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Fuel utilization efficiency and cost reduction are two major goals in designing in-vehicle networks. Aiming to address these two issues, we investigate in-vehicle networking protocols from both wired and wireless perspectives by first presenting representative solutions in each area, then identifying the challenges to current solutions, and finally advocating the use of the automotive Ethernet. Also, we propose a priority-based scheduler for the automotive Ethernet. Our preliminary experiments show that the proposed scheduler is effective and flexible, and thus is applicable to next-generation in-vehicle networks. We hope that further studies in this area can be inspired by our work and will be forthcoming in years to come. [ABSTRACT FROM AUTHOR]

In this article, we propose a novel networking paradigm called Small-world SSDNet, servicing applications such as public safety, proximity based services, and fog computing based on device-todevice multi-hop wireless communications. The "small-world" feature is determined by the service area, whose size is usually within a community level, and the well known small-world properties existing in SSDNets; the "super-dense" feature comes from the fact that the increased direct communication range and the popularity of 5G and IoT devices jointly result in a large number of devices within a single-hop communication range. This article first formally defines SSDNet. Then the challenges and the opportunities brought by the design and the implementation of the SSDNet protocols and applications are addressed. Finally, the broader discussions on issues relevant to modeling, engineering, and dissemination are provided. [ABSTRACT FROM AUTHOR]

RFID is one of the most important automatic identification techniques in the future IoT world. Compared with the other techniques, RFID has various advantages such as no requirement of line of sight, the capability of wireless communication, low cost, small size, and so on. This article discusses two types of anomaly tags, i.e., missing tags and unknown tags, which usually appear due to theft or product misplacement. Generally, there are two categories of anomaly tag pinpointing protocols: boolean detection, which aims at probabilistically determining whether there exist anomaly tags or not; and exact identification, which aims at identifying all anomaly tag IDs. This article first conducts a comprehensive survey of the existing anomaly tag pinpointing protocols, particularly emphasizing their evolution road. After that, we also conduct a taxonomy of the existing protocols and summarize their pros and cons. Finally, we discuss some technical challenges and problems that have not been covered yet, and point out the potential opportunities in RFID research and applications. [ABSTRACT FROM AUTHOR]

Driven by the increasing demand on marine exploration, UWANs are confronted with the rigorous challenge of improving network throughput. To deal with this challenge, this article proposes to apply the IBFD technique to UWANs. The IBFD technique can potentially double link capacity by simultaneously transmitting and receiving on the same frequency band, which has been recently demonstrated to be feasible for wireless communications. In this article, novel MAC protocols are specifically proposed for the acoustic IBFD network to overcome the inherent issues in underwater acoustic communications, such as long packet delay, large node collision probability, and high power consumption. Numerical results verify that our proposals can effectively mitigate these effects and improve the overall performance of the UWANs. [ABSTRACT FROM AUTHOR]

Geographic routing has been considered as an attractive approach for wireless mobile ad hoc and sensor networks due to its effectiveness and scalability. Over the past few decades, numerous geographic routing protocols have been proposed extensively in 2D space. However, these protocols are no longer valid if ad hoc or sensor networks are distributed in 3D environments, such as space, atmosphere, and ocean. Because of the surprisingly difficulty of designing geographic routing protocols for 3D networks compared to 2D networks, only a few prior studies have focused on 3D geographic routing specifically designed for ad hoc and sensor networks. In this article, we first illustrate the principles of 3D geographic routing, and categorize current research work based on different criteria. Then we compare the 3DGR protocols under study through comprehensive analysis. Finally, we point out the open issues and opportunities for further research. [ABSTRACT FROM AUTHOR]

Although widely used, TCP has many limitations in meeting the throughput and latency requirements of applications in wireless networks, high-speed data center networks, and heterogeneous multi-path networks. Instead of relying purely on retransmission upon packet loss, coding has potential to improve the performance of TCP by ensuring better transmission reliability. Coding has been verified to work well at the link layer but has not been fully studied at the transport layer. There are many advantages but also challenges in exploiting coding at the transport layer. In this article, we focus on how to leverage end-to-end coding in TCP. We reveal the problems TCP faces and the opportunities coding can bring to improve TCP performance. We further analyze the challenges faced when applying the coding techniques to TCP and present the current applications of coding in TCP. [ABSTRACT FROM AUTHOR]

Telecommunications service providers are exploring the use of standard high-volume servers to reduce total cost of ownership while at the same time increasing flexibility, service velocity, and scalability of network functions. This article characterizes performance of general-purpose processors ? specifically x86 architecture processors ? for signaling and bearer processing representative of a wireless carrier?s call model for a Long Term Evolution Evolved Packet Core. A radio access network emulator was used to stimulate an Evolved Packet Core software stack running on an x86 server. The goal was to prove that standard high-volume servers can execute EPC functions per representative market call models, and that workloads can scale across bearer and control plane at line rate without acceleration technologies. A call model was developed to quantify the performance on Intel? Xeon? Processor based servers using an LTE traffic simulator and a commercial EPC software stack. The traffic models represent bidirectional real-world network traffic during different times of the day. The results were that the test EPC processed control and user plane traffic with 50,000 subscribers with a total payload of 10 Gb/s downlink + 4.8 Gb/s uplink traffic using five cores for the data plane and eight cores for the rest of the system; and the user plane throughput scaled in a single blade environment to 20 Gb/s per socket or 40 Gb/s for a dual socket blade. [ABSTRACT FROM PUBLISHER]

The article presents the recent developments on Internet Protocol (IP) authentication that can reduce the re-authentication delay. These newly developed protocols are the IEEE 802.11 r and the Extensible Authentication Protocol (EAP) Re-authentication Protocol (ERP) for handover keying (HOKEY). These two protocols utilize the key hierarchies to avoid full authentication. The control and provisioning of wireless access points (CAPWAP) architecture was introduced to illustrate different optimizations.

The article presents a study which examines the localization capability of ultra-wide band to provide a variety of location-based services (LBSs) in various assets of data centers and Information Technology environment. Discussions on localization technologies, wireless universal serial bus localization protocol, estimation method for location, and the accuracy of the localization protocol are provided. It discusses the necessity of enabling LBSs in data centers through virtualization and the services that can manipulate LBSs which include coarse grain localization, medium grain localization, and the dynamic migration of the virtual machines. It proposes a management framework for LBS using three layers for the maintenance of power/thermal equilibrium.

The article discusses the study which advocates the design of a new network layer that can support multihop communications efficiently in Worldwide Interoperability for Microwave Access (WiMAX) networks and that can fully exploit the features of the WiMAX standards. The study identifies services that are important for broadband wireless network providers and investigates the requirements for different services. It also illustrates how to design WiMAX networks by considering issues of efficiency, security, and reliability.

The article discusses the study that focuses on wireless mesh networking and the insights into the related standardization efforts in IEEE 802. The study illustrates the draft wireless local area network (WLAN) mesh standard IEEE 802.11s and identifies challenges for medium access control in multihop communication. Derived from the study's proposal to 802.11s, its draft incorporates an optional medium access scheme that circumvents a performance gap. It also compares the performance of both solutions and provide an outlook for future 802 wireless systems that will be more reliable.

The article discusses the need for access point power saving in solar powered wireless local area network (WLAN) mesh networks. These WLAN mesh networks have been used to deploy wireless fidelity (Wi-Fi) coverage in a wide variety of outdoor applications. It is noted that the conventional WLAN mesh nodes for the networks are required to be operated using continuous electrical power connections, but the said requirement is often expensive especially when the network includes expansive outdoor wireless coverage areas. An alternative has been discussed which is to operate some of the WLAN mesh nodes using an energy sustainable source, such as solar or wind power.

The article offers information on the proposed quality of service differentiation scheme for the Institute of Electrical and Electronics Engineers (IEEE) 802.16 wireless mesh networks. According to the article, WMN is becoming an important architecture of future generations of wireless communications systems wherein the quality of service provisioning provides an essential role in optimizing its performance. It provides a detailed discussion on the system model, frame structure, different scheduling schemes and collocated topology. It also discusses the different relevant issues and potential performances associated with the approach.

The article discusses the concept of cooperative game theory in the optimization of medium access control (MAC) protocol of wireless mesh networks (WMN) communication infrastructure performance. Accordingly, the game theory estimates the available nodes which will be adjusted to its equilibrium strategy to be repeated for several times, and for an effective analysis, a carrier sense multiple access/collision avoidance (CSMA/CA) protocol was integrated which allows mode switching. The author concludes that a CSMA/CA based game theory provides an effective simulation result that ameliorates throughput and decreases delay, jitter and packet loss rate.

The article focuses on the alternative routing paradigm for the optimization of large multihop wireless mesh networks (WMN). According to the author, routing protocols of wireless mesh networks must take advantage of the specific topology and traffic pattern with scalability and gateways for an advanced functionality. It also discusses the concept of HEAT, field-based unicast temperature routing protocol that provides robust routes with mobile nodes in a faster and quicker speed that is suitable for use in large and dense networks. It also presents a comparison on the performance of HEAT with ad hoc on-demand distance vector (AODV) and optimized link state routing (OLSR) applications

The article presents a survey of several quality of service (QoS)-aware unicast routing protocols for mobile ad hoc network (MANETs). It compared the routing protocols in terms of their support for node mobility, their routing overhead, their requirements for extra node hardware, and their support for scaling of the network. The authors also pointed out the open issues that must be addressed in QoS-aware routing in terms of bandwidth/delay estimation, route discovery, resource reservation, and route maintenance.

The article discusses the proposed generic analytical model for medium access control (MAC) protocol in wireless broadband access networks. The model is based on a hierarchical three-level renewal process mechanism which directs to some significant MAC protocol performance metrics. The model is a very general analytical framework that can be also applied to protocols with various types of backoff policies and widely used in several wireless broadband access networks. It has been tested to the recent work of the performance analysis of the prioritized channel access MAC protocol in multiband orthogonal-frequency-division-multiplexing-based ultra wideband.

The article addresses the need for over-the-air support for software updates in Wireless Sensor Networks (WSN). It consolidates by determining an integrated set of necessary WSN software update criteria and presents a novel model for WSN software update systems. WSNs are expected to be deployed for a long period of time and the nodes are likely to need software updates during their lifetime, both for bug fixes and to support new requirements. However, in many cases the nodes will be inaccessible or too numerous to be physically accessed which needs a new software update model. It describes the problems associated with the software update problem in WSNs and presents the derived criteria for software updating.

The article discusses the outstanding aspects of the wireless channel and the challenges and opportunities they introduce for streaming media. Streaming technology has a number of fundamental characteristics that distinguished it from generic data for which most wireless protocols are designed. This would mean that solutions made for media distribution in wired contexts do not directly transform into an appropriate wireless solutions. A number of examples are discuss such as how channel, source and application-dependent concepts such as multiuser diversity, opportunistic communications, loss tolerance and differing application-dependent delay constraints can be overworked to introduce new and useful constructs for streaming media over wireless.

In the article the authors describe different types of sensor network applications and discuss existing techniques for managing these types of networks. The authors also overview a variety of related middleware and argue that no existing approach provides all the management tools required by sensor network applications. To meet this need, they have developed a new middleware called MiLAN. MiLAN allows applications to specify a policy for managing the network and sensors, but the actual implementation of this policy is effected within MiLAN. The authors describe MiLAN and present its effectiveness through the design of a sensor-based personal health monitor.

Discusses issues of coexistence between Bluetooth and Wi-Fi(802.11b) wireless systems. Explanation of basic interference mechanisms and quantification of their impact; Simulation of the physical layer and media access control of both wireless systems; Techniques with the potential to improve the performance of collocated Bluetooth and Wi-Fi systems.

Cognitive functions in wireless network nodes are beneficial for leveraging intricate trade-offs among energy efficiency, performance and practicality. There are two fundamental but entangled aspects of cognitive radios in the green communications context: leveraging CRs for energy efficiency and operation of CRs with energy efficiency. In practice, these two objectives overlap since the improvement of energy efficiency with CRs require efficient CRs, whereas efficient wireless communications require cognitive abilities at different network components and protocols. However, there are intrinsic challenges such as hardware complexity, algorithmic problems, and design trade-offs. In this article we present and discuss these issues to highlight the case of CRs for green wireless communication systems. Additionally, some fundamental trade-offs that emerge from these challenges and their impact on greening communications via cognitive functions are outlined. [ABSTRACT FROM PUBLISHER]