A tutorial survey on vehicle-to-vehicle communications

Telecommunication Systems - The automotive industry is undergoing major transformation, with the emergence of vehicular networks, intelligent transportation systems, and autonomous cars over the...     

Dynamic pricing for load‐balancing in user‐centric joint call admission control of next‐generation wireless networks

Next‐generation wireless networks (NGWN) will be heterogeneous, comprising of a number of radio access technologies (RATs) co‐existing in the same geographical area. In NGWN, joint call admission control (JCAC) algorithms are required to select the most appropriate RAT for each incoming call. It is envisaged that these JCAC algorithms will be user‐centric (i.e. will consider users' preferences in making RAT selection decisions) in order to enhance user satisfaction. However, user‐centric JCAC algorithms can lead to highly unbalanced traffic load among the available RATs in NGWN because users act independently, and most of them may prefer to be connected through a particular RAT. Highly unbalanced traffic load in NGWN will result in high overall call blocking/dropping probability and poor radio result utilization. To address this problem, we propose dynamic pricing for balancing traffic load among available RATs in heterogeneous wireless networks where users' preferences are considered in making RAT selection decisions. By dynamically adjusting the service price in each of the available RATs, the proposed user‐centric JCAC scheme evens out the unbalanced traffic load caused by independent users' preferences. The JCAC scheme uses fuzzy multiple attribute decision‐making (MADM) technique to select the most appropriate RAT for each incoming call. We develop a Markov model to evaluate the overall call blocking/dropping probability and percentage load in each RAT in heterogeneous wireless networks. Performance of the proposed JCAC scheme is compared with that of a scheme that does not use dynamic pricing. Simulation results are given to show the effectiveness of the proposed JCAC scheme. Copyright © 2009 John Wiley & Sons, Ltd.     

ElectroBlocks: A blockchain‐based energy trading scheme for smart grid systems

Smart grid systems are widely used across the world for providing demand response management between users and service providers. In most of the energy distributions scenarios, the traditional grid systems use the centralized architecture, which results in large transmission losses and high overheads during power generation. Moreover, owing to the presence of intruders or attackers, there may be a mismatch between demand and supply between utility centers (suppliers) and end users. Thus, there is a need for an automated energy exchange to provide secure and reliable energy trading between users and suppliers. We found, from the existing literature, that blockchain can be an effective solution to handle the aforementioned issues. Motivated by these facts, we propose a blockchain‐based smart energy trading scheme, ElectroBlocks, which provides efficient mechanisms for secure energy exchanges between users and service providers. In ElectroBlocks, nodes in the network validate the transaction using two algorithms that are cost aware and store aware. The cost‐aware algorithm locates the nearest node that can supply the energy, whereas the store‐aware algorithm ensures that the energy requests go to the node with the lowest storage space. We evaluated the performance of the ElectroBlocks using performance metrics such as mining delay, network exchanges, and storage energy. The simulation results obtained demonstrate that ElectroBlocks maintains a secure trade‐off between users and service providers when using the proposed cost‐aware and store‐aware algorithms.     

Enabling gigabit network access to end users

To achieve innovative network architectures capable of delivering high-speed data transfers to end users, considerable efforts have been invested in minimizing or eliminating the bottlenecks that exist in high-speed network environments. These bottlenecks exist primarily at two levels, namely, network data transmission to the end system and data delivery within the end system to the user. For wired networks, improvements in fiber optic technologies have shifted the bottleneck from the underlying physical network to the end system. However, wireless networks still face obstacles at both levels to achieving high, end-to-end performance data delivery, particularly at gigabit per second rates. We first present current wireless communication technologies aimed at delivering gigabit per second transmission rates to end systems. We then investigate the bottleneck at the end system by exploring experimentally the performance benefits of a network interface architecture designed to enable high-performance, low-latency applications using minimal host resources. We compare the performance of our network interface architecture with the traditional one, using commodity PCs connected by gigabit per second local area networks running protocols such as TCP/IP and UDP/IP. We argue that such a network interface architecture can eliminate the bottlenecks prevalent in current end systems and, consequently, enables users to reap the full benefits of the high-speed networks available today.     

Enabling End-to-End QoS over Hybrid Wired-Wireless Networks

Providing end-to-end parameterized QoS is desirable for many network applications and has received a lot of attention in recent years. However, it remains a challenge, especially over hybrid networks involving both wired networks and wireless access segments (such as IEEE 802.11 Wireless Local Area Networks (WLANs)). The difficulty in achieving such QoS arises mainly because wireless segments often constitute “gaps" in terms of resource guarantee, due to the lack of efficient resource scheduling and management ability over shared wireless media, as well as the lack of an appropriate QoS signaling interface to seamlessly embed these wireless segments into an end-to-end QoS signaling system. In this paper, we consider the scenario where an IEEE 802.11 wireless node wishes to make an end-to-end resource reservation to a remote wired Internet node and vice versa. We propose Wireless Subnet Bandwidth Manager (Wireless SBM), an extension of SBM protocol to WLANs, to provide seamless end-to-end resource reservations. Wireless SBM utilizes the enhanced resource management ability provided by Hybrid Coordination Function (introduced in the upcoming IEEE 802.11e standard) to provide parameterized resource reservation and admission control.     

Quality of service models for heterogeneous networks: overview and challenges

The proliferation and convergence of different types of wired, wireless and mobile networks (such as WiMAX, Wireless Mesh Networks, WPANs, WLANs, etc) and cellular-based networks are crucial for the success of next-generation networks. Traditional wired/wireless networks can hardly meet the requirements of future integrated-service networks which are expected to carry multimedia traffic with various quality of service (QoS) requirements. Therefore, it is necessary to develop efficient global control mechanisms that can maintain QoS requirements to maximize network resources utilization, and minimize operational costs on all the types of wireless mobile networks. In this paper, we present an overview of QoS paradigms for heterogeneous networks and focus on those based on deterministic and probabilistic QoS.     

Distributed mobility management in named data networking

The information‐centric networking concept was proposed to fulfill the scalability and efficiency requirements of the content‐centric Internet in the future. Among the multiple information‐centric networking proposals, Named Data Networking (NDN) is one of the most important representatives. NDN uses a hierarchical name to identify the data after which the on‐path cache can be deployed to improve the efficiency of data retrieval. However, with the development of mobile Internet, how to extend NDN in the mobile environment to enable efficient and scalable mobility management remains a challenge. We propose a distributed mobility management scheme for both the mobile receiver and the mobile publisher in NDN. Our proposed approach is based on the basic NDN naming and routing principles to select the branching node of the previous and new access locations of the mobile terminal after which the on‐path routing states are dynamically adjusted accordingly. Then we propose a novel analytical model to analyze the performance of the proposed scheme. The results demonstrate that the proposed scheme inherits the scalability and efficiency of NDN in the mobile Internet. Copyright © 2015 John Wiley & Sons, Ltd.