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《Digital Communications & Networks》2022,8(5):720-726
Fog Radio Access Network (F-RAN) has been regarded as a promising solution to the alleviation of the ever-increasing traffic burden on current and future wireless networks, for it shifts the caching and computing resources from remote cloud to the network edge. However, it makes wireless networks more vulnerable to security attacks as well. To resolve this issue, in this article, we propose a secure yet trustless Blockchain-based F-RAN (BF-RAN), which allows a massive number of trustless devices to form a large-scale trusted cooperative network by leveraging the key features of blockchain, such as decentralization, tamper-proof, and traceability. The architecture of BF-RAN is first presented. Then, the key technologies, including access control, dynamic resource management, and network deployment are discussed. Finally, challenges and open problems in the BF-RAN are identified. 相似文献
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在下行云接入网络(C-RANs)中,核心网络内基站处理单元(BBU)通过前向回传线路向远端无线电头端(RRH)传输数据,然后RRHs通过无线接入链路转发数据。目前,C-RANs的下行链路的能效是C-RANs的研究热点。为此,对C-RANs下行链路能效进行研究,其目的在于最大下行链路的能效。通过对联合用户分配(UA)、RRH激活、数据率分配和信号预编码约束,建立能效最大化表述式,再利用基于逐次凸二次规划的迭代算法求解混合整数非线性问题。仿真结果表明,提出的联合优化设计提高了C-RANs的能效。 相似文献
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S. A. Paschos M. E. Anagnostou F. N. Afrati 《International Journal of Communication Systems》1993,6(3):151-160
In this paper, multiple-phase deterministic protocols for packet radio networks are introduced and analysed. Two modes of information transfer are considered, namely (a) broadcasting and (b) point-to-point transmission. We explore systematic ways of designing multiple-phase protocols and apply them on Manhattan networks. The proposed protocols are studied primarily from the point of view of throughput efficiency. Delay analysis is also presented. 相似文献
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An architecture for next-generation radio access networks 总被引:1,自引:0,他引:1
With fourth-generation wireless technologies envisioned to provide high bandwidth for content-rich multimedia applications, next-generation mobile communication systems are well poised to lead the technology march. Incumbent with the new technology is the challenge of providing flexible, reconfigurable architectures capable of catering to the dynamics of the network, while providing cost-effective solutions for service providers. In this article we focus on IP-based radio access network architectures for next-generation mobile systems. We provide an insight into wireless mesh-based connectivity for the RAN network elements - using short high-bandwidth links to interconnect the network entities in a multihop mesh network for backhauling traffic to the core. A generic self-similar fractal topology, using optical wireless transmission technology, is described. We study the performance of the architecture and conclude that mesh-based architectures are well suited to provide highly scalable, dynamic radio access networks with carrier-class features at significantly low system costs. 相似文献
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Wisely D. Aghvami H. Gwyn S.L. Zahariadis T. Manner J. Gazis V. Houssos N. Alonistioti N. 《Wireless Communications, IEEE》2003,10(4):26-35
Advances in network architecture, enhancements in signaling protocols, provisioning of end-to-end QoS, worldwide seamless mobility, and flexible service provision are among the major research challenges toward next-generation wireless networks. The integration and interoperability of all these technologies, along with new truly broadband wireless innovations and intelligent user-oriented services will lead toward the so-called 4G wireless networks. In this article we identify the key issues of an innovative transparent IP radio access system that targets 4G networks. 相似文献
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Spectrum sensing and access have been widely investigated in cognitive radio network for the secondary users to efficiently utilize and share the spectrum licensed by the primary user. We propose a cluster‐based adaptive multispectrum sensing and access strategy, in which the secondary users seeking to access the channel can select a set of channels to sense and access with adaptive sensing time. Specifically, the spectrum sensing and access problem is formulated into an optimization problem, which maximizes the utility of the secondary users and ensures sufficient protection of the primary users and the transmitting secondary users from unacceptable interference. Moreover, we explicitly calculate the expected number of channels that are detected to be idle, or being occupied by the primary users, or being occupied by the transmitting secondary users. Spectrum sharing with the primary and transmitting secondary users is accomplished by adapting the transmission power to keep the interference to an acceptable level. Simulation results demonstrate the effectiveness of our proposed sensing and access strategy as well as its advantage over conventional sensing and access methods in terms of improving the achieved throughput and keeping the sensing overhead low. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Javier Carmona‐Murillo José‐Luis González‐Sánchez David Cortés‐Polo Francisco‐Javier Rodríguez‐Pérez 《International Journal of Network Management》2014,24(2):85-100
Over the last few years, mobility management in the Internet has been one of the most active fields in communications. The recent increasing mobile traffic demand is having an important impact on the design of mobile networks and some limitations are arising from traditional network deployments. In order to deal with this new scenario, mobility management network architectures are being redesigned towards a more distributed operation. In this paper, we introduce DM3 (distributed mobility management MPLS), a fully distributed architecture designed to track efficiently the mobility of users in the current paradigm of evolving mobile IP networks. In DM3 architecture, several nodes are distributed in the MPLS‐based access network and the mobile nodes are served by a close‐by mobility anchor. With this operation, we reduce the routing and registration update costs, and provide a low handoff latency with a minimal packet loss rate. Analytical and experimental results are presented to justify the benefits of our proposed architecture. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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As CDMA-based cellular networks mature, the current point-to-point links used in connecting base stations to network controllers evolve to an IP-based radio access network (RAN) for reasons of lower cost due to statistical multiplexing gains, better scalability and reliability, and the projected growth in data applications. In this paper, we study the impact of congestion in a best-effort IP RAN on CDMA cellular voice networks. We propose and evaluate three congestion control mechanisms, admission control, diversity control, and router control, to maximize network capacity while maintaining good voice quality. We first propose two new enhancements to CDMA call admission control that consider a unified view of both IP RAN and air interface resources. Next, we introduce a novel technique called diversity control that exploits the soft-handoff feature of CDMA networks and drops selected frames belonging to multiple soft-handoff legs to gracefully degrade-voice quality during congestion. Finally, we study the impact of router control where an active queue management technique is used to reduce delay and minimize correlated losses. Using simulations of a large mobile network, we show that the three different control mechanisms can help gracefully manage 10-40 percent congestion overload in the IP RAN. 相似文献
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Francis J.C. Elberse A. Gobbi R. Rogl P. Ciancetta M.C. Monogioudis P. Nelson J. 《Selected Areas in Communications, IEEE Journal on》1997,15(8):1488-1497
This paper presents an access-independent network architecture for supporting UMTS service capabilities. The approach is based on an enhanced B-ISDN core network with personal and terminal mobility provided by intelligent network techniques. A physical realization is presented, and the protocols corresponding to the physical interfaces are identified. Protocols are proposed for UMTS mobility and service support, and the impact on the B-UNI and IN interfaces is considered. Reflecting the vision of the ETSI global multimedia mobility (GMM) standardization framework, UMTS service support through non-UMTS access is considered. Consideration of DECT as a UMTS access technology leads to an interworking proposal that presents each DECT terminal to the core network in terms of UMTS functional entities. Access-independent usage of UMTS terminal applications motivates additional interworking in the terminal to encapsulate the access network. The desirability of an access-independent UMTS application programming interface in the terminal is indicated 相似文献
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Yieh-Ran Haung 《Vehicular Technology, IEEE Transactions on》2002,51(6):1330-1337
The Universal Mobile Telecommunications System (UMTS) network consists of a core network (CN) and a UMTS terrestrial radio access network (UTRAN). The UTRAN offers radio access bearer (RAB) services between the user equipment (UE) and the CN to support mobile multimedia applications with different quality of service (QoS) requirements. Depending on the requested QoS, different types of RABs can be established at the request of the CN. The UTRAN then has to establish and maintain the RAB with the requested QoS. We study the queueing of RABs as a means for improving the bandwidth utilization while minimizing the RAB blocking probability. We develop an analytical model to study the performance for UTRAN with queued RABs in terms of RAB blocking probability and average queueing time of queued RABs. From an analytic point of view, the main contribution of this paper is the introduction of a novel recursion for the computation of the performance measures. 相似文献
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Fatemeh Ghods Abraham Fapojuwo Fadhel Ghannouchi 《Wireless Communications and Mobile Computing》2016,16(17):2824-2838
This paper develops a stochastic geometry‐based analytical approach for calculating the throughput reliability of a cloud‐radio access network (C‐RAN) comprising randomly distributed remote radio heads (RRHs) and randomly located users. A tunable distance‐based RRH transmit power control mechanism along with cooperative joint transmissions by the RRHs is employed to achieve power savings and high throughput reliability. The analytical result for the throughput reliability serves as input to analysis of per user achievable average rate and C‐RAN network‐level performance metrics of spectral efficiency and energy efficiency. The analytical results are validated by Monte Carlo simulation results with good agreement, thus confirming the accuracy of the developed analytical approach. The key finding from the analysis is that by carefully tuning the RRH transmit power and cooperation parameter (cluster radius), it is possible to realize a threefold improvement in the energy efficiency along with 108% enhancement in the spectral efficiency of C‐RANs. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Reservation random access (RRA) protocols have been proposed for handling speech and data traffic on packet wireless networks. An interesting property of some RRA protocols is the capability of decoupling the speech access procedure from the data access procedure, so that speech access performances do not depend on actual data load. Frame-based protocols allow one to get the decoupling property easily. In this paper, we present a Markov model for analyzing the performances of frame-based RRA protocols that operate in a microcellular environment with channel errors. In the paper, this model is used for evaluating the performances of centralized RRA protocols, which use retransmissions for handling channel errors. Both in-slot access schemes, in which all the slots can be used for talkspurt setup and for user information transmission, and out-slot access schemes, with a separate reservation channel, are examined. Moreover, we present and analyze a new, stable, centralized RRA protocol, namely centralized-collision resolution access (C-CRA), which is based on collision resolution techniques 相似文献
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Per Kreuger Rebecca Steinert Olof Görnerup Daniel Gillblad 《International Journal of Network Management》2018,28(2)
Managing and balancing load in distributed systems remains a challenging problem in resource management, especially in networked systems where scalability concerns favour distributed and dynamic approaches. Distributed methods can also integrate well with centralised control paradigms if they provide high‐level usage statistics and control interfaces for supporting and deploying centralised policy decisions. We present a general method to compute target values for an arbitrary metric on the local system state and show that autonomous rebalancing actions based on the target values can be used to reliably and robustly improve the balance for metrics based on probabilistic risk estimates. To balance the trade‐off between balancing efficiency and cost, we introduce 2 methods of deriving rebalancing actuations from the computed targets that depend on parameters that directly affects the trade‐off. This enables policy level control of the distributed mechanism based on collected metric statistics from network elements. Evaluation results based on cellular radio access network simulations indicate that load balancing based on probabilistic overload risk metrics provides more robust balancing solutions with fewer handovers compared to a baseline setting based on average load. 相似文献
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This paper presents a signaling architecture for supporting mobility in radio asynchronous transfer mode (ATM) networks. A new concept of mobile software agent, known as ‘representative’, is used for insulating fixed network entities from the effects of user mobility. It is shown that, depending on the physical locations of the mobile terminals, their representatives can be used for distributing the mobility management load within the fixed backbone network. This paper describes a location and a representative management scheme followed by a novel connection caching strategy which is used for implementing a family of low-latency and scalable ATM connection handovers. A prototype implementation of the proposed architecture and the associated experimental results are also presented to demonstrate the feasibility and performance of this agent-based signaling scheme. ©1997 by John Wiley & Sons, Ltd. 相似文献
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Integrating dynamic spectrum access and device‐to‐device via cloud radio access networks and cognitive radio
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Marcelo Antonio Marotta Leonardo Roveda Faganello Maicon Kist Lucas Bondan Juliano Araujo Wickboldt Lisandro Zambenedetti Granville Juergen Rochol Cristiano Bonato Both 《International Journal of Communication Systems》2018,31(11)
Dynamic Spectrum Access (DSA) can be integrated with Device‐to‐Device (D2D) communications to enable the exploitation of unused spectrum portions and to address the spectrum scarcity problem. Spectrum management mechanisms integrated into DSA and D2D allow low‐power communications between User Equipments without interfering with licensed primary users. However, these mechanisms tend to be energy and processing intensive, being unfeasible to implement in User Equipments with strict battery and processing limitations. On the other hand, Cloud Radio Access Networks already leverage the virtually unlimited computing capacity of clouds for baseband processing functions. Thus, in this article, we propose the Cognitive Radio Device‐to‐Device (CRD2D) approach aiming to offload spectrum management functionality to the cloud taking advantage of Cloud Radio Access Networks architecture to support the integration of DSA and D2D. 相似文献
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Morteza Rajabzadeh Hossein Khoshbin 《Wireless Communications and Mobile Computing》2014,14(3):355-365
The deployment of multicarrier code division multiple access as the transmission scheme of the spectrum overlay based cognitive radio (CR) networks faces two challenging issues: (i) the need for spreading codes with arbitrary length and (ii) the interfering effect of the leaked power (due to spectral sidelobes) to the adjacent spectral band used by the primary system. To meet these challenges, we propose two novel complex spreading code sets. For this purpose, a cost function is defined as the ratio of the power leaked to the adjacent primary band to the power transmitted to the band allowed for CR operation. The cost function is shown to be convertible to a trace ratio problem. The two complex spreading code sets are determined by deploying two different standard solutions. The first is the conventional but approximate solution based on generalized eigenvalue decomposition (GEVD) method, and the other is an iterative algorithm that converges to the optimal solution and hence outperforms the GEVD based solution. Simulation results show that by a slight decrease in number of users, the code set yielded by iterative algorithm suppresses the leaked power to almost zero. The applicability of the proposed code sets in different scenarios is discussed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献