次进行分配,直到可用的带宽为零或者所有业务流都获得了足额的带宽为止。
为实现不同SS的各业务连接能够公平有效地使用上行带宽资源,设计了GPSS(Grant per Subscriber Station)方式下的系统带宽调度模型,其中在BS端加入了加权最大最小公平算法,在SS端采用了基于预分配机制的带宽调度算法。加权最大最小公平算法由于考虑了不同业务对QoS的不同要求,实现了带宽资源在各SS之间的公平分配。基于预分配机制的带宽调度算法在为高优先级业务提供QoS保证的同时,又使得低优先级业务也能获得一定的服务机会,从而在一定程度上解决了高优先级业务过多地占用带宽资源致使低优先级业务长期得不到带宽而“饿死”的问题。
基于GPSS方式的系统带宽调度模型由于融合了加权最大最小公平算法和基于预分配机制带宽调度算法,所以提高了SS带宽请求的服务率,虽然该策略使实时轮询业务(rtPS业务)的吞吐量和时延特性有局部性的损失,但是仍然保证了各类型业务的相应QoS要求,并且兼顾了对低优先级业务的带宽分配,很好地实现了从用户节点到业务的调度公平性。
With the development of broadband wireless communication technology and more and more applications of the multimedia services, broadband wireless access technology should have the ability to guarantee the quality of services (QoS) required by users. In order to meet the application requirements of broadband wireless access in the future, IEEE organization has proposed a series of 802.16 standards. In IEEE802.16 standards the technology adopted by physical layer and the mechanism of MAC are defined detailedly. To support the QoS, services are divided into different scheduling types according to their QoS characters, and various service connections are associated with different QoS parameters. Furthermore, the scheduling algorithm for unsolicited grant service (UGS) is defined, but the standard don't give explanation for scheduling structures and concrete scheduling algorithms for the other types of services. Therefore, studying on bandwidth scheduling structures and algorithms of 802.16 system has extremely vital significance.
The proposed scheduling architectures and algorithms are studied and analyzed in depth in the thesis. Most algorithms are just focus on the aspect of guaranteeing the QoS of services, but not giving considerations to the scheduling fairness of system. Thus a novel bandwidth scheduling algorithm based on pre-allocation mechanism is proposed to provide guarantee for the QoS of services and to resolve the problem of servicing unfair in the scheduling process. To make sure the request of data rate of high priority services, this algorithm will pre-allocate some bandwidth resource for them firstly. Then for the rest of bandwidth, the real time polling services, non-real time polling services and best effort services are allowed to share through the changed priority deficit queue algorithm. The scheduling will not be stopped until the usable bandwidths are zero or all service flows have got required bandwidths.
In order to realize that uplink bandwidths could be used fair and efficiently among various service connections which is belong to different SSs, a model of bandwidth scheduling based on Grant Per Subscriber Station (GPSS) mode is established. In this model, the weight max-min fair algorithm is introduced to base station, and the novel bandwidth scheduling algorithm based on pre-allocation mechanism is used by subscriber stations. Because it has considered that various services have different requirement for QoS, so the weight max-min fair algorithm could allocate bandwidths fairly among subscriber stations. The proposed novel algorithm makes the lower priority service flows obtain some service opportunities while the high priority service flows' QoS are guaranteed as well. From the above, we can see that it has the ability to resolve the problem that the lower priority service flows are starved because most bandwidths is occupied by the high priority service flows and little bandwidths could be provided to the lower priority service flows for a long time in a certain degree.
The weighted max-min fair scheduling algorithm and the bandwidth scheduling algorithm based on pre-allocate mechanism are embedded into the designed system model, so the service rate of the subscriber station's bandwidth requests could be raised. Although the throughput and delay characteristic of real-time polling services are lost in some cases, but it gives consideration to allocate bandwidths for the lower priority service flows, so it has achieved scheduling fairness well from user nodes to services.
引文
[1] IEEEStd802.16-2004, IEEE Standard for Local and metropolitan area networks Part 16: Air interface for fixed broadband wireless access systems. IEEE, 2004.
[2] IEEEStd802.16-2005, IEEE Standard for Local and metropolitan area networks Part 16: Air interface for fixed and mobile broadband wireless access systems. IEEE, 2005.
[3]朱琦,鄂广增. IEEE802.16标准[J].中兴通信技术, 2005,11(2):4-7.
[4]敖立.宽带接入技术的最新进展[J].电信课学, 2005,(3):26-30.
[5] Leila Pishdad, Hamid R.Rabiee, Nasim Mirarmandehi. A fair optimization scheduling scheme for IEEE 802.16 networks in multimedia applications[J]. Journal of Visual Communication and Image Representation, 2010,21(2):167-174.
[6] Donghong Chao, Junhong Song, Minsu Kim. Performance analysis of the IEEE 802.16 wireless metropolitan area network[J]. Proceeding of the First International Conference on Distributed Frameworks for multimedia Application, 2005:130-137.
[7] Guosong Chu, Deng Wang, Shunliang Mei. A QoS architecture for the MAC protocol of IEEE 802.16 BWA system[J]. IEEE 2002 International Conference on Communications Circuits and System and West Sino Expositions, 2002,1:435-439.
[8] Shyamal Ramachandran, Charles W.Bostian, Scott F.Midkiff. Performance evaluation of IEEE 802.16 for broadband wireless access [J]. Proc of OPNETWORK 2002, 2002:1-5.
[9] Spyros A.Xergias, Nikos Passas, Lazaros Merakos. Flexible resource allocation in IEEE 802.16 wireless metropolitan area networks[J]. IEEE Workshop on Local and Metropolitan Area Networks, 2005:1-6.
[10] Carl Eklund, Roger B.Marks, Kenneth L.Stanwood. IEEE Standard 802.16: A technical overview of the wireless MAN air interface for broadband wireless access[M]. IEEE Communication Magazine, 2002:100-107.
[11] Shouchi Lo, Yuanyung Hong. A novel QoS scheduling approach for IEEE 802.16 BWA systems[C]. 11th IEEE International Conference on Communication Technology, ICCT, 2008:46-49.
[12] Ishyan Hwang, Jhongyue Lee, Chihwei Huang. Advanced dynamic bandwidth allocation and scheduling scheme for the integrated architecture of EPON and WiMAX[C]. Tenth International Conference on Mobile Data Management: Systems, Services and Middleware, MDM'09, 2009:655-660.
[13] Hamed S Alavi, Mona Mojdeh, Nasser Yazdani. A quality of service architecture for IEEE802.16 standards[C]. Perth, Western Australia:Asia-Pacific Conference on Communications, 2005:249-253.
[14]董晓鲁,党梅梅,沈嘉,等. WiMAX技术、标准与应用[M].北京:人民邮电出版社, 2007. 56-115.
[15]彭木根,王文博.下一代宽带无线通信系统OFDM&WiMAX[M].北京:机械工业出版社, 2007. 337-358.
[16]曾春亮,张宁,王旭莹. WiMAX/802.16原理与应用[M].北京:机械工业出版社, 2007. 50-86.
[17]彭木根,李茗,王文博. WiMAX系统中QoS机制研究[J].中兴通讯技术, 2005,11(2):30-35.
[18]宋海波,谈振辉. 802.16宽带无线接入系统的QoS保证和调度策略[J].电信科学, 2005,21 (3):46-49.
[19] Hong Peng, Yun Hua. A bandwidth scheduling architecture for the MAC protocol of IEEE 802.16 BWA system[C]. 4th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM'08,2008:1-4.
[20]林闯,单志广,任丰原.计算机网络的服务质量(QoS)[M].北京:清华大学出版社, 2004.
[21] Alexander Sayenko, Olli Alanen, Juha Karhula. Ensuring the QoS requirements in 802.16 scheduling[J]. Proc 9th ACM International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems, 2006:108-117.
[22] Shreedhar M, George Varghese. Efficient fair queuing using deficit round robin[J]. Proc ACM SIGCOMM, 1995,25(4):231-242.
[23] Abhay K.Parekh, Robert G.Gallagher. A generalized processor sharing approach to flow control in integrated services networks: The multiple node case[J]. IEEE/ACM Trans. on Networking, 1994,2:137-150.
[24] David Chuck, Kuanyu Chen and J.Morris Chang. A comprehensive analysis of bandwidth request mechanisms in IEEE 802.16 networks[J]. IEEE Transactions on Vehicular Technology, 2010,PP(99):1-11.
[25] Jonny Sun, Yangli Yao, Hongfei Zhu. Quality of service scheduling for 802.16 broadband wireless access systems[J]. IEEE VTC-Spring, 2006,3:1221-1225.
[26]张丹,刘乃安.一种有效的802.16 MAC层QoS调度架构[J].电信快报, 2005,(8): 35-37.
[27] Andres Arcia Moret, Nicolas Montavont, Alejandro Paltrineri. Improving uplink bandwidth management in 802.16 networks[C]. IEEE 34th Conference on Local Computer Networks, LCN 2009, 2009:233-236.
[28] Kitti Wongthavarwat, Aura Ganz. Packet scheduling for QoS support in IEEE 802.16 broadband wireless access system in TDD mode[J]. International Journal of CommunicationSystems, 2003,16:81-96.
[29] Kitti Wongthavarwat, Aura Ganz. IEEE 802.16 based last mile broadband wireless military networks with quality of service support[C]. IEEE Military Communications Conference, MILCOM2003, 2003,2:779-784.
[30] Mohammed Hawa, David W.Petr. Quality of service scheduling in cable and broadband wireless Access systems[J]. Tenth IEEE International Workshop on Quality of service, 2002:247～255.
[31]李蕾,张晓敏.应用WFQ的分级分组调度算法[J].山东大学学报(工学版), 2002,32 (2):167-171.
[32]杨博,刘琰,刘乃安.一种分级WFQ的宽带无线接入系统QoS架构[J].中兴通信, 2005, 11(2):36-42.
[33] Jianfeng Chen, Wenhua Jiao, Hongxi Wang. A service flow management strategy for IEEE 802.16 broadband wireless access systems in TDD mode[C]. IEEE International Conference on Communications, 2005,5:16-20.
[34]陈永锐,粟欣,乐正友.基于预留的802.16MAC层资源调度算法[J].微电子学与计算机, 2008,25(1):62-65.
[35] Gang Zhang, Chungui Liu, Feng Wang. Quality of service scheduling based on GPSS in IEEE 802.16 WiMAX networks[C]. Wireless Communications, Networking and Mobile Computing, WiCOM '08 4th International Conference, 2008:1-4.
[36] Yaxin Cao, Victor O.K.Li. Scheduling algorithms in broadband network[J]. Proceedings of the IEEE, 2001:76-87.
[37]陈东. WIMAX系统的分组调度算法研究[D].西安电子科技大学硕士学位论文, 2008.
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[50] Juliana Freitag Borin, Nelson L.S da Fonseca. Uplink scheduler and admission control for the IEEE 802.16 standard[C]. IEEE GLOBECOM 2009 Global Telecommunications Conference, 2009:1-6.
[2] IEEEStd802.16-2005, IEEE Standard for Local and metropolitan area networks Part 16: Air interface for fixed and mobile broadband wireless access systems. IEEE, 2005.
[3]朱琦,鄂广增. IEEE802.16标准[J].中兴通信技术, 2005,11(2):4-7.
[4]敖立.宽带接入技术的最新进展[J].电信课学, 2005,(3):26-30.
[5] Leila Pishdad, Hamid R.Rabiee, Nasim Mirarmandehi. A fair optimization scheduling scheme for IEEE 802.16 networks in multimedia applications[J]. Journal of Visual Communication and Image Representation, 2010,21(2):167-174.
[6] Donghong Chao, Junhong Song, Minsu Kim. Performance analysis of the IEEE 802.16 wireless metropolitan area network[J]. Proceeding of the First International Conference on Distributed Frameworks for multimedia Application, 2005:130-137.
[7] Guosong Chu, Deng Wang, Shunliang Mei. A QoS architecture for the MAC protocol of IEEE 802.16 BWA system[J]. IEEE 2002 International Conference on Communications Circuits and System and West Sino Expositions, 2002,1:435-439.
[8] Shyamal Ramachandran, Charles W.Bostian, Scott F.Midkiff. Performance evaluation of IEEE 802.16 for broadband wireless access [J]. Proc of OPNETWORK 2002, 2002:1-5.
[9] Spyros A.Xergias, Nikos Passas, Lazaros Merakos. Flexible resource allocation in IEEE 802.16 wireless metropolitan area networks[J]. IEEE Workshop on Local and Metropolitan Area Networks, 2005:1-6.
[10] Carl Eklund, Roger B.Marks, Kenneth L.Stanwood. IEEE Standard 802.16: A technical overview of the wireless MAN air interface for broadband wireless access[M]. IEEE Communication Magazine, 2002:100-107.
[11] Shouchi Lo, Yuanyung Hong. A novel QoS scheduling approach for IEEE 802.16 BWA systems[C]. 11th IEEE International Conference on Communication Technology, ICCT, 2008:46-49.
[12] Ishyan Hwang, Jhongyue Lee, Chihwei Huang. Advanced dynamic bandwidth allocation and scheduling scheme for the integrated architecture of EPON and WiMAX[C]. Tenth International Conference on Mobile Data Management: Systems, Services and Middleware, MDM'09, 2009:655-660.
[13] Hamed S Alavi, Mona Mojdeh, Nasser Yazdani. A quality of service architecture for IEEE802.16 standards[C]. Perth, Western Australia:Asia-Pacific Conference on Communications, 2005:249-253.
[14]董晓鲁,党梅梅,沈嘉,等. WiMAX技术、标准与应用[M].北京:人民邮电出版社, 2007. 56-115.
[15]彭木根,王文博.下一代宽带无线通信系统OFDM&WiMAX[M].北京:机械工业出版社, 2007. 337-358.
[16]曾春亮,张宁,王旭莹. WiMAX/802.16原理与应用[M].北京:机械工业出版社, 2007. 50-86.
[17]彭木根,李茗,王文博. WiMAX系统中QoS机制研究[J].中兴通讯技术, 2005,11(2):30-35.
[18]宋海波,谈振辉. 802.16宽带无线接入系统的QoS保证和调度策略[J].电信科学, 2005,21 (3):46-49.
[19] Hong Peng, Yun Hua. A bandwidth scheduling architecture for the MAC protocol of IEEE 802.16 BWA system[C]. 4th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM'08,2008:1-4.
[20]林闯,单志广,任丰原.计算机网络的服务质量(QoS)[M].北京:清华大学出版社, 2004.
[21] Alexander Sayenko, Olli Alanen, Juha Karhula. Ensuring the QoS requirements in 802.16 scheduling[J]. Proc 9th ACM International Symposium on Modeling Analysis and Simulation of Wireless and Mobile Systems, 2006:108-117.
[22] Shreedhar M, George Varghese. Efficient fair queuing using deficit round robin[J]. Proc ACM SIGCOMM, 1995,25(4):231-242.
[23] Abhay K.Parekh, Robert G.Gallagher. A generalized processor sharing approach to flow control in integrated services networks: The multiple node case[J]. IEEE/ACM Trans. on Networking, 1994,2:137-150.
[24] David Chuck, Kuanyu Chen and J.Morris Chang. A comprehensive analysis of bandwidth request mechanisms in IEEE 802.16 networks[J]. IEEE Transactions on Vehicular Technology, 2010,PP(99):1-11.
[25] Jonny Sun, Yangli Yao, Hongfei Zhu. Quality of service scheduling for 802.16 broadband wireless access systems[J]. IEEE VTC-Spring, 2006,3:1221-1225.
[26]张丹,刘乃安.一种有效的802.16 MAC层QoS调度架构[J].电信快报, 2005,(8): 35-37.
[27] Andres Arcia Moret, Nicolas Montavont, Alejandro Paltrineri. Improving uplink bandwidth management in 802.16 networks[C]. IEEE 34th Conference on Local Computer Networks, LCN 2009, 2009:233-236.
[28] Kitti Wongthavarwat, Aura Ganz. Packet scheduling for QoS support in IEEE 802.16 broadband wireless access system in TDD mode[J]. International Journal of CommunicationSystems, 2003,16:81-96.
[29] Kitti Wongthavarwat, Aura Ganz. IEEE 802.16 based last mile broadband wireless military networks with quality of service support[C]. IEEE Military Communications Conference, MILCOM2003, 2003,2:779-784.
[30] Mohammed Hawa, David W.Petr. Quality of service scheduling in cable and broadband wireless Access systems[J]. Tenth IEEE International Workshop on Quality of service, 2002:247～255.
[31]李蕾,张晓敏.应用WFQ的分级分组调度算法[J].山东大学学报(工学版), 2002,32 (2):167-171.
[32]杨博,刘琰,刘乃安.一种分级WFQ的宽带无线接入系统QoS架构[J].中兴通信, 2005, 11(2):36-42.
[33] Jianfeng Chen, Wenhua Jiao, Hongxi Wang. A service flow management strategy for IEEE 802.16 broadband wireless access systems in TDD mode[C]. IEEE International Conference on Communications, 2005,5:16-20.
[34]陈永锐,粟欣,乐正友.基于预留的802.16MAC层资源调度算法[J].微电子学与计算机, 2008,25(1):62-65.
[35] Gang Zhang, Chungui Liu, Feng Wang. Quality of service scheduling based on GPSS in IEEE 802.16 WiMAX networks[C]. Wireless Communications, Networking and Mobile Computing, WiCOM '08 4th International Conference, 2008:1-4.
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