[서평]「Component Software」 - Beyond Object-Oriented Programming -

The exponential growth and availability of data in all forms is the main booster to the continuing evolution in the communications industry. The popularization of traffic-intensive applications including high definition video, 3-D visualization, augmented reality, wearable devices, and cloud computing defines a new era of mobile communications. The immense amount of traffic generated by today’s customers requires a paradigm shift in all aspects of mobile networks. Ultradense network (UDN) is one of the leading ideas in this racetrack. In UDNs, the access nodes and/or the number of communication links per unit area are densified. In this paper, we provide a survey-style introduction to dense small cell networks. Moreover, we summarize and compare some of the recent achievements and research findings. We discuss the modeling techniques and the performance metrics widely used to model problems in UDN. Also, we present the enabling technologies for network densification in order to understand the state-of-the-art. We consider many research directions in this survey, namely, user association, interference management, energy efficiency, spectrum sharing, resource management, scheduling, backhauling, propagation modeling, and the economics of UDN deployment. Finally, we discuss the challenges and open problems to the researchers in the field or newcomers who aim to conduct research in this interesting and active area of research.

Ultra-Dense Networks: A Survey

To support bursty traffic on the Internet (and especially WWW) efficiently, optical burst switching (OBS) is proposed as a way to streamline both protocols and hardware in building the future gener...

Optical burst switching (OBS) - a new paradigm for an optical Internet

https://onlinelibrary.wiley.com/doi/pdf/10.1002/stvr.247

Problem frames: analyzing and structuring software development problems. By Michael Jackson. Published by Addison‐Wesley, Boston, Massachusetts, U.S.A., ACM Press Series, 2001. ISBN: 0‐201‐59627‐X, 390 pages. Price: U.K. ?32.95, U.S.A. $49.99, soft cover.

Machine learning algorithms for wireless sensor networks: A survey

Orthogonal Frequency Division Multiplexing Access (OFDMA) has been increasingly deployed in various emerging and evolving cellular systems to reduce interference and improve overall system performance. However, in these systems Inter-Cell Interference (ICI) still poses a real challenge that limits the system performance, especially for users located at the cell edge. Inter-cell interference coordination (ICIC) has been investigated as an approach to alleviate the impact of interference and improve performance in OFDMA-based systems. A common ICIC technique is interference avoidance in which the allocation of the various system resources (e.g., time, frequency, and power) to users is controlled to ensure that the ICI remains within acceptable limits. This paper surveys the various ICIC avoidance schemes in the downlink of OFDMA-based cellular networks. In particular, the paper introduces new parameterized classifications and makes use of these classifications to categorize and review various static (frequency reuse-based) and dynamic (cell coordination-based) ICIC schemes.

/pdf/a-survey-on-inter-cell-interference-coordination-techniques-nafauc311u.pdf

A Survey on Inter-Cell Interference Coordination Techniques in OFDMA-Based Cellular Networks

Coverage in mobile wireless sensor networks (M-WSN)

All-optical wavelength division multiplexing (WDM) networks are expected to realize the potential of optical technologies to implement different networking functionalities in the optical domain. A key component in WDM networks is the optical switch that provides the basic functionality of connecting input ports to output ports. Existing WDM switches make use of space switches and wavelength converters (WCs) to realize switching. However, this not only increases the size and the complexity of the switch but also bears heavily on the cost. In this paper, the authors propose a new class of photonic switch architectures called wavelength-exchanging cross connect (WEX) that provides several advantages over existing switches by enabling a single-step space switching and wavelength conversion and thus eliminating the need for a separate conversion stage. This greatly enhances the switch architecture by reducing its size and complexity. The new class of cross-connect architectures is based on the proposed concept of a wavelength-exchange optical crossbar (WOC). The WOC concept is realized using the simultaneous exchange between two optical signals. The proposed WEX architecture is highly scalable. To establish scalability, the authors present a systematic method of developing instances of the switch architectures of an arbitrary large size

Wavelength-exchanging cross connects (WEX)-a new class of photonic cross-connect architectures

IoT platforms play a central role in IoT architecture; as they enable the development of services and applications by end users. More than 300 IoT platforms were reported in the literature. IoT platforms vary in their capabilities and features. Accordingly, Selecting between the various platforms can be troublesome. This is particularly true given the fact that no benchmark or systematic evaluation criteria currently exist to evaluate and compare various platforms. To this end, this paper attempts to develop a performance evaluation for open source IoT platforms to reduce the complexity of the selection process. In particular, the paper evaluates the scalability (in terms of throughput and average response time) and stability (in terms of resource utilization and robustness) of the ThingsBoard and SiteWhere platforms. The two platforms are evaluated under heavy load of sensor data readings.

Performance Evaluation of Open Source IoT Platforms

Wireless Sensor Networks (WSNs) consist of a large number of nodes networked via wireless links. In many WSN settings, sensor nodes are deployed in an ad hoc manner. One important issue in this context is to detect the boundary of the deployed network to ensure that the sensor nodes cover the target area. In this paper, we propose a new algorithm that can be used to discover the boundary of a randomly deployed WSN. The algorithm does not require the sensor nodes to be equipped with positioning devices and is scalable for large number of nodes. Simulation experiments are developed to evaluate the performance of the proposed algorithms for different network topologies. The simulation results show that the algorithm detects the boundary nodes of the network with high accuracy.

Haitham S. Hamza

Papers

A Survey on Inter-Cell Interference Coordination Techniques in OFDMA-Based Cellular Networks

Coverage in mobile wireless sensor networks (M-WSN)

Wavelength-exchanging cross connects (WEX)-a new class of photonic cross-connect architectures

Performance Evaluation of Open Source IoT Platforms

An algorithm for boundary discovery in wireless sensor networks