基于MPLS的QoS机制研究及其实现
摘要
传统的IP网络是为了进行高效的数据传输而设计的,使用的TCP/IP协议族是一种无连接的、基于数据报的传输模式,提供的是“尽力而为”的服务,本身不具备QoS保障能力。随着实时业务和多媒体业务在网络中的应用不断增加,它们对网络服务质量的要求也日益增高,原有的IP QoS机制已经不能完全满足新业务对QoS的需求,因此,对QoS的实现机制展开研究已刻不容缓。本论文基于MPLS网络技术对解决QoS问题的相关技术进行了较深入地研究分析。
首先,论文对现有的QoS实现机制进行了分析,包括MPLS技术的工作原理及其相关技术,讨论比较了尽力而为、综合服务(IntServ)和区分服务(DiffServ)模型的优缺点,还讨论了IntServ和DiffServ模型相结合的网络模型以及在MPLS网络中实现IntServ和DiffServ模型的具体方案。区分服务感知的流量工程(DS-TE)技术将MPLS流量工程技术和DiffServ模型相结合,具有良好的可扩展性和有效的路由策略,是解决骨干网QoS的有效解决方案之一。
接着,本论文对DS-TE环境下的抢占机制进行了重点研究。针对V-PREPT算法存在的不足,给出了两种基于V-PREPT的改进算法:最优化带宽算法和ImprvN-V-PREPT算法。最优化带宽算法将避免带宽浪费放在首位,采用层层逼近的方法,提高了对带宽的约束程度,优化了在被抢占带宽方面的性能。ImprvN-V-PREPT算法,采用枚举方式,通过对所有能满足需求的LSP组合的抢占代价进行比较,选取具有最小代价的LSP组合。同时为了保证网络的稳定性,设定了能被抢占的LSP条数的阈值。通过MATLAB仿真比较,结果表明这两种改进算法比V-PREPT具有更好的性能。
然后,本论文还基于OPNET Modeler对MPLS TE和MPLS DiffServ技术进行了仿真,结果表明MPLS TE和MPLS DiffServ具有较好的QoS保证能力。同时提出了在MPLS VPN基础上实现MPLS DiffServ实验方案,测试结果表明MPLS DiffServ能有效保证高优先级业务的高服务质量要求,提高网络的QoS保证能力。
最后,对本文的工作进行了总结,并对下一步工作提出了展望。
Traditional IP network with the TCP/IP protocols, which base on datagram and are oriented-connectionless, is designed for efficient data transmission. It provides the type of Best-Effort service, so couldn't guarantee the QoS. With the increasing of real-time service and multi-media application in network, the requirement of QoS became stricter. The present QoS mechanism can't meet the need. So it's necessary to study the QoS mechanism. Based on MPLS technology, this thesis made a deep research on the related techniques which can solve the QoS problems.
Firstly, this thesis analyzed several major QoS mechanisms, including main principle and related techniques of MPLS, characteristics of Best-Effort, IntServ and DiffServ model, and comparison of their merits and demerits. The paper also investigated the solution of implementation of IntServ or DiffServ model in MPLS network. The DiffServ-aware traffic engineering combines the MPLS TE with DiffServ model, so is of good scalability and explicit route ability. There is nothing as good as DS-TE to work out the QoS problems of backbone network.
Secondly, this paper mainly studied the preemption mechanism in DS-TE model. According to defect of V-PREPT algorithm, the paper proposed two V-PREPT improved algorithms: Bandwidth Optimization and ImprvN-V-PRETP algorithm. The bandwidth optimization algorithm puts avoiding waste of bandwidth in the first place, uses hierarchical approximation method, which enhances restriction of bandwidth preemption, so optimizes the performance in the bandwidth preempted field. The ImprvN-V-PREPT algorithm enumerates all LSPs combination, and picks up the LSPs combination with the least cost. In order to ensure the network's stability, the maximum LSP preempted is set before preemption. By MATLAB simulation, these algorithms are proved that they both have better properties than V-PREPT.
Then this thesis simulated the MPLS TE and MPLS DiffServ with OPNET Modeler. It also put forward an experimental solution for realization of MPLS DiffServ in MPLS VPN network. The simulation result showed that MPLS TE has a good ability to optimize the distribution of bandwidth resource and MPLS DiffServ can satisfy traffics with high priority efficiently and improve the network's QoS.
Lastly, the paper summarized its study work and proposed a prospect of the nextwork.
首先,论文对现有的QoS实现机制进行了分析,包括MPLS技术的工作原理及其相关技术,讨论比较了尽力而为、综合服务(IntServ)和区分服务(DiffServ)模型的优缺点,还讨论了IntServ和DiffServ模型相结合的网络模型以及在MPLS网络中实现IntServ和DiffServ模型的具体方案。区分服务感知的流量工程(DS-TE)技术将MPLS流量工程技术和DiffServ模型相结合,具有良好的可扩展性和有效的路由策略,是解决骨干网QoS的有效解决方案之一。
接着,本论文对DS-TE环境下的抢占机制进行了重点研究。针对V-PREPT算法存在的不足,给出了两种基于V-PREPT的改进算法:最优化带宽算法和ImprvN-V-PREPT算法。最优化带宽算法将避免带宽浪费放在首位,采用层层逼近的方法,提高了对带宽的约束程度,优化了在被抢占带宽方面的性能。ImprvN-V-PREPT算法,采用枚举方式,通过对所有能满足需求的LSP组合的抢占代价进行比较,选取具有最小代价的LSP组合。同时为了保证网络的稳定性,设定了能被抢占的LSP条数的阈值。通过MATLAB仿真比较,结果表明这两种改进算法比V-PREPT具有更好的性能。
然后,本论文还基于OPNET Modeler对MPLS TE和MPLS DiffServ技术进行了仿真,结果表明MPLS TE和MPLS DiffServ具有较好的QoS保证能力。同时提出了在MPLS VPN基础上实现MPLS DiffServ实验方案,测试结果表明MPLS DiffServ能有效保证高优先级业务的高服务质量要求,提高网络的QoS保证能力。
最后,对本文的工作进行了总结,并对下一步工作提出了展望。
Traditional IP network with the TCP/IP protocols, which base on datagram and are oriented-connectionless, is designed for efficient data transmission. It provides the type of Best-Effort service, so couldn't guarantee the QoS. With the increasing of real-time service and multi-media application in network, the requirement of QoS became stricter. The present QoS mechanism can't meet the need. So it's necessary to study the QoS mechanism. Based on MPLS technology, this thesis made a deep research on the related techniques which can solve the QoS problems.
Firstly, this thesis analyzed several major QoS mechanisms, including main principle and related techniques of MPLS, characteristics of Best-Effort, IntServ and DiffServ model, and comparison of their merits and demerits. The paper also investigated the solution of implementation of IntServ or DiffServ model in MPLS network. The DiffServ-aware traffic engineering combines the MPLS TE with DiffServ model, so is of good scalability and explicit route ability. There is nothing as good as DS-TE to work out the QoS problems of backbone network.
Secondly, this paper mainly studied the preemption mechanism in DS-TE model. According to defect of V-PREPT algorithm, the paper proposed two V-PREPT improved algorithms: Bandwidth Optimization and ImprvN-V-PRETP algorithm. The bandwidth optimization algorithm puts avoiding waste of bandwidth in the first place, uses hierarchical approximation method, which enhances restriction of bandwidth preemption, so optimizes the performance in the bandwidth preempted field. The ImprvN-V-PREPT algorithm enumerates all LSPs combination, and picks up the LSPs combination with the least cost. In order to ensure the network's stability, the maximum LSP preempted is set before preemption. By MATLAB simulation, these algorithms are proved that they both have better properties than V-PREPT.
Then this thesis simulated the MPLS TE and MPLS DiffServ with OPNET Modeler. It also put forward an experimental solution for realization of MPLS DiffServ in MPLS VPN network. The simulation result showed that MPLS TE has a good ability to optimize the distribution of bandwidth resource and MPLS DiffServ can satisfy traffics with high priority efficiently and improve the network's QoS.
Lastly, the paper summarized its study work and proposed a prospect of the nextwork.
引文
[1]彭晖等.新型的骨干网路由平台-MPLS[M].北京:人民邮电出版社,2002.
[2]石晶林,丁炜等.MPLS宽带网络互联技术[M].北京:人民邮电出版社,2001.
[3]Rosen E.,Viswanathan A.,and R.Callon.Multiprotocol Label Switching Architecture[J],RFC 3031,January 2001.
[4]吴靖.IP交换技术协议与体系结构[M].北京:机械工业出版社,1999.
[5]赵慧玲,张国宏.ATM、帧中继、IP技术与应用[M].北京:电子工业出版社,1999.
[6]http://www.itfensi.com/Network/atm/11708019782768.html.
[7]韦云凯.基IPSec的BGP_MPLS VPN的研究与设计[J].电子科技大学.2004.7
[8]吴江等主编.下一代的IP骨干网络技术——多协议标记交换[M].北京:人民邮电出版社.2001.1
[9]华为数据宽带,MPLS技术白皮书,2004.1
[10]钱德沛等主编.计算机网络实验教程[M].北京:高等教育出版社.2004.
[11]HM-045.QoS原理及配置.华为3Com培训中心.
[12]王维.基于MPLS的VPN利QoS问题的研究及应用[J].重庆工程大学.2006.5.
[13]曾颖等.BGP/MPLS VPN原理及技术探析[J].广东通信技术.2005.4
[14]Shenker S.,Partridge C.and R.Guerin.Specification of Guaranteed Quality of Service[J],RFC 2212,September 1997.
[15]Zheng Wang.Internet QoS:Architectures and Mechanisms for Quality of Service[J],Morgan Kaufmann Publishers,2001.
[16]Quality of service glossary of terms,QoS Forum,2002,http://www.gosfonmi.com.
[17]林闯,单志广、任丰原等.计算机网络的服务质量(QoS)[M].北京:清华大学出版社.2004.
[18]D.Clark,S.Shenker,and Xerox PARC.Integrated Services in the Internet Architecture:an Overview.IETF RFC 1633.June 1994.
[19]S.Blake,D.Black,M.Carlson,et al.An Architecture for Differentiated Services.IETF RFC 2475.December 1998.
[20]Santiago Alvarez,Deploying MPLS QoS ITD Technical Marketing.
[21]邹仕洪,王文东,程时端.MPLS VPN支持QoS的研究[J].计算机工程与应用.2003.5.9.
[22]D.Awudche,J.Malcolm,J.Agogbua,M.O'Dell and J.McManus.Requirements for Traffic Engineering Over MPLS[J],IETF RFC 2702,1999
[23]Xiao X,Harman A,Bailey B,Ni L.Traffic Engineering with MPLS in the Internet[J].IEEE Network magazine,2000,14(2):28-33
[23]Ghanwani A,Jamoussi B,et al.Traffic Engineering Standards in IP Networks using MPLS [J].IEEE Communications Magazine,1999,37(12):49-53
[24]Li T.MPLS and the Evolving Internet Architecture[J].IEEE Communications Magazine,1999,37(12):38-41
[25]Elwalid A,Jin C,Low S,Widjaja I.MATE:MPLS Adaptive Traffic Engineering[A].In:Proceedings of the IEEE INFOCOM 2001[C].Alaska:IEEE Communications Society Press,2001,1300-1309
[26]X.Xiao,A.Hannan,B.Bailey,and L.Ni.Traffic engineering with MPLS in the Internet[J].IEEE Network.14(2):28-33,March/April 2000.
[27]F.Le Faucheur,W.Lai.Requirement for Support of Differentiated Services-aware MPLS Traffic Engineering[S].IETF RFC 3564,July 2003
[28]Ina Minei.MPLS DiffServ-aware Traffic Engineering[R].White Paper.JunIPer Networks,Inc.2004.h.ttp://www.junlPer.net,4-25
[29]F.Le Faucheur,W.Lai.Maximum Allocation Bandwidth Constraints Model for DiffServ-aware MPLS Traffic Engineering[S].IETF RFC 4125,June 2005
[30]F.Le Faucheur.Russion Dolls Bandwidth Constraints Model for DiffServ-aware MPLS Traffic Engineering[S].IETF RFC 4127,June 2005
[31]马喆,刘孟仁,金亮.基于DiffServ流量工程的带宽限制机制[J].微计算机信息,2006,22(6-3):57-59.
[32]Andersson L,Swallow G.The Multiprotocol Label Switching(MPLS)Working Group decision on MPLS signaling protocols[S].IETF RFC 3468.February 2003.
[33]F.Le Faucheur.Protocol Extensions for Support of Diffserv-aware MPLS Traffic Engineering[S].IETF RFC 4124.June 2005.
[34]Adrian Farrel.Multiprotocol Label Switching Preemption.IETF Interact Draft,draft-farrel-mpls-preemption-01.txt,April 2004.
[35]Matthew R,Meyer,Jean-Philippe Vasseur,Denver Maddux,et al.MPLS Traffic Engineering Soft Preemption.IETF Internet Draft,draft-ietf-mpls-soft-preemption-06.txt,June 2005.
[36]Matthew R,Meyer,JP.Vasseur.MPLS Traffic Engineering Soft Preemption.IETF Internet Draft,draft-ietf-mpls-soft-preemption-10.txt,February 2008.
[37]J.de Oliveira,JP.Vasseur,L.Chen,et al.Label Switched Path(LSP)Preemption Policies for MPLS Traffic Engineering.IETF RFC 4829,April 2007.
[38]Jaudelice C de Oliveira,et al.LSP Preemption Policies for Diffserv-aware MPLS Traffic Engineering.IETF Internet Draft,draft-deoliveira-diff-te-preemption-00.txt,February 2003.
[39]Juan A.Garay and Inder S.Gopal.Call Preemption in Communication Network[J].Proceeding of Infocom'92,pp.1043-1050,1992.
[40]Mohammad Peyarvian,Ajay D.Kshernkalyani.Connection Preemption:Issues,Algorithms,and a Simulation Study[J].Proceeding of IEEE INFOCOM 97,1997,4(1):143-151
[41]Jaudelice C de Oliveira,C.Scoglio,I.F.Akyildiz and G.Uhl.New preemption policies for DiffServ-aware traffic engineering to minimize rerouting in MPLS networks.IEEE/ACM Trans.Network.12(2004)(4),pp.733-745.
[42]J.C.de Oliveira,C.Scoglio,et al.A New Preemption Policy for DiffServ-Aware Traffic Engineering to Minimize Rerouting[J].Proceeding of IEEE INFOCOM 2002,pp.695-704 2002.
[43]Iftekhar Ahmad,Joarder Kamruzzaman,et al.Revenue Aware Preemption Policy in Multimedia Communication Networks[J].Multimedia and Expo,2005.ICME 2005.IEEE International Conference,6-8 July 2005.Page(s):1374-1377
[44]Lau Chun Hau,Boon-Hee Soong,et al.Preemption Algorithm with Re-Routing to Minimize Service Disruption[J].Communication Systems,2004.ICCS 2004.Sept.2004.Page(s):521-525.
[45]Mingying Zhu,Xiaoming He,Wu Ye.Minimizing Preemption Cost for DiffServ-Aware MPLS Traffic Engineering.Communications and Networking in China,2006.ChinaCom'06.Oct.2006.Page(s):1-5.
[46]陈敏.OPNET网络仿真[M].北京:清华大学出版社,2004.
[47]王博文,张金文.OPNET Modeler与网络仿真[M].北京:人民有点出版社,2003.
[48]李馨,叶明.OPNET Modeler网络建模与仿真[M].西安:西安电子科技大学出版社,2006.
[49]OPNET Modeler tutorial.
[50]Quidway AR 28系列路由器技术手册.
[51]D-ITG manual.
[52]http://www.grid.unina.it/software/ITG/
[2]石晶林,丁炜等.MPLS宽带网络互联技术[M].北京:人民邮电出版社,2001.
[3]Rosen E.,Viswanathan A.,and R.Callon.Multiprotocol Label Switching Architecture[J],RFC 3031,January 2001.
[4]吴靖.IP交换技术协议与体系结构[M].北京:机械工业出版社,1999.
[5]赵慧玲,张国宏.ATM、帧中继、IP技术与应用[M].北京:电子工业出版社,1999.
[6]http://www.itfensi.com/Network/atm/11708019782768.html.
[7]韦云凯.基IPSec的BGP_MPLS VPN的研究与设计[J].电子科技大学.2004.7
[8]吴江等主编.下一代的IP骨干网络技术——多协议标记交换[M].北京:人民邮电出版社.2001.1
[9]华为数据宽带,MPLS技术白皮书,2004.1
[10]钱德沛等主编.计算机网络实验教程[M].北京:高等教育出版社.2004.
[11]HM-045.QoS原理及配置.华为3Com培训中心.
[12]王维.基于MPLS的VPN利QoS问题的研究及应用[J].重庆工程大学.2006.5.
[13]曾颖等.BGP/MPLS VPN原理及技术探析[J].广东通信技术.2005.4
[14]Shenker S.,Partridge C.and R.Guerin.Specification of Guaranteed Quality of Service[J],RFC 2212,September 1997.
[15]Zheng Wang.Internet QoS:Architectures and Mechanisms for Quality of Service[J],Morgan Kaufmann Publishers,2001.
[16]Quality of service glossary of terms,QoS Forum,2002,http://www.gosfonmi.com.
[17]林闯,单志广、任丰原等.计算机网络的服务质量(QoS)[M].北京:清华大学出版社.2004.
[18]D.Clark,S.Shenker,and Xerox PARC.Integrated Services in the Internet Architecture:an Overview.IETF RFC 1633.June 1994.
[19]S.Blake,D.Black,M.Carlson,et al.An Architecture for Differentiated Services.IETF RFC 2475.December 1998.
[20]Santiago Alvarez,Deploying MPLS QoS ITD Technical Marketing.
[21]邹仕洪,王文东,程时端.MPLS VPN支持QoS的研究[J].计算机工程与应用.2003.5.9.
[22]D.Awudche,J.Malcolm,J.Agogbua,M.O'Dell and J.McManus.Requirements for Traffic Engineering Over MPLS[J],IETF RFC 2702,1999
[23]Xiao X,Harman A,Bailey B,Ni L.Traffic Engineering with MPLS in the Internet[J].IEEE Network magazine,2000,14(2):28-33
[23]Ghanwani A,Jamoussi B,et al.Traffic Engineering Standards in IP Networks using MPLS [J].IEEE Communications Magazine,1999,37(12):49-53
[24]Li T.MPLS and the Evolving Internet Architecture[J].IEEE Communications Magazine,1999,37(12):38-41
[25]Elwalid A,Jin C,Low S,Widjaja I.MATE:MPLS Adaptive Traffic Engineering[A].In:Proceedings of the IEEE INFOCOM 2001[C].Alaska:IEEE Communications Society Press,2001,1300-1309
[26]X.Xiao,A.Hannan,B.Bailey,and L.Ni.Traffic engineering with MPLS in the Internet[J].IEEE Network.14(2):28-33,March/April 2000.
[27]F.Le Faucheur,W.Lai.Requirement for Support of Differentiated Services-aware MPLS Traffic Engineering[S].IETF RFC 3564,July 2003
[28]Ina Minei.MPLS DiffServ-aware Traffic Engineering[R].White Paper.JunIPer Networks,Inc.2004.h.ttp://www.junlPer.net,4-25
[29]F.Le Faucheur,W.Lai.Maximum Allocation Bandwidth Constraints Model for DiffServ-aware MPLS Traffic Engineering[S].IETF RFC 4125,June 2005
[30]F.Le Faucheur.Russion Dolls Bandwidth Constraints Model for DiffServ-aware MPLS Traffic Engineering[S].IETF RFC 4127,June 2005
[31]马喆,刘孟仁,金亮.基于DiffServ流量工程的带宽限制机制[J].微计算机信息,2006,22(6-3):57-59.
[32]Andersson L,Swallow G.The Multiprotocol Label Switching(MPLS)Working Group decision on MPLS signaling protocols[S].IETF RFC 3468.February 2003.
[33]F.Le Faucheur.Protocol Extensions for Support of Diffserv-aware MPLS Traffic Engineering[S].IETF RFC 4124.June 2005.
[34]Adrian Farrel.Multiprotocol Label Switching Preemption.IETF Interact Draft,draft-farrel-mpls-preemption-01.txt,April 2004.
[35]Matthew R,Meyer,Jean-Philippe Vasseur,Denver Maddux,et al.MPLS Traffic Engineering Soft Preemption.IETF Internet Draft,draft-ietf-mpls-soft-preemption-06.txt,June 2005.
[36]Matthew R,Meyer,JP.Vasseur.MPLS Traffic Engineering Soft Preemption.IETF Internet Draft,draft-ietf-mpls-soft-preemption-10.txt,February 2008.
[37]J.de Oliveira,JP.Vasseur,L.Chen,et al.Label Switched Path(LSP)Preemption Policies for MPLS Traffic Engineering.IETF RFC 4829,April 2007.
[38]Jaudelice C de Oliveira,et al.LSP Preemption Policies for Diffserv-aware MPLS Traffic Engineering.IETF Internet Draft,draft-deoliveira-diff-te-preemption-00.txt,February 2003.
[39]Juan A.Garay and Inder S.Gopal.Call Preemption in Communication Network[J].Proceeding of Infocom'92,pp.1043-1050,1992.
[40]Mohammad Peyarvian,Ajay D.Kshernkalyani.Connection Preemption:Issues,Algorithms,and a Simulation Study[J].Proceeding of IEEE INFOCOM 97,1997,4(1):143-151
[41]Jaudelice C de Oliveira,C.Scoglio,I.F.Akyildiz and G.Uhl.New preemption policies for DiffServ-aware traffic engineering to minimize rerouting in MPLS networks.IEEE/ACM Trans.Network.12(2004)(4),pp.733-745.
[42]J.C.de Oliveira,C.Scoglio,et al.A New Preemption Policy for DiffServ-Aware Traffic Engineering to Minimize Rerouting[J].Proceeding of IEEE INFOCOM 2002,pp.695-704 2002.
[43]Iftekhar Ahmad,Joarder Kamruzzaman,et al.Revenue Aware Preemption Policy in Multimedia Communication Networks[J].Multimedia and Expo,2005.ICME 2005.IEEE International Conference,6-8 July 2005.Page(s):1374-1377
[44]Lau Chun Hau,Boon-Hee Soong,et al.Preemption Algorithm with Re-Routing to Minimize Service Disruption[J].Communication Systems,2004.ICCS 2004.Sept.2004.Page(s):521-525.
[45]Mingying Zhu,Xiaoming He,Wu Ye.Minimizing Preemption Cost for DiffServ-Aware MPLS Traffic Engineering.Communications and Networking in China,2006.ChinaCom'06.Oct.2006.Page(s):1-5.
[46]陈敏.OPNET网络仿真[M].北京:清华大学出版社,2004.
[47]王博文,张金文.OPNET Modeler与网络仿真[M].北京:人民有点出版社,2003.
[48]李馨,叶明.OPNET Modeler网络建模与仿真[M].西安:西安电子科技大学出版社,2006.
[49]OPNET Modeler tutorial.
[50]Quidway AR 28系列路由器技术手册.
[51]D-ITG manual.
[52]http://www.grid.unina.it/software/ITG/