Showing papers in "IEICE Transactions on Communications in 2019"

Proactive Failure Detection Learning Generation Patterns of Large-Scale Network Logs

Abstract: With the growth of services in IP networks, network operators are required to perform proactive operation that quickly detects the signs of critical failures and prevents future problems. Network log data, including router syslog, are rich sources for such operations. However, it has become impossible to find genuinely important logs that lead to serious problems due to the large volume and complexity of log data. We propose a log analysis system for proactive detection of failures. Our key observation is that the abnormality of logs depends on not just the keywords in the messages (e.g. ERROR, FAIL), but generation patterns such as burstiness. Our system consists of three functions: (i) extracting log templates automatically and quickly from a massive amount of unstructured log data; (ii) constructing log feature vectors to characterize the generation patterns of logs; and (iii) using a supervised machine learning approach to associate failures with the log data that appeared before them. We validated our system using real log data collected from a large network and determined its effectiveness.

Comprehensive Survey of IPv6 Transition Technologies: A Subjective Classification for Security Analysis

Abstract: Due to the depletion of the public IPv4 address pool, the transition to IPv6 became inevitable. However, this ongoing transition is taking a long time, and the two incompatible versions of the Internet Protocol must coexist. Different IPv6 transition technologies were developed, which can be used to enable communication in various scenarios, but they also involve additional security issues. In this paper, first, we introduce our methodology for analyzing the security of IPv6 transition technologies in a nutshell. Then, we develop a priority classification method for the ranking of different IPv6 transition technologies and their most important implementations, so that the vulnerabilities of the most crucial ones may be examined first. Next, we conduct a comprehensive survey of the existing IPv6 transition technologies by describing their application scenarios and the basics of their operation and we also determine the priorities of their security analysis according to our ranking system. Finally, we show that those IPv6 transition technologies that we gave high priorities, cover the most relevant scenarios. key words: IPv6 transition technologies, network security, survey

Assessing Lightweight Virtualization for Security-as-a-Service at the Network Edge

Abstract: Accounting for the exponential increase of security threats, the development of new defense strategies for pervasive environments is acquiring an even growing importance. The expected avalanche of heterogeneous IoT devices which will populate our industrial factories and houses will increase the complexity of managing security requirements in a comprehensive way. To this aim, cloud-based security services are gaining notable impetus to provide security mechanisms according to Security-as-a-Service (SECaaS) model. However, the deployment of security applications in remote cloud data-centers can introduce several drawbacks in terms of traffic overhead and latency increase. To cope with this, edge computing can provide remarkable advantages avoiding long routing detours. On the other hand, the reduced capabilities of edge node introduce potential constraints in the overall management. This paper focuses on the provisioning of virtualized security services in resource-constrained edge nodes by leveraging lightweight virtualization technologies. Our analysis aims at shedding light on the feasibility of container-based security solutions, thus providing useful guidelines towards the orchestration of security at the edge.

Recent Activities of 5G Experimental Trials on Massive MIMO Technologies and 5G System Trials Toward New Services Creation

Abstract: In order to cope with recent growth of mobile data traffic and emerging various services, world-wide system trials for the fifthgeneration (5G) mobile communication system that dramatically extends capability of the fourth-generation mobile communication system are being performed to launch its commercial service in 2020. In addition, research and development of new radio access technologies for 5G evolution and beyond 5G systems are beginning to be made all over the world. This paper introduces our recent activities on 5G transmission experiments that aim to validate Massive MIMO technologies using higher frequency bands such as SHF/EHF bands, that is, 5G experimental trials. Recent results of 5G system trials to create new services and applications in 5G era in cooperation with partners in vertical industries are also introduced. key words: fifth generation mobile communication system, radio access technology, higher frequency band, experimental trial, system trial

Field Trial on 5G Low Latency Radio Communication System Towards Application to Truck Platooning

Abstract: The fifth generation mobile communication system (5G) is designed to have new radio capabilities to support not only conventional enhanced Mobile Broadband (eMBB) communications but also new machine type communications such as Ultra-Reliable Low-Latency communications (URLLC) and massive Machine Type communications (m-MTC). In such new areas of URLLC and m-MTC, mobile operators need to explore new use cases and/or applications together with vertical industries, the industries which are potential users of 5G, in order to fully exploit the new 5G capabilities. Intelligent Transport System (ITS), including automated driving, is one of the most promising application areas of 5G since it requires both ultra-reliable and low-latency communications. We are actively working on the research and development of truck platooning as a new 5G application. We have developed a field trial system for vehicular-to-network (V2N) communications using 5G prototype equipment and actual largesize trucks in order to assess 5G capabilities, including ultra-low-latency, in automotive test courses in the field. This paper discusses the fundamental performance evaluation required for vehicular communications between platooning trucks, such as low-latency message communication for vehicle control and low-latency video monitoring of following platooning truck vehicles. The paper also addresses the field evaluation results of 5G V2N communications in a rural area. It clarifies the fundamental radio propagation issues at the leading and the following vehicles in truck platooning for V2N communications, and discusses the impact of the radio propagation over a road to the over-the-air transmission performance of 5G V2N communications. key words: 5G, low latency, truck platooning, field trial

Design of Criterion for Adaptively Scaled Belief in Iterative Large MIMO Detection

Abstract: This paper proposes a new design criterion of adaptively scaled belief (ASB) in Gaussian belief propagation (GaBP) for large multiuser multi-input multi-output (MU-MIMO) detection. In practical MU detection (MUD) scenarios, the most vital issue for improving the convergence property of GaBP iterative detection is how to deal with belief outliers in each iteration. Such outliers are caused by modeling errors due to the fact that the law of large number does not work well when it is difficult to satisfy the large system limit. One of the simplest ways to mitigate the harmful impact of outliers is belief scaling. A typical approach for determining the scaling parameter for the belief is to create a look-up table (LUT) based on the received signal-to-noise ratio (SNR) through computer simulations. However, the instantaneous SNR differs among beliefs because the MIMO channels in the MUD problem are random; hence, the creation of LUT is infeasible. To stabilize the dynamics of the random MIMO channels, we propose a new transmission block based criterion that adapts belief scaling to the instantaneous channel state. Finally, we verify the validity of ASB in terms of the suppression of the bit error rate (BER) floor. key words: multi-user multi-input multi-output (MU-MIMO), Gaussian belief propagation (GaBP), iterative detection, soft interference cancellation, adaptive belief scaling

Network Resonance Method: Estimating Network Structure from the Resonance of Oscillation Dynamics

Abstract: Spectral graph theory, based on the adjacency matrix or the Laplacian matrix that represents the network topology and link weights, provides a useful approach for analyzing network structure. However, in large scale and complex social networks, since it is difficult to completely know the network topology and link weights, we cannot determine the components of these matrices directly. To solve this problem, we propose a method for indirectly determining the Laplacian matrix by estimating its eigenvalues and eigenvectors using the resonance of oscillation dynamics on networks. key words: Laplacian matrix, spectral graph theory, resonance

Cefore: Software Platform Enabling Content-Centric Networking and Beyond

Abstract: Information-Centric or Content-Centric Networking (ICN/CCN) is a promising novel network architecture that naturally integrates in-network caching, multicast, and multipath capabilities, without relying on centralized application-specific servers. Software platforms are vital for researching ICN/CCN; however, existing platforms lack a focus on extensibility and lightweight implementation. In this paper, we introduce a newly developed software platform enabling CCN, named Cefore. In brief, Cefore is lightweight, with the ability to run even on top of a resourceconstrained device, but is also easily extensible with arbitrary plugin libraries or external software implementations. For large-scale experiments, a network emulator (Cefore-Emu) and network simulator (Cefore-Sim) have also been developed for this platform. Both Cefore-Emu and Cefore-Sim support hybrid experimental environments that incorporate physical networks into the emulated/simulated networks. In this paper, we describe the design, specification, and usage of Cefore as well as Cefore-Emu and Cefore-Sim. We show performance evaluations of in-network caching and streaming on Cefore-Emu and content fetching on Cefore-Sim, verifying the salient features of the Cefore software platform. key words: ICN, CCN, in-network cache, computing in network, Cefore, open source

Transferring Adaptive Bit Rate Streaming Quality Models from H.264/HD to H.265/4K-UHD

Abstract: In this paper the quality of adaptive bit rate video streaming is investigated and two state-of-the-art models, i.e., the NTT audiovisual quality-estimation and ITU-T P.1203 models, are considered. This paper shows how these models can be applied to new conditions, e.g., 4K ultra high definition (4K-UHD) videos encoded using H.265, considering that they were originally designed and trained for HD videos encoded with H.264. Six subjective evaluations involving up to 192 participants and a large variety of test conditions, e.g., durations from 10 sec to 3min, codingquality variation, and stalling events, were conducted on bothTVandmobile devices. Using the subjective data, this paper addresses how models and coefficients can be transferred to new conditions. A comparison between state-of-the-art models is conducted, showing the performance of transferred and retrained models. It is found that other video-quality estimation models, such as VMAF, can be used as input of the NTT and ITU-T P.1203 long-term pooling modules, allowing these other video-quality-estimation models to support the specificities of adaptive bit-rate-streaming scenarios. Finally, all retrained coefficients are detailed in this paper allowing future work to directly reuse the results of this study. key words: quality of experience, adaptive bit rate streaming, audiovisualquality-estimation models, subjective, monitoring, stalling

Comprehensive Performance Evaluation of Universal Time-Domain Windowed OFDM-Based LTE Downlink System

Abstract: A variety of all-new systems such as a massive machine type communication (mMTC) system will be supported in 5G and beyond. Although eachmMTCdevice occupies quite narrow bandwidth, themassive number of devices expected will generate a vast array of traffic and consume enormous spectrum resources. Therefore, it is necessary to proactively gather up and exploit fractional spectrum resources including guard bands that are secured but unused by the existing Long Term Evolution (LTE) systems. The guard band is originally secured as a margin for high out-of-band emission (OOBE) caused by the discontinuity between successive symbols in the cyclic prefix-based orthogonal frequency division multiplexing (CPOFDM), and new-waveforms enabling high OOBE suppression have been widely researched to efficiently allocate narrowband communication to the frequency gap. Time-domain windowing is a well-known signal processing technique for reducing OOBE with low complexity and a universal timedomain windowed OFDM (UTW-OFDM) with a long transition duration exceeding the CP length has demonstrated its ability in WLAN-based systems. In this paper, we apply UTW-OFDM to the LTE downlink system and comprehensively evaluate its performance under the channel models defined by 3GPP. Specifically, we evaluate OOBE reduction and block error rate (BLER) by computer simulation and clarify how far OOBE can be reduced without degrading communication quality. Furthermore, we estimate the implementation complexity of the proposed UTW-OFDM, the conventional CP-OFDM, and the universal filtered-OFDM (UF-OFDM) by calculating the number of required multiplications. These evaluation and estimation results demonstrate that the proposed UTW-OFDM is a practical new-waveform applicable to the 5G and beyond. key words: CP-OFDM, UTW-OFDM, time-domain windowing, LTE, outof-band emission (OOBE), block error rate (BLER), complexity

Improved Optical Amplification Efficiency by Using Turbo Cladding Pumping Scheme for Multicore Fiber Optical Networks

Abstract: We realize a multicore erbium-doped fiber amplifier (MCEDFA)with 2 dB optical gain improvement (average) by recycling the residual 0.98 μm pump light from the MC-EDF output. Eight-channel per core wavelength division multiplexed (WDM) Nyquist PM-16QAM optical signal amplification is demonstrated over a 40-minute period. Furthermore, we demonstrate the proposed MC-EDFA’s stability by using it to amplify a Nyquist PM-16QAM signal and evaluating the resulting Q-factor variation. We found that our scheme contributes to reducing the total power consumption of MC-EDFAs in spatial division multiplexing (SDM)/WDM networks by up to 33.5%. key words: multicore-EDFA, cladding pumping, recycle, power consumption

Electromagnetic Absorber Made by Natural Rubber

Abstract: This paper proposes fabrication process of a pyramidal electromagnetic (EM) absorber made by natural rubber. The advantage of this research is to generate value-added latex from Thai rubber and to reduce number of chemical absorber by using natural rubber based absorber. The proposed absorber in the research is mainly made from latex with carbon black filler. The proposed absorber is in the form of rubber foam which provides suitable characteristics to serve as an EM absorber. The results of this research are chemical formulas for fabrication of pyramidal rubber foam with carbon black filler. The fabrication cost is very low when compared to an available commercial absorber. The electrical properties of the proposed EM absorber are measured. Also the reflectivity is measured and compared well with a commercial EM absorber. key words: electromagnetic absorber, natural rubber, latex, rubber foams, absorption

12- and 21-GHz Dual-Band Dual-Circularly Polarized Offset Parabolic Reflector Antenna Fed by Microstrip Antenna Arrays for Satellite Broadcasting Reception

Abstract: In December 2018, satellite broadcasting for 4K/8K ultrahigh-definition television (UHDTV) will begin in Japan. It will be provided in the 12-GHz (11.7 to 12.75GHz) band with rightand left-hand circular polarizations. BSAT-4a, a satellite used for broadcasting UHDTV, was successfully launched in September 2017. This satellite has not only 12GHz-band rightand left-hand circular polarization transponders but also a 21-GHz-band experimental transponder. The 21-GHz (21.4 to 22.0GHz) band has been allocated as the downlink for broadcasting satellite service in ITU-R Regions 1 (Europe, Africa) and 3 (Asia Pacific). To receive services provided over these two frequency bands and with dual-polarization, we implement and evaluated a dual-band and dual-circularly polarized parabolic reflector antenna fed by 12and 21-GHz-band microstrip antenna arrays with a multilayer structure. The antenna is used to receive 12and 21GHz-band signals from in-orbit satellites. The measured and experimental results prove that the proposed antenna performs as a dual-polarized antenna in those two frequency bands and has sufficient performance to receive satellite broadcasts. key words: reflector antenna, microstrip antenna, circular polarization, dual band antenna, dual polarized antenna

Introduction to Electromagnetic Information Security

Abstract: With the rising importance of information security, the necessity of implementing better security measures in the physical layer as well as the upper layers is becoming increasing apparent. Given the development of more accurate and less expensive measurement devices, highperformance computers, and larger storage devices, the threat of advanced attacks at the physical level has expanded from the military and governmental spheres to commercial products. In this paper, we review the issue of information security degradation through electromagnetic (EM)-based compromising of security measures in the physical layer (i.e., EM information security). Owing to the invisibility of EM radiation, such attacks can be serious threats. We first introduce the mechanism of information leakage through EM radiation and interference and then present possible countermeasures. Finally, we explain the latest research and standardization trends related to EM information security. key words: EM information security, TEMPEST, side-channel attacks, fault analysis, hardware Trojan horse, electromagnetic compatibility

Design and Evaluation of Information Bottleneck LDPC Decoders for Digital Signal Processors

Abstract: Receiver implementations with very low quantization resolution will play an important role in 5G, as high precision quantization and signal processing are costly in terms of computational resources and chip area. Therefore, low resolution receivers with quasi optimum performance will be required to meet complexity and latency constraints. The Information Bottleneck method allows for a novel, information centric approach to design such receivers. The method was originally introduced by Naftali Tishby et al. and mostly used in the machine learning field so far. Interestingly, it can also be applied to build surprisingly good digital communication receivers which work fundamentally different than stateof-the-art receivers. Instead of minimizing the quantization error, receiver components with maximum preservation of relevant information for a given bit width can be designed. All signal processing in the resulting receivers is performed using only simple lookup operations. In this paper, we first provide a brief introduction to the design of receiver components with the Information Bottleneck method. We keep referring to decoding of lowdensity parity-check codes as a practical example. The focus of the paper lies on practical decoder implementations on a digital signal processor which illustrate the potential of the proposed technique. An Information Bottleneck decoder with 4 bit message passing decoding is found to outperform 8 bit implementations of the well-known min-sum decoder in terms of bit error rate and to perform extremely close to an 8 bit belief propagation decoder, while offering considerably higher net decoding throughput than both conventional decoders. key words: mutual information, channel decoding, quantization, information bottleneck method

Medical Healthcare Network Platform and Big Data Analysis Based on Integrated ICT and Data Science with Regulatory Science

Abstract: This paper provides perspectives for future medical healthcare social services and businesses that integrate advanced information and communication technology (ICT) and data science. First, we propose a universal medical healthcare platform that consists of wireless body area network (BAN), cloud network and edge computer, big data mining server and repository with machine learning. Technical aspects of the platform are discussed, including the requirements of reliability, safety and security, i.e., so-called dependability. In addition, novel technologies for satisfying the requirements are introduced. Then primary uses of the platform for personalized medicine and regulatory compliance, and its secondary uses for commercial business and sustainable operation are discussed. We are aiming at operate the universal medical healthcare platform, which is based on the principle of regulatory science, regionally and globally. In this paper, trials carried out in Kanagawa, Japan and Oulu, Finland will be revealed to illustrate a future medical healthcare social infrastructure by expanding it to Asia-Pacific, Europe and the rest of the world. We are representing the activities of Kanagawa medical device regulatory science center and a joint proposal on security in the dependable medical healthcare platform. Novel schemes of ubiquitous rehabilitation based on analyses of the training effect by remote monitoring of activities and machine learning of patient’s electrocardiography (ECG) with a neural network are proposed and briefly investigated. key words: medical ICT, body area network (BAN), medical healthcare, big data, machine learning, dependability, regulatory science

Inferring Latent Traffic Demand Offered to an Overloaded Link with Modeling QoS-Degradation Effect

Abstract: In this paper, we propose a CTRIL (Common Trend and Regression with Independent Loss) model to infer latent traffic demand in overloaded links as well as how much it is reduced due to QoS (Quality of Service) degradation. To appropriately provision link bandwidth for such overloaded links, we need to infer how much traffic will increase without QoS degradation. Because original latent traffic demand cannot be observed, we propose a method that compares the other traffic time series of an underloaded link, and by assuming that the latent traffic demands in both overloaded and underloaded are common, and actualized traffic demand in the overloaded link is decreased from common pattern due to the effect of QoS degradation. To realize the method, we developed a CTRILmodel on the basis of a state-space model where observed traffic is generated from a latent trend but is decreased by the QoS degradation. By applying the CTRILmodel to actual HTTP (Hypertext transfer protocol) traffic and QoS time series data, we reveal that 1% packet loss decreases traffic demand by 12.3%, and the estimated latent traffic demand is larger than the observed one by 23.0%. key words: latent traffic demand, engagement, state space model

On the Bit Error Probability of OFDM and FBMC-OQAM Systems in Rayleigh and Rician Multipath Fading Channels

Abstract: Filter bank multicarrier with offset quadrature amplitude modulation (FBMC-OQAM) is considered an alternative to conventional orthogonal frequency division multiplexing (OFDM) to meet the various requirements proposed by future communication networks. Among the different perspectives on the merits of FBMC-OQAM and OFDM, a straightforward metric is the bit error probability (BEP). This paper presents a general analytical framework for BEP evaluation that is applicable to FBMCOQAM and OFDM systems in both Rayleigh and Rician multipath fading channels. Explicit BEP expressions are derived for Gray-coded pulse amplitude modulation (PAM) and square quadrature amplitude modulation (QAM) signals with arbitrary constellation sizes. The theoretical analysis results show excellent agreement with the numerical simulation results in different channel scenarios. key words: bit error probability, FBMC-OQAM, OFDM, multipath channel, Gray coding

Controller Area Network and Its Reduced Wiring Technology

Abstract: Controller area network (CAN) has been widely adopted as an in-vehicle communications standard. CAN with flexible data-rate (CAN FD) is defined in the ISO standards to achieve higher data rates than the legacy CAN. A number of CAN nodes can be connected by a single transmission medium, i.e. CAN enables us to constitute cost-effective bustopology networks. CAN puts carrier sense multiple access with collision resolution (CSMA/CR) into practice by using bit-wise arbitration based on wired logical AND in the physical layer. The most prioritized message is delivered without interruption if two or more CAN nodes transmit messages at the same time due to the bit-wise arbitration. However, the scalability of CAN networks suffers from ringing caused by the signaling mechanism establishing the wired logical AND.We need to reduce networking material in a car in order to reduce the car weight, save the fuel and the cost, and develop a sustainable society by establishing more scalable CAN networks. In this paper, we show a reduced wiring technology for CAN to enhance the network scalability and the cost efficiency. key words: CAN, CAN FD, bus topology, CSMA/CR, wired logical AND, bit-wise arbitration, ringing, reduced wiring

Overflows in Multiservice Systems

Abstract: This article presents a universal and versatile model of multiservice overflow systems based on Hayward’s concept. The model can be used to analyzemodern telecommunications and computer networks, mobile networks in particular. The advantage of the proposed approach lies in its ability to analyze overflow systems with elastic and adaptive traffic, systems with distributed resources and systems with non-full-availability in primary and secondary resources. key words: multiservice traffic, overflow system, elastic traffic, adaptive traffic, distributed systems