Machine-to-Machine (M2M) communication plays a pivotal role in the evolution of Internet of Things (IoT). Cellular networks are considered to be a key enabler for M2M communications, which are originally designed mainly for Human-to-Human (H2H) communications. The introduction of M2M users will cause a series of problems to traditional H2H users, i.e., interference between various traffic. Resource allocation is an effective solution to these problems. In this paper, we consider a shared resource block (RB) and power allocation in an H2H/M2M coexistence scenario, where M2M users are subdivided into delay-tolerant and delay-sensitive types. We first model the RB-power allocation problem as maximization of capacity under Quality-of-Service (QoS) constraints of different types of traffic. Then, a learning framework is introduced, wherein a complex agent is built from simpler subagents, which provides the basis for distributed deployment scheme. Further, we proposed distributed Q-learning based autonomous RB-power allocation algorithm (DQ-ARPA), which enables the machine type network gateways (MTCG) as agents to learn the wireless environment and choose the RB-power autonomously to maximize M2M pairs' capacity while ensuring the QoS requirements of critical services. Simulation results indicates that with an appropriate reward design, our proposed scheme succeeds in reducing the impact of delay-tolerant machine type users on critical services in terms of SINR thresholds and outage ratios.

The Machine-to-Machine (M2M) service network platform accommodates M2M communications traffic efficiently by using tree-structured networks and the computation resources deployed on network nodes. In the M2M service network platform, program files required for controlling devices are placed on network nodes, which have different amounts of computation resources according to their position in the hierarchy. The program files must be dynamically repositioned in response to service quality requests from each device, such as computation power, link bandwidth, and latency. This paper proposes a Program File Placement (PFP) method for the M2M service network platform. First, the PFP problem is formulated in the Mixed-Integer Linear Programming (MILP) approach. We prove that the decision version of the PFP problem is NP-complete. Next, we present heuristic algorithms that attain sub-optimal but attractive solutions. Evaluations show that the heuristic algorithm based on the number of devices that share a program file reduces the total number of placed program files compared to the algorithm that moves program files based on their position.

The 5G mobile network environment has been studied and developed, and the concept of a vEPC (Virtualized Evolved Packet Core) has been introduced as a framework for Network Functions Virtualization (NFV). Machine-to-Machine (M2M) communications in 5G networks require much faster response than are possible in 4G networks. However, if both the control plane (C-plane) and the data plane (D-plane) functions of the EPC are migrated into a single vEPC server, M2M devices and other user equipments (UEs) share the same resources. To accommodate delay-sensitive M2M sessions in vEPC networks, not only signaling performance on the C-plane but also packet processing performance on the D-plane must be optimized. In this paper, we propose a method for optimizing resource assignment of C-plane and D-plane Virtualized Network Functions (VNFs) in a vEPC server, called the vEPC-ORA method. We distinguish the communications of M2M devices and smartphones and model the vEPC server by using queueing theory. Numerical analysis of optimal resource assignment shows that our proposed method minimizes the blocking rates of M2M sessions and smartphone sessions. We also confirmed that the mean packet processing time is kept within the allowable delay for each communication type, as long as the vEPC server has enough VM resources. Moreover, we study a resource granularity effect on the optimal resource assignment. Numerical analysis under a fixed number of hardware resources of MME and S/P-GW is done for various resource granularities of the vEPC server. The evaluation results of numerical analyses showed that the vEPC-ORA method derives the optimal resource assignment in practical calculation times.

Image sensor communication (ISC), a type of visible light communication, is an emerging wireless communication technology that uses LEDs to transmit a signal and uses an image sensor in a camera to receive the signal. This paper discusses the present status of and future trends in ISC by describing the essential characteristics and features of ISC. Moreover, we overview the products and expected future applications of ISC.

Information-centric networking (ICN) has been investigated as a new communication model that is optimal for data registration and retrieval. A promising application of ICN is mobile machine-to-machine (M2M) communication in which data are registered by M2M terminals, such as vehicles, and retrieved by other M2M terminals. One of the most difficult challenges with ICN is achieving data mobility in which the data are registered by moving terminals and the location of the data changes constantly. To gain access to moving data, the data retrieval messages must access the routing information, which results in a high volume of message transaction loads of high-tier nodes such as the name resolution nodes. We previously proposed a scheme called data-centric network (DCN), which mitigates this problem by allocating multiple intermediate nodes that act as route aggregation points and by establishing optimized routes. In this paper, we compare the transaction load of DCN with those of conventional ICN schemes using theoretical evaluation based on probability calculation. We also compare the amount of route information and transaction loads using a simulator against binary tree and ISP backbone topologies. From these evaluations, we clarify the characteristics of each ICN scheme in different terminal distribution and communication patterns and show that DCN reduces the transaction loads of high-tier nodes when the terminals are communicating locally.

To reduce the server load and communication costs of machine-to-machine (M2M) systems, sensor data are aggregated in M2M gateways. Aggregation logic is typically programmed in the C language and embedded into the firmware. However, developing aggregation programs is difficult for M2M service providers because it requires gateway-specific knowledge and consideration of resource issues, especially RAM usage. In addition, modification of aggregation logic requires the application of firmware updates, which are risky. We propose a rule-based sensor data aggregation system, called the complex sensor data aggregator (CSDA), for M2M gateways. The functions comprising the data aggregation process are subdivided into the categories of filtering, statistical calculation, and concatenation. The proposed CSDA supports this aggregation process in three steps: the input, periodic data processing, and output steps. The behaviors of these steps are configured by an XML-based rule. The rule is stored in the data area of flash ROM and is updatable through the Internet without the need for a firmware update. In addition, in order to keep within the memory limit specified by the M2M gateway's manufacturer, the number of threads and the size of the working memory are static after startup, and the size of the working memory can be adjusted by configuring the sampling setting of a buffer for sensor data input. The proposed system is evaluated in an M2M gateway experimental environment. Results show that developing CSDA configurations is much easier than using C because the configuration decreases by 10%. In addition, the performance evaluation demonstrates the proposed system's ability to operate on M2M gateways.

In the near future, many sensors and terminals will be connected to the public network to provide various convenient IoT/M2M services. In order to connect many sensors to the network efficiently, wireless communication systems in the 920MHz band are seen as attractive solutions. We are focusing on the 920MHz band to research and develop high-capacity protocols that can accommodate many terminals, and low power consumption technologies for battery-driven terminals. In this paper, we describe the following three concrete wireless systems that use our proposals. (1) A physical distribution pallet management system that can handle thousands of pallet-embedded sensors and a wireless module with a battery lifetime of about ten years. (2) Water leakage monitoring system for underground pipes by using sensors and a wireless module in each valve box. (3) A wide-area and high-capacity radio relay system for smart metering services like the reading of gas meters. The radio relay system can accommodate various sensors and terminals and has large potential for providing various IoT/M2M services in conjunction with smart metering services.

In this paper, the average symbol error probability (SEP) performance of decode-and-forward (DF) relaying mobile-to-mobile (M2M) systems with transmit antenna selection (TAS) over N-Nakagami fading channels is investigated. The moment generating function (MGF) method is used to derive exact SEP expressions, and the analysis is verified via simulation. The optimal power allocation problem is investigated. Performance results are presented which show that the fading coefficient, number of cascaded components, relative geometrical gain, number of antennas, and power allocation parameter have a significant effect on the SEP.

Cyber-attacks and cybersecurity used to be the issues for those who use Internet and computers. The issues, however, are expanding to anyone who does not even use them directly. The society is gradually and heavily depending on networks and computers. They are not closed within a cyberspace anymore and having interaction with our real world with sensors and actuators. Such systems are known as CPS (Cyber Physical Systems), IoT/E (Internet of Things/Everything), Industry 4.0, Industrial Internet, M2M, etc. No matter what they are called, exploitation of any of these systems may cause a serious influence to our real life and appropriate countermeasures must be taken to mitigate the risks. In this paper, cybersecurity in ICS (Industrial Control Systems) is reviewed as a leading example of cyber physical security for critical infrastructures. Then as a future aspect of it, IoT security for consumers is explained.

3GPP Long Term Evolution (LTE) is one of the most advanced technologies in the wireless and mobility field because it provides high speed data and sophisticated applications. LTE was originally deployed by service providers on various platforms using separate dedicated hardware in Access radio layer and the Evolved Packet Core network layer (EPC), thereby limiting the system's flexibility and capacity provisioning. Thus, the concept of virtualization was introduced in the EPC hardware to solve the dedicated hardware platform limitations. It was also introduced in the IP Multimedia Subsystem (IMS) and Machine to Machine applications (M2M) for the same reason. This paper provides a simulation model of a virtualized EPC and virtualized M2M transport application server connected via an external IP network, which has significant importance in the future of mobile networks. This model studies the virtualized server connectivity problem, where two separate virtual machines communicate via the existing external legacy IP network. The simulation results show moderate performance, indicating that the selection of IP technology is much more critical than before. The paper also models MPLS technology as a replacement for the external IP routing mechanism to provide traffic engineering and achieve more efficient network performance. Furthermore, to provide a real network environment, Poisson Pareto Burst Process (PPBP) traffic source is carried over the UDP transport layer which matches the statistical properties of real-life M2M traffic. Furthermore, the paper proves End-to-End interoperability of LTE and MPLS running GTP and MPLS Label Forwarding information Base (LFIB) and MPLS traffic engineering respectively. Finally, it looks at the simulation of several scenarios using Network Simulator 3 (NS-3) to evaluate the performance improvement over the traditional LTE IP architecture under M2M traffic load.

In this paper, we introduce a distributed power allocation strategy for random access, that has the capabilities of multipacket reception (MPR) and successive interference cancellation (SIC). The proposed random access scheme is suitable for machine-to-machine (M2M) communication application in fifth-generation (5G) cellular networks. A previous study optimized the probability distribution for discrete transmission power levels, with implicit limitations on the successful decoding of at most two packets from a single collision. We formulate the optimization problem for the general case, where a base station can decode multiple packets from a single collision, and this depends only on the signal-to-interference-plus-noise ratio (SINR). We also propose a feasible suboptimal iterative per-level optimization process; we do this by introducing relationships among the different discrete power levels. Compared with the conventional power allocation scheme with MPR and SIC, our method significantly improves the system throughput; this is confirmed by computer simulations.

Wireless communications for the control of industrial equipments need to send a large amount of short packets frequently and to improve frame efficiency. The OFDM frame of wireless local area networks has short preambles that are used for timing synchronization and coarse frequency offset estimation. As the short preambles are repeated in a time domain, they occupies subcarriers intermittently. Therefore, in this paper, a new frame format with OFDM modulation in which data symbols are orthogonally multiplexed with the preamble symbols in the frequency domain is proposed. Two preamble sequences that are based on an IEEE802.11g short preamble sequence and a Zadoff-Chu sequence are examined. The ratio of transmission powers between the pilot subcarrier and the data subcarrier is also varied. The timing synchronization probability with those sequences has been evaluated on different channel models. It is shown through the experiment that the synchronization performance is almost the same as that without data multiplexing at Es/N0 of more than 8dB.

This paper proposes a new small multiband printed antenna for wireless telecommunications modules that can realize Machine-to-Machine applications. We reconfigure our previous antenna to cover the 700MHz, 800MHz, and 900MHz bands, and add two new elements (second strips) to cover the 2GHz band. The new antenna achieves operation in quad-bands: 700MHz, 800MHz, 900MHz, and 2GHz. Frequency characteristics are analyzed using electromagnetic-simulation software based on the method of moments, and the validity of the numerical results is shown based on measured Voltage Standing Wave Ratio (VSWR) characteristics and the radiation patterns of a prototype antenna. The proposed antenna is compact with a VSWR bandwidth (≤2) of 27.5% in bands including 700MHz, 800MHz, and 900MHz, and a VSWR bandwidth (≤2) of 10.6% in the band including 2GHz. We clarify that the operating mechanism in the 2GHz band is equivalent to that of a one wavelength folded offset fed dipole antenna comprising a monopole element and second strips, and that the operating frequency in the 2GHz band can be determined by the path length from the tip of the monopole element to the tip of the second strip via a feeding point.

As a promising wireless access standard for machine-to-machine (M2M) networks, the IEEE 802.11 task group ah has been discussing a new standard which is based on the wireless local area network (WLAN) standard. This new standard will support an enormous number of stations (STAs) such as 6,000 STAs. To mitigate degradation of the throughput and delay performance in WLANs that employ a carrier sense multiple access with collision avoidance (CSMA/CA) protocol, this paper proposes a virtual grouping method which exploits the random arbitration interframe space number scheme. This method complies with the CSMA/CA protocol, which employs distributed medium access control. Moreover, power saving is another important issue for M2M networks, where most STAs are operated by primary or secondary batteries. This paper proposes a new power saving method for the IEEE 802.11ah based M2M network employing the proposed virtual grouping method. With the proposed virtual grouping and power saving methods, the STAs can save their power by as much as 90% and maintain good throughput and delay performance.

Machine-to-Machine (M2M) communication is expected to grow in networks of the future, where massive numbers of low cost, low function M2M terminals communicate in many-to-many manner in an extremely mobile and dynamic environment. We propose a network architecture called Data-centric Network (DCN) where communication is done using a data identifier (ID) and the dynamic data registered by mobile terminals can be retrieved by specifying the data ID. DCN mitigates the problems of prior arts, which are large size of routing table and transaction load of name resolution service. DCN introduces concept of route attraction and aggregation in which the related routes are attracted to an aggregation point and aggregated to reduce routing table size, and route optimization in which optimized routes are established routes to reduce access transaction load to the aggregation points. These allow the proposed architecture to deal with ever increasing number of data and terminals with frequent mobility and changes in data.