An important requirement in a military domain is a highly reliable mobility management method,especially when components of the networks aremoving in tactical network environments.To increase reliability,themobility m...An important requirement in a military domain is a highly reliable mobility management method,especially when components of the networks aremoving in tactical network environments.To increase reliability,themobility management technology of the tactical network should be able to reflect the characteristics of the tactical network,such as a limited environment,failure,and hierarchical unit structure.In this paper,we propose a proxy-based hierarchical distributedmobilitymanagement scheme,which is highly focused on tactical networks.Considering the characteristics of tactical networks,the proposed scheme is composed of the following:1)a proxy-based method,2)a distributed mobility management method that synchronizes a mobility database between entities,and 3)a method of managing mobility by dividing the tactical network into upper and lower layers.Mathematical analysis and modeling and simulation results demonstrate that the method outperforms the existing state-of-the-art method in overcoming entity failure,handover cost,and delay in tactical environments.展开更多
The installation of small cells in a 5G network extends the maximum coverage and provides high availability.However,this approach increases the handover overhead in the Core Network(CN)due to frequent handoffs.The var...The installation of small cells in a 5G network extends the maximum coverage and provides high availability.However,this approach increases the handover overhead in the Core Network(CN)due to frequent handoffs.The variation of user density and movement inside a region of small cells also increases the handover overhead in CN.However,the present 5G system cannot reduce the handover overhead in CN under such circumstances because it relies on a traditionally rigid and complex hierarchical sequence for a handover procedure.Recently,Not Only Stack(NO Stack)architecture has been introduced for Radio Access Network(RAN)to reduce the signaling during handover.This paper proposes a system based on NO Stack architecture and solves the aforementioned problem by adding a dedicated local mobility controller to the edge cloud for each cluster.The dedicated cluster controller manages the user mobility locally inside a cluster and also maintains the forwarding data of a mobile user locally.To reduce the latency for X2-based handover requests,an edge cloud infrastructure has been also developed to provide high-computing for dedicated controllers at the edge of a cellular network.The proposed system is also compared with the traditional 3GPP architecture and other works in the context of overhead and delay caused by X2-based handover requests during user mobility.Simulated results show that the inclusion of a dedicated local controller for small clusters together with the implementation of NO Stack framework reduces the significant amount of overhead of X2-based handover requests at CN.展开更多
Dual connectivity(DC)is regarded as a promising technology to increase users’throughput,provide radio link robustness,and improve load-balancing among base stations(BSs).However,since the introduction of DC makes the...Dual connectivity(DC)is regarded as a promising technology to increase users’throughput,provide radio link robustness,and improve load-balancing among base stations(BSs).However,since the introduction of DC makes the mobility of network more complex and diversified,especially the mobility management of heterogeneous networks(HetNets)based on DC faces great challenges.Taking event-A3-based measurement report as the trigger condition for handover(HO),this paper compares and evaluates the influences of HO of master nodes(MNs)and secondary nodes(SNs)on link reliability in different bearing modes.Particularly,hybrid automatic repeat request(HARQ),throughput,channel quality indicators(CQIs),and data packets queuing time are taken as link reliability analysis indicators.Besides,we study how DC utilizes the traffic split ratio between MNs and SNs to maximize the superiority of throughput.Simulation results show that DC can effectively reduce the impact of HO on the number of HARQ and increase the throughput of users.When the data traffic is tilted to the secondary nodes,the superiority of throughput is more obvious.展开更多
Current mobility management schemes usually represent centralized or hierarchical architectures,which force data traffic to be processed by a centralized mobility anchor.This allows the mobile node(MN)to be reachable ...Current mobility management schemes usually represent centralized or hierarchical architectures,which force data traffic to be processed by a centralized mobility anchor.This allows the mobile node(MN)to be reachable anywhere and provides an efficient method for seamless session continuity.However,all of the signal messages and data traffic converge on particular mobility anchor,which causes excessive signaling and traffic at the centralized mobility anchor and single point of failure issues as data traffic increases.To overcome these limitations and handle increasing data traffic,the distributed mobility management(DMM)scheme has emerged as an alternative solution.Although previous researches have been conducted on DMM support,because their schemes employ an unconditional way to make direct paths after handover,they have some drawbacks,such as several signaling and chain of tunneling problems.Therefore,this paper introduces a new DMM scheme which adaptively creates a direct path.To support it,we present the path selection algorithm,which selects the most efficient path between a direct path and no direct path based on routing hops and traffic load.Through the performance analysis and results,we confirm that the proposed scheme is superior in terms of signaling and packet delivery costs.展开更多
The fifth generation(5G) network is expected to support significantly large amount of mobile data traffic and huge number of wireless connections,to achieve better spectrum- and energy-efficiency,as well as quality of...The fifth generation(5G) network is expected to support significantly large amount of mobile data traffic and huge number of wireless connections,to achieve better spectrum- and energy-efficiency,as well as quality of service(QoS) in terms of delay,reliability and security.Furthermore,the 5G network shall also incorporate high mobility requirements as an integral part,providing satisfactory service to users travelling at a speed up to 500 km/h.This paper provides a survey of potential high mobility wireless communication(HMWC) techniques for 5G network.After discussing the typical requirements and challenges of HMWC,key techniques to cope with the challenges are reviewed,including transmission techniques under the fast timevarying channels,network architecture with mobility support,and mobility management.Finally,future research directions on 5G high mobility communications are given.展开更多
Fifth-generation(5G)cellular networks offer high transmission rates in dense urban environments.However,a massive deployment of small cells will be required to provide wide-area coverage,which leads to an increase in ...Fifth-generation(5G)cellular networks offer high transmission rates in dense urban environments.However,a massive deployment of small cells will be required to provide wide-area coverage,which leads to an increase in the number of handovers(HOs).Mobility management is an important issue that requires considerable attention in heterogeneous networks,where 5G ultra-dense small cells coexist with current fourth-generation(4G)networks.Although mobility robustness optimization(MRO)and load balancing optimization(LBO)functions have been introduced in the 3GPP standard to address HO problems,non-robust and nonoptimal algorithms for selecting appropriate HO control parameters(HCPs)still exist,and an optimal solution is subjected to compromise between LBO and MRO functions.Thus,HO decision algorithms become inefficient.This paper proposes a conflict resolution technique to address the contradiction between MRO and LBO functions.The proposed technique exploits received signal reference power(RSRP),cell load and user speed to adapt HO margin(HM)and time to trigger(TTT).Estimated HM and TTT depend on a weighting function and HO type which is represented by user status during mobility.The proposed technique is validated with other existing algorithms from the literature.Simulation results demonstrate that the proposed technique outperforms existing algorithms overall performance metrics.The proposed technique reduces the overall average HO ping-pong probability,HO failure rate and interruption time by more than 90%,46%and 58%,respectively,compared with the other schemes overall speed scenarios and simulation time.展开更多
IPv6 over Low Power Wireless Personal Area Network(6LoWPAN)connects the highly constrained sensor nodes with the internet using the IPv6 protocol.6LoWPAN has improved the scalability of the Internet of Things(IoTs)inf...IPv6 over Low Power Wireless Personal Area Network(6LoWPAN)connects the highly constrained sensor nodes with the internet using the IPv6 protocol.6LoWPAN has improved the scalability of the Internet of Things(IoTs)infrastructure and allows mobile nodes to send packets over the IEEE 802.15.4 wireless network.Several mobility managements schemes have been suggested for handling the registration and handover procedures in 6LoWPAN.However,these schemes have performance constraints,such as increased transmission cost,signalling overhead,registration,and handover latency.To address these issues,we propose a novel cluster-based group mobility scheme(CGM6)for 6LoWPAN.To reduce the signalling cost in the CGM6 scheme,we propose to combine the functions of the Authentication,Authorization and Accounting(AAA)server and Local Mobility Anchor(LMA)in AMAG6(AAA+MAG for 6LoWPAN).AMAG6 acts as a cluster head and exchange its information directly with its neighbouring AMAG6 during the mobility.Furthermore,AMAG6 is responsible for the binding and authentication process.To reduce the transmission cost,we also propose enhancements in registration and Handover procedures.The performance of CGM6 is evaluated through extensive simulations.The simulation results show that CGM6 has reduced the handoff latency by 32%,registration delay by 11%and transmission cost by 37%compared to the state-of-the-art mobility management schemes.展开更多
Drone applications in 5th generation(5G)networks mainly focus on services and use cases such as providing connectivity during crowded events,human-instigated disasters,unmanned aerial vehicle traffic management,intern...Drone applications in 5th generation(5G)networks mainly focus on services and use cases such as providing connectivity during crowded events,human-instigated disasters,unmanned aerial vehicle traffic management,internet of things in the sky,and situation awareness.4G and 5G cellular networks face various challenges to ensure dynamic control and safe mobility of the drone when it is tasked with delivering these services.The drone can fly in three-dimensional space.The drone connectivity can suffer from increased handover cost due to several reasons,including variations in the received signal strength indicator,co-channel interference offered to the drone by neighboring cells,and abrupt drop in lobe edge signals due to antenna nulls.The baseline greedy handover algorithm only ensures the strongest connection between the drone and small cells so that the drone may experience several handovers.Intended for fast environment learning,machine learning techniques such as Q-learning help the drone fly with minimum handover cost along with robust connectivity.In this study,we propose a Q-learning-based approach evaluated in three different scenarios.The handover decision is optimized gradually using Q-learning to provide efficient mobility support with high data rate in time-sensitive applications,tactile internet,and haptics communication.Simulation results demonstrate that the proposed algorithm can effectively minimize the handover cost in a learning environment.This work presents a notable contribution to determine the optimal route of drones for researchers who are exploring UAV use cases in cellular networks where a large testing site comprised of several cells with multiple UAVs is under consideration.展开更多
There has been an exponential rise in mobile data traffic in recent times due to the increasing popularity of portable devices like tablets,smartphones,and laptops.The rapid rise in the use of these portable devices h...There has been an exponential rise in mobile data traffic in recent times due to the increasing popularity of portable devices like tablets,smartphones,and laptops.The rapid rise in the use of these portable devices has put extreme stress on the network service providers while forcing telecommunication engineers to look for innovative solutions to meet the increased demand.One solution to the problem is the emergence of fifth-generation(5G)wireless communication,which can address the challenges by offering very broad wireless area capacity and potential cut-power consumption.The application of small cells is the fundamental mechanism for the 5Gtechnology.The use of small cells can enhance the facility for higher capacity and reuse.However,it must be noted that small cells deployment will lead to frequent handovers of mobile nodes.Considering the importance of small cells in 5G,this paper aims to examine a new resource management scheme that can work to minimize the rate of handovers formobile phones through careful resources allocation in a two-tier network.Therefore,the resource management problem has been formulated as an optimization issue thatwe aim to overcome through an optimal solution.To find a solution to the existing problem of frequent handovers,a heuristic approach has been used.This solution is then evaluated and validated through simulation and testing,during which the performance was noted to improve by 12%in the context of handover costs.Therefore,this model has been observed to be more efficient as compared to the existing model.展开更多
In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the grow...In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the growing challenges induced by time-varying topology,intermittent inter-satellite link and dramatically increased satellite constellation size.This survey covers the latest progress of software defined satellite networks,including key techniques,existing solutions,challenges,opportunities,and simulation tools.To the best of our knowledge,this paper is the most comprehensive survey that covers the latest progress of software defined satellite networks.An open GitHub repository is further created where the latest papers on this topic will be tracked and updated periodically.Compared with these existing surveys,this survey contributes from three aspects:(1)an up-to-date SDN-oriented review for the latest progress of key techniques and solutions in software defined satellite networks;(2)an inspiring summary of existing challenges,new research opportunities and publicly available simulation tools for follow-up studies;(3)an effort of building a public repository to track new results.展开更多
Under various deployment circumstances,fifth-generation(5G)telecommunications delivers improved network compound management with fast communication channels.Due to the introduction of the Internet of Things(IoT)in dat...Under various deployment circumstances,fifth-generation(5G)telecommunications delivers improved network compound management with fast communication channels.Due to the introduction of the Internet of Things(IoT)in data management,the majority of the ultra-dense network models in 5G networks frequently have decreased spectral efficiency,weak handover management,and vulnerabilities.The majority of traditional handover authentication models are seriously threatened,making them vulnerable to a variety of security attacks.The authentication of networked devices is the most important issue.Therefore,a model that incorporates the handover mechanism and authentication model must be created.This article uses a fuzzy logic model to create a handover and key management system that focuses on cloud handover management and authentication performance.In order to decrease delays in 5G networks,the fuzzy logic is built with multiple criteria that aim to reduce the number of executed handovers and target cell selection.The simulation is run to evaluate the model’s performance in terms of latency,spatial complexity,and other metrics related to authentication attack validation.展开更多
In next generation networks,mobility management will be a critical issue due to dense base station(BS)deployment,for which user and control plane split architecture provides a promising solution.Jointly designing such...In next generation networks,mobility management will be a critical issue due to dense base station(BS)deployment,for which user and control plane split architecture provides a promising solution.Jointly designing such architecture with nonorthogonal transmission brings in more flexibility to further improve system efficiency.This paper proposes a non-orthogonal transmission design for user and control plane split architecture.In this design,user equipments(UEs)will select the BS providing the strongest received signal to associate its data channel,but constantly connect its control channel to the nearest macro-cell BS(MBS).Upon non-orthogonal transmission,an MBS can multiplex data traffics and control signals on the same resource.Stochastic geometry based analysis is carried out to investigate outage probability,which extends its regular definition by jointly considering data and control channels,and then mobility-aware outage rate.Numerical results show that:1)The proposed split architecture alleviates the increase in handover rate for ultra dense networking,compared with conventional architecture.2)Non-orthogonal transmission outperforms traditional orthogonal transmission in the split architecture,because it is capable of accommodating more control channels.3)By carefully adjusting power levels,minimum outage probabilities can be reached for macrocell UEs in the proposed design.展开更多
Despite the seemingly exponential growth of mobile and wireless communication,this same technology aims to offer uninterrupted access to different wireless systems like Radio Communication,Bluetooth,and Wi-Fi to achie...Despite the seemingly exponential growth of mobile and wireless communication,this same technology aims to offer uninterrupted access to different wireless systems like Radio Communication,Bluetooth,and Wi-Fi to achieve better network connection which in turn gives the best quality of service(QoS).Many analysts have established many handover decision systems(HDS)to enable assured continuous mobility between various radio access technologies.Unbrokenmobility is one of themost significant problems considered in wireless communication networks.Each application needs a distinct QoS,so the network choice may shift appropriately.To achieve this objective and to choose the finest networks,it is important to select a best decision making algorithm that chooses the most effective network for every application that the user requires,dependent on QoS measures.Therefore,the main goal of the proposed system is to provide an enhanced vertical handover(VHO)decision making programby using aMulti-CriteriaFuzzy-Based algorithm to choose the best network.Enhanced Multi-Criteria algorithms and a Fuzzy-Based algorithm is implemented successfully for optimal network selection and also to minimize the probability of false handover.Furthermore,a double packet buffer is utilized to decrease the packet loss by 1.5%and to reduce the number of handovers up to 50%compared to the existing systems.In addition,the network setup has an optimized mobilitymanagement system to supervise the movement of the mobile nodes.展开更多
This study explores whether manager mobility can influence syndications between private equity(PE)firms by constructing coupling network models.Using data from China’s private equity market from 1993 to 2017,we found...This study explores whether manager mobility can influence syndications between private equity(PE)firms by constructing coupling network models.Using data from China’s private equity market from 1993 to 2017,we found that driving forces,resistant forces,and network structure play significant roles in determining resource flows between PE firms.Specifically,driving forces indicate that managers moving from domestic and foreign PE firms to state-owned PE firms are more likely to induce syndications.Furthermore,if the manager is promoted when changing jobs,mobility is likely to enhance the flow of resources.Resistant forces indicate that increased geographical distance reduces syndications.As for the influence of structure,if managers leave PE firms with higher status,they are more likely to induce syndications.This study contributes to the coupling network literature by providing a clarified three-factor framework.By exploring the characteristic of managers in state-owned private equity firms,we specified the syndication theory in China.This study can help private equity firms hire valuable managers and expand syndication networks in practice.展开更多
The future generation networks or 4G networks constitute of varied technologies converged over the Internet protocol version 6(IPv6) core. The 4G networks offer varied services over different interfaces to the user no...The future generation networks or 4G networks constitute of varied technologies converged over the Internet protocol version 6(IPv6) core. The 4G networks offer varied services over different interfaces to the user nodes. Mobility management in 4G networks is an issue that exists. The handover protocols for mobility management in 4G networks that currently exist, do not consider wireless signal degradation during handover operations. This paper introduces the Noise Resilient Reduced Registration Time Care of Mobile IP(NR RRTC:MIP) protocol for handover management. A handover decision algorithm based on the signal strength measured by the user nodes is considered in the NR RRTC: MIP protocol. A simulation study is discussed in the paper to evaluate the performance of the NR RRTC: MIP protocol. The results obtained from the simulation study prove that the NR RRTC: MIP protocol effectively reduces handover latencies and improves network performance.展开更多
Proxy mobile Internet protocol version 6(PMIPv6)is a network-based mobility management protocol proposed by Internet Engineering Task Force(IETF),which allows nodes to remain service connectivity while moving around i...Proxy mobile Internet protocol version 6(PMIPv6)is a network-based mobility management protocol proposed by Internet Engineering Task Force(IETF),which allows nodes to remain service connectivity while moving around in the IPv6 Internet.PMIPv6 is different from the host-based mobility management protocols(mobile Internet protocol version(MIPv6),hierarchical mobile IPv6(HMIPv6),fast handover for mobile IPv6(FMIPv6),and fast handover in hierarchical mobile IPv6(F-HMIPv6)),whose signaling are transferred among some network entities except mobile node(MN).This paper focuses on the analytical modeling of performance analysis for PMIPv6 and other protocols using IEEE802.16-based wireless metropolitan area networks as the wireless access network.The performances of these protocols are evaluated by some metrics like handover latency,service disruption time,and binding update cost.Numerical results show that PMIPv6 has better performance.展开更多
Indoor wireless communication networking has received significant attention along with the growth of indoor data traffic.VLC(Visible Light Communication)as a novel wireless communication technology with the advantages...Indoor wireless communication networking has received significant attention along with the growth of indoor data traffic.VLC(Visible Light Communication)as a novel wireless communication technology with the advantages of a high data rate,license-free spectrum and safety provides a practical solution for the indoor high-speed transmission of large data traffic.However,limited coverage is an inherent feature of VLC.In this paper,we propose a novel hybrid VLC-Wi-Fi system that integrates multiple links to achieve an indoor high-speed wide-coverage network combined with multiple access,a multi-path transmission control protocol,mobility management and cell handover.Furthermore,we develop a hybrid network experiment platform,the experimental results of which show that the hybrid VLC-Wi-Fi network outperforms both single VLC and Wi-Fi networks with better coverage and greater network capacity.展开更多
基金This work was supported by the Agency for Defense Development.
文摘An important requirement in a military domain is a highly reliable mobility management method,especially when components of the networks aremoving in tactical network environments.To increase reliability,themobility management technology of the tactical network should be able to reflect the characteristics of the tactical network,such as a limited environment,failure,and hierarchical unit structure.In this paper,we propose a proxy-based hierarchical distributedmobilitymanagement scheme,which is highly focused on tactical networks.Considering the characteristics of tactical networks,the proposed scheme is composed of the following:1)a proxy-based method,2)a distributed mobility management method that synchronizes a mobility database between entities,and 3)a method of managing mobility by dividing the tactical network into upper and lower layers.Mathematical analysis and modeling and simulation results demonstrate that the method outperforms the existing state-of-the-art method in overcoming entity failure,handover cost,and delay in tactical environments.
基金This research was supported by the MSIT(Ministry of Science and ICT),Korea,under the ITRC(Information Technology Research Center)support program(1ITP-2021-2017-0-01633)supervised by the IITP(Institute for Information&communications Technology Planning&Evaluation)This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2016R1D1A1B01016322).
文摘The installation of small cells in a 5G network extends the maximum coverage and provides high availability.However,this approach increases the handover overhead in the Core Network(CN)due to frequent handoffs.The variation of user density and movement inside a region of small cells also increases the handover overhead in CN.However,the present 5G system cannot reduce the handover overhead in CN under such circumstances because it relies on a traditionally rigid and complex hierarchical sequence for a handover procedure.Recently,Not Only Stack(NO Stack)architecture has been introduced for Radio Access Network(RAN)to reduce the signaling during handover.This paper proposes a system based on NO Stack architecture and solves the aforementioned problem by adding a dedicated local mobility controller to the edge cloud for each cluster.The dedicated cluster controller manages the user mobility locally inside a cluster and also maintains the forwarding data of a mobile user locally.To reduce the latency for X2-based handover requests,an edge cloud infrastructure has been also developed to provide high-computing for dedicated controllers at the edge of a cellular network.The proposed system is also compared with the traditional 3GPP architecture and other works in the context of overhead and delay caused by X2-based handover requests during user mobility.Simulated results show that the inclusion of a dedicated local controller for small clusters together with the implementation of NO Stack framework reduces the significant amount of overhead of X2-based handover requests at CN.
基金supported by the National Natural Science Foundation of China(Nos.62161035 and 61861034)Inner Mongolia Natural Science Foundation(No.2022MS06022)。
文摘Dual connectivity(DC)is regarded as a promising technology to increase users’throughput,provide radio link robustness,and improve load-balancing among base stations(BSs).However,since the introduction of DC makes the mobility of network more complex and diversified,especially the mobility management of heterogeneous networks(HetNets)based on DC faces great challenges.Taking event-A3-based measurement report as the trigger condition for handover(HO),this paper compares and evaluates the influences of HO of master nodes(MNs)and secondary nodes(SNs)on link reliability in different bearing modes.Particularly,hybrid automatic repeat request(HARQ),throughput,channel quality indicators(CQIs),and data packets queuing time are taken as link reliability analysis indicators.Besides,we study how DC utilizes the traffic split ratio between MNs and SNs to maximize the superiority of throughput.Simulation results show that DC can effectively reduce the impact of HO on the number of HARQ and increase the throughput of users.When the data traffic is tilted to the secondary nodes,the superiority of throughput is more obvious.
基金MKE(the Ministry of Knowledge Economy),Korea,under the Convergence-ITRC support program(NIPA-2011C6150-1101-0004)supervised by the NIPA(National IT Industry Promotion Agency)KCC(Korea Communications Commis-sion),Korea,under the R&D program supervised by the KCA(Korea Communications Agency)(KCA-2011-08913-05001)
文摘Current mobility management schemes usually represent centralized or hierarchical architectures,which force data traffic to be processed by a centralized mobility anchor.This allows the mobile node(MN)to be reachable anywhere and provides an efficient method for seamless session continuity.However,all of the signal messages and data traffic converge on particular mobility anchor,which causes excessive signaling and traffic at the centralized mobility anchor and single point of failure issues as data traffic increases.To overcome these limitations and handle increasing data traffic,the distributed mobility management(DMM)scheme has emerged as an alternative solution.Although previous researches have been conducted on DMM support,because their schemes employ an unconditional way to make direct paths after handover,they have some drawbacks,such as several signaling and chain of tunneling problems.Therefore,this paper introduces a new DMM scheme which adaptively creates a direct path.To support it,we present the path selection algorithm,which selects the most efficient path between a direct path and no direct path based on routing hops and traffic load.Through the performance analysis and results,we confirm that the proposed scheme is superior in terms of signaling and packet delivery costs.
基金supported by the National Basic Research Program of China (973 Program No.2012CB316100)
文摘The fifth generation(5G) network is expected to support significantly large amount of mobile data traffic and huge number of wireless connections,to achieve better spectrum- and energy-efficiency,as well as quality of service(QoS) in terms of delay,reliability and security.Furthermore,the 5G network shall also incorporate high mobility requirements as an integral part,providing satisfactory service to users travelling at a speed up to 500 km/h.This paper provides a survey of potential high mobility wireless communication(HMWC) techniques for 5G network.After discussing the typical requirements and challenges of HMWC,key techniques to cope with the challenges are reviewed,including transmission techniques under the fast timevarying channels,network architecture with mobility support,and mobility management.Finally,future research directions on 5G high mobility communications are given.
基金The research leading to these results has received funding from The Research Council(TRC)of the Sultanate of Oman under the Block Funding Program with agreement no.TRC/BFP/ASU/01/2019,and it was also supported in part by the Universiti Sains Islam Malaysia(USIM),Malaysia.
文摘Fifth-generation(5G)cellular networks offer high transmission rates in dense urban environments.However,a massive deployment of small cells will be required to provide wide-area coverage,which leads to an increase in the number of handovers(HOs).Mobility management is an important issue that requires considerable attention in heterogeneous networks,where 5G ultra-dense small cells coexist with current fourth-generation(4G)networks.Although mobility robustness optimization(MRO)and load balancing optimization(LBO)functions have been introduced in the 3GPP standard to address HO problems,non-robust and nonoptimal algorithms for selecting appropriate HO control parameters(HCPs)still exist,and an optimal solution is subjected to compromise between LBO and MRO functions.Thus,HO decision algorithms become inefficient.This paper proposes a conflict resolution technique to address the contradiction between MRO and LBO functions.The proposed technique exploits received signal reference power(RSRP),cell load and user speed to adapt HO margin(HM)and time to trigger(TTT).Estimated HM and TTT depend on a weighting function and HO type which is represented by user status during mobility.The proposed technique is validated with other existing algorithms from the literature.Simulation results demonstrate that the proposed technique outperforms existing algorithms overall performance metrics.The proposed technique reduces the overall average HO ping-pong probability,HO failure rate and interruption time by more than 90%,46%and 58%,respectively,compared with the other schemes overall speed scenarios and simulation time.
文摘IPv6 over Low Power Wireless Personal Area Network(6LoWPAN)connects the highly constrained sensor nodes with the internet using the IPv6 protocol.6LoWPAN has improved the scalability of the Internet of Things(IoTs)infrastructure and allows mobile nodes to send packets over the IEEE 802.15.4 wireless network.Several mobility managements schemes have been suggested for handling the registration and handover procedures in 6LoWPAN.However,these schemes have performance constraints,such as increased transmission cost,signalling overhead,registration,and handover latency.To address these issues,we propose a novel cluster-based group mobility scheme(CGM6)for 6LoWPAN.To reduce the signalling cost in the CGM6 scheme,we propose to combine the functions of the Authentication,Authorization and Accounting(AAA)server and Local Mobility Anchor(LMA)in AMAG6(AAA+MAG for 6LoWPAN).AMAG6 acts as a cluster head and exchange its information directly with its neighbouring AMAG6 during the mobility.Furthermore,AMAG6 is responsible for the binding and authentication process.To reduce the transmission cost,we also propose enhancements in registration and Handover procedures.The performance of CGM6 is evaluated through extensive simulations.The simulation results show that CGM6 has reduced the handoff latency by 32%,registration delay by 11%and transmission cost by 37%compared to the state-of-the-art mobility management schemes.
基金This work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2018R1D1A1B07049877)and the Strengthening R&D Capability Program of Sejong University.
文摘Drone applications in 5th generation(5G)networks mainly focus on services and use cases such as providing connectivity during crowded events,human-instigated disasters,unmanned aerial vehicle traffic management,internet of things in the sky,and situation awareness.4G and 5G cellular networks face various challenges to ensure dynamic control and safe mobility of the drone when it is tasked with delivering these services.The drone can fly in three-dimensional space.The drone connectivity can suffer from increased handover cost due to several reasons,including variations in the received signal strength indicator,co-channel interference offered to the drone by neighboring cells,and abrupt drop in lobe edge signals due to antenna nulls.The baseline greedy handover algorithm only ensures the strongest connection between the drone and small cells so that the drone may experience several handovers.Intended for fast environment learning,machine learning techniques such as Q-learning help the drone fly with minimum handover cost along with robust connectivity.In this study,we propose a Q-learning-based approach evaluated in three different scenarios.The handover decision is optimized gradually using Q-learning to provide efficient mobility support with high data rate in time-sensitive applications,tactile internet,and haptics communication.Simulation results demonstrate that the proposed algorithm can effectively minimize the handover cost in a learning environment.This work presents a notable contribution to determine the optimal route of drones for researchers who are exploring UAV use cases in cellular networks where a large testing site comprised of several cells with multiple UAVs is under consideration.
基金This work was supported by the Taif University Researchers Supporting Project number(TURSP-2020/79),Taif University,Taif,Saudi Arabia.
文摘There has been an exponential rise in mobile data traffic in recent times due to the increasing popularity of portable devices like tablets,smartphones,and laptops.The rapid rise in the use of these portable devices has put extreme stress on the network service providers while forcing telecommunication engineers to look for innovative solutions to meet the increased demand.One solution to the problem is the emergence of fifth-generation(5G)wireless communication,which can address the challenges by offering very broad wireless area capacity and potential cut-power consumption.The application of small cells is the fundamental mechanism for the 5Gtechnology.The use of small cells can enhance the facility for higher capacity and reuse.However,it must be noted that small cells deployment will lead to frequent handovers of mobile nodes.Considering the importance of small cells in 5G,this paper aims to examine a new resource management scheme that can work to minimize the rate of handovers formobile phones through careful resources allocation in a two-tier network.Therefore,the resource management problem has been formulated as an optimization issue thatwe aim to overcome through an optimal solution.To find a solution to the existing problem of frequent handovers,a heuristic approach has been used.This solution is then evaluated and validated through simulation and testing,during which the performance was noted to improve by 12%in the context of handover costs.Therefore,this model has been observed to be more efficient as compared to the existing model.
基金This work is supported by the Fundamental Research Funds for the Central Universities.
文摘In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the growing challenges induced by time-varying topology,intermittent inter-satellite link and dramatically increased satellite constellation size.This survey covers the latest progress of software defined satellite networks,including key techniques,existing solutions,challenges,opportunities,and simulation tools.To the best of our knowledge,this paper is the most comprehensive survey that covers the latest progress of software defined satellite networks.An open GitHub repository is further created where the latest papers on this topic will be tracked and updated periodically.Compared with these existing surveys,this survey contributes from three aspects:(1)an up-to-date SDN-oriented review for the latest progress of key techniques and solutions in software defined satellite networks;(2)an inspiring summary of existing challenges,new research opportunities and publicly available simulation tools for follow-up studies;(3)an effort of building a public repository to track new results.
文摘Under various deployment circumstances,fifth-generation(5G)telecommunications delivers improved network compound management with fast communication channels.Due to the introduction of the Internet of Things(IoT)in data management,the majority of the ultra-dense network models in 5G networks frequently have decreased spectral efficiency,weak handover management,and vulnerabilities.The majority of traditional handover authentication models are seriously threatened,making them vulnerable to a variety of security attacks.The authentication of networked devices is the most important issue.Therefore,a model that incorporates the handover mechanism and authentication model must be created.This article uses a fuzzy logic model to create a handover and key management system that focuses on cloud handover management and authentication performance.In order to decrease delays in 5G networks,the fuzzy logic is built with multiple criteria that aim to reduce the number of executed handovers and target cell selection.The simulation is run to evaluate the model’s performance in terms of latency,spatial complexity,and other metrics related to authentication attack validation.
基金supported by the Youth Innovation Foundation of Xiamen(3502Z20206067)the Natural Science Foundation of Fujian Province,China(2021J011219,2022J011276)+3 种基金the National Natural Science Foundation of China(61801412,62201482)the National Key Research and Development Program of China(2021YFB2900801)Beijing Natural Science Foundation(L212004)China University Industry-University-Research Collaborative Innovation Fund(2021FNA05001).
文摘In next generation networks,mobility management will be a critical issue due to dense base station(BS)deployment,for which user and control plane split architecture provides a promising solution.Jointly designing such architecture with nonorthogonal transmission brings in more flexibility to further improve system efficiency.This paper proposes a non-orthogonal transmission design for user and control plane split architecture.In this design,user equipments(UEs)will select the BS providing the strongest received signal to associate its data channel,but constantly connect its control channel to the nearest macro-cell BS(MBS).Upon non-orthogonal transmission,an MBS can multiplex data traffics and control signals on the same resource.Stochastic geometry based analysis is carried out to investigate outage probability,which extends its regular definition by jointly considering data and control channels,and then mobility-aware outage rate.Numerical results show that:1)The proposed split architecture alleviates the increase in handover rate for ultra dense networking,compared with conventional architecture.2)Non-orthogonal transmission outperforms traditional orthogonal transmission in the split architecture,because it is capable of accommodating more control channels.3)By carefully adjusting power levels,minimum outage probabilities can be reached for macrocell UEs in the proposed design.
基金Taif University Researchers Supporting Project Number(TURSP-2020/36),Taif University,Taif,Saudi Arabia.
文摘Despite the seemingly exponential growth of mobile and wireless communication,this same technology aims to offer uninterrupted access to different wireless systems like Radio Communication,Bluetooth,and Wi-Fi to achieve better network connection which in turn gives the best quality of service(QoS).Many analysts have established many handover decision systems(HDS)to enable assured continuous mobility between various radio access technologies.Unbrokenmobility is one of themost significant problems considered in wireless communication networks.Each application needs a distinct QoS,so the network choice may shift appropriately.To achieve this objective and to choose the finest networks,it is important to select a best decision making algorithm that chooses the most effective network for every application that the user requires,dependent on QoS measures.Therefore,the main goal of the proposed system is to provide an enhanced vertical handover(VHO)decision making programby using aMulti-CriteriaFuzzy-Based algorithm to choose the best network.Enhanced Multi-Criteria algorithms and a Fuzzy-Based algorithm is implemented successfully for optimal network selection and also to minimize the probability of false handover.Furthermore,a double packet buffer is utilized to decrease the packet loss by 1.5%and to reduce the number of handovers up to 50%compared to the existing systems.In addition,the network setup has an optimized mobilitymanagement system to supervise the movement of the mobile nodes.
基金supported by the Fundamental Research Funds for the Central Universities(No.FRF-TP-22-063A1)the General Program of the National Natural Science Foundation of China(No.71874099).
文摘This study explores whether manager mobility can influence syndications between private equity(PE)firms by constructing coupling network models.Using data from China’s private equity market from 1993 to 2017,we found that driving forces,resistant forces,and network structure play significant roles in determining resource flows between PE firms.Specifically,driving forces indicate that managers moving from domestic and foreign PE firms to state-owned PE firms are more likely to induce syndications.Furthermore,if the manager is promoted when changing jobs,mobility is likely to enhance the flow of resources.Resistant forces indicate that increased geographical distance reduces syndications.As for the influence of structure,if managers leave PE firms with higher status,they are more likely to induce syndications.This study contributes to the coupling network literature by providing a clarified three-factor framework.By exploring the characteristic of managers in state-owned private equity firms,we specified the syndication theory in China.This study can help private equity firms hire valuable managers and expand syndication networks in practice.
基金the Special Research Fund for the Doctoral Program of Higher Education(No.20050248037)the National Natural Science Foundation of China(No.50779033)
文摘The future generation networks or 4G networks constitute of varied technologies converged over the Internet protocol version 6(IPv6) core. The 4G networks offer varied services over different interfaces to the user nodes. Mobility management in 4G networks is an issue that exists. The handover protocols for mobility management in 4G networks that currently exist, do not consider wireless signal degradation during handover operations. This paper introduces the Noise Resilient Reduced Registration Time Care of Mobile IP(NR RRTC:MIP) protocol for handover management. A handover decision algorithm based on the signal strength measured by the user nodes is considered in the NR RRTC: MIP protocol. A simulation study is discussed in the paper to evaluate the performance of the NR RRTC: MIP protocol. The results obtained from the simulation study prove that the NR RRTC: MIP protocol effectively reduces handover latencies and improves network performance.
基金This work was supported by the National Science Fund for Distinguished Young Scholars of China(No.60725105)the National Basic Research Program of China(No.2009CB320404)the Program for Changjiang Scholars and Innovative Research Team in University(IRT0852).
文摘Proxy mobile Internet protocol version 6(PMIPv6)is a network-based mobility management protocol proposed by Internet Engineering Task Force(IETF),which allows nodes to remain service connectivity while moving around in the IPv6 Internet.PMIPv6 is different from the host-based mobility management protocols(mobile Internet protocol version(MIPv6),hierarchical mobile IPv6(HMIPv6),fast handover for mobile IPv6(FMIPv6),and fast handover in hierarchical mobile IPv6(F-HMIPv6)),whose signaling are transferred among some network entities except mobile node(MN).This paper focuses on the analytical modeling of performance analysis for PMIPv6 and other protocols using IEEE802.16-based wireless metropolitan area networks as the wireless access network.The performances of these protocols are evaluated by some metrics like handover latency,service disruption time,and binding update cost.Numerical results show that PMIPv6 has better performance.
基金supported by National Program on Key Basic Research Project of China(No.2013CB329205)National Natural Science Foundation of China(No.61601432)and Fundamental Research Funds for the Central Universities.
文摘Indoor wireless communication networking has received significant attention along with the growth of indoor data traffic.VLC(Visible Light Communication)as a novel wireless communication technology with the advantages of a high data rate,license-free spectrum and safety provides a practical solution for the indoor high-speed transmission of large data traffic.However,limited coverage is an inherent feature of VLC.In this paper,we propose a novel hybrid VLC-Wi-Fi system that integrates multiple links to achieve an indoor high-speed wide-coverage network combined with multiple access,a multi-path transmission control protocol,mobility management and cell handover.Furthermore,we develop a hybrid network experiment platform,the experimental results of which show that the hybrid VLC-Wi-Fi network outperforms both single VLC and Wi-Fi networks with better coverage and greater network capacity.