基于在线双向拍卖的虚拟网络切片资源调度机制

为解决 5G网络切片间资源分配的问题,该文提出一种基于在线双向拍卖 (ODA)的资源调度机制。该机制首先针对不同的业务需求和业务收益确定网络切片的优先级和单位资源报价;其次明确最大化网络收益的目标建立线下单向拍卖模型;进一步,考虑资源的动态分配和回收利用,提出价格更新算法实时更新资源价格;最后,综合线下单向拍卖机制和价格动态变化机制建立在线双向拍卖模型,为切片动态分配资源。仿真结果表明,该机制在提高网络收益的同时可以保证各切片用户的QoS需求。     

面向智能化切片的服务化等级保障技术增强和研究

网络切片是5G垂直行业应用的重要使能技术,可以为不同应用场景提供差异化服务,切片服务等级保障使得运营商能够准确感知和评估各类业务的服务质量,以便进行服务质量的保障,然而,在切片的应用中,由于缺乏关于业务体验的实时监控,使运营商无法有效评估各类业务的服务质量。为了让运营商可以有效地评估各类业务的服务质量,首先利用网络数据分析功能分析得到切片中某个业务的用户体验,然后借助人工智能技术,基于业务体验数据建立业务模型,评估整个切片在运行态的切片SLA,从而更新切片的资源配置和调度,实现SLA的增强。     

小卫星业务调度路由优化

针对小卫星通信链路交换频繁和低资源利用率的问题，提出了一种基于调度的小卫星路由优化策略。建立起小卫星星座模型，根据其运行方向(与赤道平面近似垂直)和所在维度确定链路的实时连接策略，优化其路由路径。面对持续增长的网络业务与有限的星上资源的矛盾，将业务数据包分类为实时性数据包和非实时性数据包，实行加权轮询调度保证其服务质量和资源的利用率。仿真结果证明，相比已有小卫星路由算法，优化的路由算法可以有效减小数据传输时延并增加系统吞吐量。     

TWDM-PON中带有业务区分的混合资源调度算法

针对时分波分复用无源光网络长距离和广覆盖特性带来往返时延增大,造成高优先级业务时延性能严重恶化的问题,提出带有业务区分的混合资源调度算法.根据网络负载实时调整光网络单元组的波长数以实现资源共享,并动态划分子周期以对不同优先级业务进行区分服务;设计混合资源调度算法,以在线方式填充波长空隙,以离线方式保障资源高效调度.仿真结果表明,所提算法能够满足不同优先级业务的时延要求,保证服务质量,并提高信道利用率.     

H-CRAN网络下联合拥塞控制和资源分配的网络切片动态资源调度策略

针对异构云无线接入网络(H-CRAN)网络下基于网络切片的在线无线资源动态优化问题,该文通过综合考虑业务接入控制、拥塞控制、资源分配和复用,建立一个以最大化网络平均和吞吐量为目标,受限于基站(BS)发射功率、系统稳定性、不同切片的服务质量(QoS)需求和资源分配等约束的随机优化模型,并进而提出了一种联合拥塞控制和资源分配的网络切片动态资源调度算法。该算法会在每个资源调度时隙内动态地为性能需求各异的网络切片中的用户分配资源。仿真结果表明,该文算法能在满足各切片用户QoS需求和维持网络稳定的基础上,提升网络整体吞吐量,并且还可通过调整控制参量的取值实现时延和吞吐量间的动态平衡。     

一种新的支持多业务的CDMA网络可升降级动态带宽分配与优化策略

未来无线通信网络的主要发展方向是支持多种业务.在3GPP对UMTS的规范中,将业务按其属性对服务质量(Quality of Service,QoS)要求的不同分为4类:会话类、流媒体类、交互类和背景类,除话音业务外其余3种业务都是可变比特速率业务.对该网络用户资源分配(主要是带宽的分配)若采用传统的固定分配方法,必定陷入资源利用率低下和用户QoS得不到保障的两难境地.本文针对宽带CDMA网络,提出了一种针对无线多媒体业务的动态带宽分配与优化策略,在保证用户QoS的前提下,尽可能提高资源利用率.仿真结果表明,对比传统的网络资源管理策略,该策略大大改善了系统的性能,提高了系统资源利用率.     

动态控制MBMS速率提高移动网络利用率

文中提出了两种通过动态控制MBMS(多媒体广播及组播)业务速率以提高网络利用率的方法.现有的MBMS业务都只能通过分配固定空口资源给用户提供固定不变的数据速率.文中通过分析移动网络中不同MBMS业务之间和非MBMS业务之间的资源抢占情况,发现动态调整MBMS业务数据速率可以极大提高网络利用率.根据此结论,设计可分层信息编码和设计不同数据流都可以实现动态控制.这两种解决方案都具有极高的使用价值.     

基于集成深度神经网络流量预测的动态网络切片迁移算法

针对5G网络切片(NS)场景下由于缺乏提前对物理网络资源进行感知而导致切片迁移滞后的问题,该文提出一种基于集成深度神经网络流量预测的动态切片调整和迁移算法(DSAM)。首先建立了基于计算、内存、带宽资源配置的网络总惩罚模型;其次,提出基于集成深度神经网络的流量预测算法预测未来网络流量情况,并根据流量类型的不同将其转换成对未来时刻物理网络的资源占用及切片的资源需求感知;最后,根据感知结果,以尽可能大地降低运营商惩罚为目标,通过动态切片调整和迁移策略将虚拟网络功能(VNF)和虚拟链路迁移到满足资源限制的物理节点和链路上。仿真结果表明,所提算法有效提高了切片迁移的效率和网络资源利用率。     

面向可靠性的5G网络切片重构及映射算法

针对传统网络切片映射方法资源利用率低且可靠性差的问题,该文提出了可靠性感知的网络切片(NS)重构及映射策略(RNSRE)。首先,建立了面向可靠性和资源的网络切片可靠映射效用函数。其次,综合考虑虚拟网络功能(VNF)的资源需求和位置约束,提出了一种VNF可靠性需求的度量方法。在此基础上,以最大化VNF可靠部署收益的同时最小化链路带宽资源开销为目标,建立了切片可靠映射整数线性规划模型。最后,针对不同的网络切片类型,提出了基于邻域搜索的网络切片映射算法和关键VNF备份的网络切片重构映射算法。仿真结果表明,所提算法在满足VNF可靠性需求的同时,提高了资源利用率,降低了映射的开销。     

一种新的对称CDMA系统中非对称业务下的呼叫允许控制策略

未来无线多媒体网络将以分组技术为基础,支持多种业务的传输,业务的QoS保证将受到一定的挑战.各运营商也将针对自己所服务的对象特点,定义各类业务的QoS等级,来提供具有不同QoS要求的业务.因此,呼叫允许控制(Call Admission Control,CAC)策略将要以分组业务为主要对象,即既要在充分利用系统资源的基础上保证各业务的QoS要求,又要适应各运营商之间的不同需求.因此本文提出一种新的对称CDMA系统中非对称业务下基于动态QoS保证的CAC策略.各运营商可根据自己的要求定义各业务的QoS等级.由于业务的不同特性,使得网络中上行链路和下行链路的业务呈现不对称性,为避免资源的浪费,将根据网络中的资源占有情况动态的地分配上行和下行链路中的资源.仿真结果表明,该策略可以自适应地保证各业务的QoS要求,提高了业务间的公平性和系统资源的利用率.     

An Elastic Sub-carrier and Power Allocation Algorithm Enabling Wireless Network Virtualization

Wireless mobile network virtualization enables physical mobile network operators (PMNO) to partition their network resources into smaller slices and assign each slice to an individual virtual mobile network operator and then manages these virtual networks in a more dynamic and cost-effective fashion. How a PMNO allocates resources to individual slices while ensuring resource elasticity is a key issue. This paper presents a resource allocation algorithm in such a network virtualization scenario where resource considered here includes both sub-carriers and transmission power. The overall algorithm involves the following two major processes: firstly to virtualize a physical wireless network into multiple slices each representing a virtual network, where resources are allocated elastically based on traffic loads and channel state information during virtualization; secondly, to carry out physical resource allocation within each virtual network (or slice). In particular the paper adopts orthogonal frequency division multiplexing as its physical layer to achieve more efficient resource utilization. A multi-step dynamic optimization approach is proposed to achieve sub-carrier allocation using binary integer programming and power allocation using nonlinear programming. The aim is to achieve the following design goals: virtual network isolation, and resource efficiency. The simulation results show that the above goals have been achieved.     

An efficient resource allocation to improve QoS of 5G slicing networks using general processor sharing‐based scheduling algorithm

Fifth generation (5G) slicing is an emerging technology for software‐defined networking/network function virtualization–enabled mobile networks. Improving the utilization and throughput to meet the quality of service (QoS) requirements of 5G slicing is very important for the operators of mobile networks. With growing data traffic from different applications of numerous smart mobile devices having several QoS requirements, we expect networks to face problems of congestion and overload that prevent the effective functioning of a radio access network (RAN). This paper proposes a more effective packet‐based scheduling scheme for data traffic by 5G slicing with two operation modes for improving the resource utilization of 5G cloud RAN and providing an efficient isolation of the 5G slices. These two operation modes are referred to as static sharing resource (SSR) scheme and dynamic sharing resources (DSR) scheme. The SSR scheme is a modified version of an existing method. The goal of this approach is to reallocate the shared available resources of 5G network fairly and maximize the utilization of bandwidth while protecting a 5G slice from overwhelming other 5G slices. Throughput and delays of the system model are also discussed to show its performance limits. On the basis of the simulation outcomes, we observed that the proposed DSR scheme outperforms the SSR scheme in terms of provided delay and throughput. In addition, the token bucket parameters together with the assigned capacity weight for each slice can be selected and configured based on the required QoS. Finally, a good estimate for the maximum delay bounds of the slices is provided by the derived theoretical delay bound.     

Incentive Scheme for Slice Cooperation Based on D2D Communication in 5G Networks

In the 5th generation(5G)wireless communication networks,network slicing emerges where network operators(NPs)form isolated logical slices by the same cellular network infrastructure and spectrum resource.In coverage regions of access points(APs)shared by slices,device to device(D2D)communication can occur among different slices,i.e.,one device acts as D2D relay for another device serving by a different slice,which is defined as slice cooperation in this paper.Since selfish slices will not help other slices by cooperation voluntarily and unconditionally,this paper designs a novel resource allocation scheme to stimulate slice cooperation.The main idea is to encourage slice to perform cooperation for other slices by rewarding it with higher throughput.The proposed incentive scheme for slice cooperation is formulated by an optimal problem,where cooperative activities are introduced to the objective function.Since optimal solutions of the formulated problem are long term statistics,though can be obtained,a practical online slice scheduling algorithm is designed,which can obtain optimal solutions of the formulated maximal problem.Lastly,the throughput isolation indexes are defined to evaluate isolation performance of slice.According to simulation results,the proposed incentive scheme for slice cooperation can stimulate slice cooperation effectively,and the isolation of slice is also simulated and discussed.     

面向服务的车辆网络切片协调智能体设计

针对现有研究中缺乏对车辆网络切片的部署和管理，该文设计了车辆网络切片架构中的切片协调智能体。首先基于K-means++聚类算法将车联网通信业务根据相似度进行聚类并映射到对应的切片中。其次，在考虑应用场景间的时空差异导致的无线资源利用不均衡现象，提出了共享比例公平方案以实现对无线资源的高效及差异化利用。最后，为了保证切片服务需求，采用线性规划障碍方法求解最优的切片权重分配，使切片负载变化容忍度最大化。仿真结果表明，共享比例公平方案相比于静态切片方案平均比特传输时延(BTD)更小，在每切片用户数为30的情况下均匀分布用户负载场景中二者的BTD增益为1.4038，且在不同的用户负载分布场景下都能求出最优的切片权重分配。     

An elastic resource allocation algorithm enabling wireless network virtualization

Following the wired network virtualization, virtualization of wireless networks becomes the next step aiming to provide network or infrastructure providers with the ability to manage and control their networks in a more dynamic fashion. The benefit of the wireless mobile network virtualization is a more agile business model where virtual mobile network operators (MNOs) can request and thus pay physical MNOs in a more pay‐as‐you‐use manner. This paper presents some resource allocation algorithms for joint network virtualization and resource allocation of wireless networks. The overall algorithm involves the following two major processes: firstly, to virtualize a physical wireless network into multiple slices, each representing a virtual network, and secondly, to carry out physical resource allocation within each virtual network (or slice). In particular, the paper adopts orthogonal frequency division multiplexing (OFDM) as its physical layer to achieve more efficient resource utilization. Therefore, the resource allocation is conducted in terms of sub‐carriers. Although the motivation and algorithm design are based on IEEE 802.16 or WiMAX networks, the principle and algorithmic essence are also applicable to other OFDM access‐based wireless networks. The aim was to achieve the following design goals: virtual network isolation and resource efficiency. The latter is measured in terms of network throughput and packet delivery ratio. The simulation results show that the aforementioned goals have been achieved. Copyright © 2012 John Wiley & Sons, Ltd.     

Quality of Service Modelling of Virtualized Wireless Networks: A Network Calculus Approach

Wireless network virtualization is an emerging technology that logically divides a wireless network element, such as a base station (BS), into multiple slices with each slice serving as a standalone virtual BS. In such a way, one physical mobile wireless network can be partitioned into multiple virtual networks each operating as an independent wireless network. Wireless virtual networks, as composed of these virtual BSs, need to provide quality of service (QoS) to mobile end user services. Key QoS parameters include buffer queue length, network delay and effective bandwidth, in particular their upper bound forms. This paper presents a QoS model for such a wireless virtual network addressing these parameters. This QoS model considers resources of both physical nodes and virtual nodes and provides a realistic modelling of the delay and bandwidth behaviours of wireless virtual networks. Network calculus (NC), which usually provides finer insight into a system, is utilized to fulfil the modelling task. The numerical results have shown the effectiveness of the proposed model. The model is useful for both off-line network planning and online network admission control.     

Wireless resource virtualization: opportunities,challenges, and solutions

Wireless resource virtualization (WRV) is currently emerging as a key technology to overcome the major challenges facing the mobile network operators (MNOs) such as reducing the capital, minimizing the operating expenses, improving the quality of service, and satisfying the growing demand for mobile services. Achieving such conflicting objectives simultaneously requires a highly efficient utilization of the available resources including the network infrastructure and the reserved spectrum. In this paper, the most dominant WRV frameworks are discussed where different levels of network infrastructure and spectrum resources are shared between multiple MNOs. Moreover, we summarize the major benefits and most pressing business challenges of deploying WRV. We further highlight the technical challenges and requirements for abstraction and sharing of spectrum resources in next generation networks. In addition, we provide guidelines for implementing comprehensive solutions that are able to abstract and share the spectrum resources in next generation network. The paper also presents an efficient algorithm for base station virtualization in long‐term evolution (LTE) networks to share the wireless resources between MNOs who apply different scheduling polices. The proposed algorithm maintains a high‐level of isolation and offers throughput performance gain. Copyright © 2016 John Wiley & Sons, Ltd.