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Code, Cache and Deliver on the Move: A Novel Caching Paradigm in Hyper-Dense Small-Cell networks

IEEE TRANSACTIONS ON MOBILE COMPUTING 2017年第3期16卷 675-687页

作者： Poularakis, Konstantinos Tassiulas, Leandros Yale Univ Dept Elect Engn New Haven CT 06520 USA Yale Univ Inst Network Sci New Haven CT 06520 USA

Caching popular content files at small-cell base stations (SBSs) has emerged as a promising technique to meet the overwhelming growth in mobile data demand. Despite the plethora of work in this field, a specific aspect has been overlooked. It is assumed that all users remain stationary during data transfer and therefore a complete copy of the requested file can always be downloaded by the associated SBSs. In this work, we revisit the caching problem in realistic environments where moving users intermittently connect to multiple SBSs encountered at different times. Due to connection duration limits, users may download only parts of the requested files. Requests for files that failed to be delivered on time by the SBSs are redirected to the coexisting macro-cell. We introduce an optimization framework that models user movements via random walks on a Markov chain aimed at minimizing the load of the macro-cell. As the main contribution, we put forward a distributed caching paradigm that leverages user mobility predictions and innovative information-mixing methods based on the principle of network coding. Systematic experiments based on measured traces of human mobility patterns demonstrate that our approach can offload 65 percent more macro-cell traffic than existing caching schemes in realistic settings.

关键词： Content caching human mobility predictability network coding Markov chain model small-cell networks

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BOUNDING THE OPTIMAL RATE OF THE ICSI AND ICCSI PROBLEM

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SIAM JOURNAL ON DISCRETE MATHEMATICS 2017年第2期31卷 1403-1427页

作者： Byrne, Eimear Calderini, Marco Univ Coll Dublin Sch Math & Stat Dublin Ireland Univ Trento Dept Math Povo Italy

In this work we study both the index coding with side information (ICSI) problem introduced by Birk and Kol in 1998 and the more general problem of index coding with coded side information (ICCSI), described by Shum et al. in 2012. We estimate the optimal rate of an instance of the index coding problem. In the ICSI problem case, we characterize those digraphs having min rank one less than their order and we give an upper bound on the min-rank of a hypergraph whose incidence matrix can be associated with that of a 2-design. Security aspects are discussed in the particular case when the design is a projective plane. For the coded side information case, we extend the graph theoretic upper bounds given by Shanmugam et al. in 2014 on the optimal rate of index code.

关键词： index coding network coding coded side information broadcast with side information min-rank

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Error Correction for Index coding With Coded Side Information

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IEEE TRANSACTIONS ON INFORMATION THEORY 2017年第6期63卷 3712-3728页

作者： Byrne, Eimear Calderini, Marco Univ Coll Dublin Sch Math & Stat Res Innovat & Impact Dublin Ireland Univ Trento Dept Math Trento Italy

Index coding is a source coding problem in which a broadcaster seeks to meet the different demands of several users, each of whom is assumed to have some prior information on the data held by the sender. A well-known application is satellite communications, as described in one of the earliest papers on the subject (Birk and Kol, 1998). It is readily seen that if the sender has knowledge of its clients' requests and their side-information sets, then the number of packet transmissions required to satisfy all users' demands can be greatly reduced if the data are encoded before sending. The collection of side-information indices as well as the indices of the requested data is described as an instance I of the index coding with side-information (ICSI) problem. The encoding function is called the index code of I, and the number of transmissions, resulting from the encoding is referred to as its length. The main ICSI problem is to determine the optimal length of an index code and instance I. As this number is hard to compute, bounds approximating it are sought, as are algorithms to compute efficient index codes. These questions have been addressed by several authors (e.g., see Alon et al. 2008, Bar-Yossef et al. 2011, Blasiak et al. 2013), often taking a graph-theoretic approach. Two interesting generalizations of the problem that have appeared in the literature are the subject of this paper. The first of these is the case of index coding with coded side information (Dai et al. 2014), in which linear combinations of the source data are both requested by and held as users' side-information. This generalization has applications, for example, to relay channels and necessitates algebraic rather than combinatorial methods. The second is the introduction of error-correction in the problem, in which the broadcast channel is subject to noise (Dau et al. 2013). In this paper, we characterize the optimal length of a scalar or vector linear index code with coded side information (ICC

关键词： Index coding min-rank error correction minimum distance network coding coded side information

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${\mathsf{ENCLOSE}}$: An Enhanced Wireless Interface for Communication in Factory Automation networks

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IEEE Transactions on Industrial Informatics 2018年第12期14卷 5346-5358页

作者： Adnan Aijaz Telecommunications Research Laboratory Toshiba Research Europe Ltd. Bristol U.K.

Wireless technologies are increasingly gaining popularity for many industrial automation applications. State-of-the-art wireless technologies mainly support monitoring and open-loop control applications at the lowest level of the automation pyramid. The use of wireless technologies for closed-loop control applications is still in infancy. This paper proposes a novel wireless solution, termed as ENCLOSE, for closed-loop control applications at the sensor/actuator level of factory automation. At the Physical layer, ENCLOSE adopts IEEE 802.15.1 specifications with an enhanced data rate feature. The medium access control layer of ENCLOSE is based on time-division multiple access and frequency-division duplexing. ENCLOSE is based on an optimized frame structure for achieving low latency while accounting for the peculiarities of closed-loop control. Moreover, ENCLOSE implements two different cooperative multi-user diversity techniques for achieving high reliability. Performance evaluation, based on comprehensive analytical modeling and system-level simulation studies, demonstrates that ENCLOSE provides a practical solution, that fulfils the stringent requirements of closed-loop control applications in factory automation environments.

关键词： Wireless communication Manufacturing automation network coding Bluetooth IEEE 802.15 Standard Actuators Closed loop systems

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Low Delay Random Linear coding and Scheduling Over Multiple Interfaces

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2017年第11期16卷 3100-3114页

作者： Garcia-Saavedra, Andres Karzand, Mohammad Leith, Douglas J. NEC Labs Europe D-69115 Heidelberg Germany Trinity Coll Dublin Dublin 2 Ireland

High-performance real-time applications, expected to be of importance in the upcoming 5G era, such as virtual and augmented reality or tele-presence, have stringent requirements on throughput and per-packet in-order delivery delay. Use of multipath transport is gaining momentum for supporting these applications. However, building an efficient, low latency multipath transfer mechanism remains highly challenging. The primary reason for this is that the delivery delay along each path is typically uncertain and time-varying. When the transmitter ignores the stochastic nature of the path delays, then packets sent along different paths frequently arrive out of order and need to be buffered at the receiver to allow in-order delivery to the application. In this paper, we propose Stochastic Earliest Delivery Path First (S-EDPF), a generalization of EDPF which takes into account uncertainty and time-variation in path delays yet has low-complexity suited to practical implementation. Moreover, we integrate a novel low-delay Forward Error Correction (FEC) scheme into S-EDPF in a principled manner by deriving the optimal schedule for coded packets across multiple paths. Finally, we demonstrate, both analytically and empirically, that S-EDPF is effective at mitigating the delay impact of reordering and loss in multipath transport protocols, offering substantial performance gains over the state of the art.

关键词： Low-delay communications stochastic scheduling network coding multipath transport tactile internet

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An Enhanced Paradigm for Cognitive Cooperation networks: Two-to-One Energy and Spectrum Dual-Cooperation

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SENSORS 2018年第7期18卷 2085-2085页

作者： Liu, Zhihui Xu, Wenjun Wang, Junyi Dong, Tao Qiu, Hongbing Beijing Inst Satellite Informat Engn State Key Lab Space Ground Integrated Informat Te Beijing 100095 Peoples R China Beijing Univ Posts & Telecommun Minist Educ Key Lab Universal Wireless Commun Beijing 100876 Peoples R China Guilin Univ Elect Technol Guangxi Key Lab Wireless Wideband Commun & Signal Guilin 541004 Peoples R China

In this paper, two-to-one energy and spectrum dual-cooperation (ESDC) is investigated for cognitive cooperation networks. Specifically, the energy and spectrum of two primary users (PUs) are both transferred or authorized to one multi-antenna secondary user (SU) in exchange for its aid in the signal relaying to guarantee the successful data transmission, whilst the SU, which originally owns no spectrum access privilege and limited energy storage, is also able to concurrently transmit its own data through spatial multiplexing. Moreover, network-coding is also adopted to further compress the data size and hence reduce the power consumption at SU. The formulated problem for the aforementioned two-to-one ESDC model is non-convex and intractable to solve directly. To solve the problem effectively, the Lagrangian dual methods plus fixed-point iteration methods and semidefinite relation methods are employed, and the optimal solution could be achieved through iterative optimization. Simulation results show that, compared with the traditional spectrum-only cooperation, the proposed two-to-one ESDC paradigms can greatly improve the successful transmission probability for PUs and achievable transmission rate for SU. Meanwhile, the proposed two-to-one dual-cooperation modes are significantly superior to the one-to-one cooperation mode, in terms of spectrum efficiency and energy efficiency.

关键词： energy and spectrum dual-cooperation cognitive cooperation networks spatial multiplexing network coding

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Routing Strategy and Data Security Technology in IPv6 Wireless Sensor networks

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INTERNATIONAL JOURNAL OF ONLINE ENGINEERING 2018年第8期14卷 94-106页

作者： Li, Zhaoyan Zhao, Chengfang Xihua Univ Sch Comp & Software Engn Chengdu 610039 Sichuan Peoples R China

A new routing rule detection and identity authentication mechanism based on the path sequence is proposed to cope with the vulnerability problem of wireless sensor networks (WSNs) against various attacks, especially in unattended environments. Then, the great permutation encryption algorithm (G-PEC) for WSN is proposed. Finally, a signature scheme against pollution attack based on linear network coding is improved. The results show that the proposed path sequence-based authentication method with the Contiki simulation platform can significantly reduce the computing overhead of sensor nodes and decrease the energy consumption and delay of nodes to a greater extent than the traditional authentication method. The G-PEC can effectively resist eavesdropping attack, and the new signature scheme does not need additional secure channels. The proposed mechanism also provides source message authentication.

关键词： wireless sensor network routing authentication network coding permutation encryption homomorphic function

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Distributed Decode-Forward for Relay networks

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IEEE TRANSACTIONS ON INFORMATION THEORY 2017年第7期63卷 4103-4118页

作者： Lim, Sung Hoon Kim, Kwang Taik Kim, Young-Han Korea Inst Ocean Sci & Technol Ansan 15627 South Korea Samsung Elect Suwon 16677 South Korea Univ Calif San Diego Dept Elect & Comp Engn La Jolla CA 92093 USA

A new coding scheme for general N-node relay networks is presented for unicast, multicast, and broadcast. The proposed distributed decode-forward scheme combines and generalizes Marton coding for single-hop broadcast channels and the Cover-El Gamal partial decode-forward coding scheme for three-node relay channels. The key idea of the scheme is to precode all the codewords of the entire network at the source by multicoding over multiple blocks. This encoding step allows these codewords to carry partial information of the messages implicitly without complicated rate splitting and routing. This partial information is then recovered at the relay nodes and forwarded further. For N-node Gaussian unicast, multicast, and broadcast relay networks, the scheme achieves within 0.5N bits from the cutset bound, and thus from the capacity (region), regardless of the network topology, channel gains, or power constraints. Roughly speaking, distributed decode-forward is dual to noisy network coding, which generalized compress-forward to unicast, multicast, and multiple access relay networks.

关键词： Decode-forward discrete memoryless network Gaussian network network coding relaying capacity

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Improving Secrecy Outage and Throughput Performance in Two-Way Energy-Constraint Relaying networks Under Physical Layer Security

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WIRELESS PERSONAL COMMUNICATIONS 2017年第4期96卷 6425-6457页

作者： Sang Quang Nguyen Kong, Hyung Yun Duy Tan Univ FEEE Res Ctr New Technol NewTech Da Nang Vietnam Univ Ulsan Sch Elect Engn Ulsan South Korea

In this paper, we propose three secrecy cooperative transmission protocols for a two-way energy-constrained relaying network in which two sources wish to exchange information with the help of multiple intermediate relays being subjected to wiretapping by multiple eavesdroppers. In the secure two-way communication (STW protocol), an energy-constrained relay is preselected via one of three investigated relay-selection strategies, which harvest the energy from the radio-frequency signals of one source and decode-and-forward the signals to another source. In secure two-way communication with network coding (STWNC protocol), the network coding technique is applied at a relay preselected via one of two investigated relay-selection strategies. In secure two-way communication with cooperative jamming and network coding (STWJNC protocol), under cooperative jamming, the network coding technique is applied at two sources and a preselected relay where a jammer-relay pair is preselected via one of two investigated selection strategies. The power-splitting receiver is applied at the energy-constrained relay for all proposed protocols. To evaluate performance, we derive new closed-form expressions for the secrecy outage probability and the throughput performance of the three protocols with the different relay and jammer-selection strategies. Our analysis is verified using Monte Carlo simulations.

关键词： Energy harvesting Two-way communication Physical layer security Relay selection network coding Cooperative jamming

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Optimizing network performance with multihoming and network coding

Optimizing network performance with multihoming and network ...

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IEEE Globecom Workshops

作者： Nelson Capela Susana Sargento Instituto de Telecomunicações Universidade de Aveiro Aveiro Portugal

The evolution of wireless access technologies, the increasing demand of users and services, and the evolution of terminals (which have the ability to connect to different access technologies), strengthened the need to use all the available resources in an optimal way. This paper presents a new approach that uses the combination of multihoming and network coding to improve the allocation of network resources and the communication performance in heterogeneous technologies. We developed a model to determine the optimal allocation of traffic flows through different paths in a multihoming environment with network coding. Then, considering different technologies (Wi-Fi and HSDPA as examples), we modelled the system performance and analyzed the best configuration for both multihoming and network coding, as a function of the user, services and network characteristics. The results, obtained both through analytical and real experiments, show the advantages of multihoming, how it shall be configured in an optimal way, and the impact of network coding and its parameters in the network performance.

关键词： Delay Throughput IEEE 802.11 Standards network coding Multiaccess communication Spread spectrum communication Analytical models

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