WHOMoVeS: An optimized broadband sensor network for military vehicle tracking

With the advance of sensing technologies and their applications, advanced sensor networks are gaining increasing interest. For certain sensitive applications, heterogeneous sensors can be deployed in the monitored space to ensure scalability, high-speed communication, and long network lifetime. Hybrid sensor networks have capabilities to combine the use of both resource-rich and resource-impoverished sensor nodes. This paper proposes a heterogeneous broadband sensor network architecture for military vehicle tracking. Powerful sensor devices with good bandwidth and energy capabilities are used as a communication backbone while energy sensors are used to track moving targets. Copyright © 2007 John Wiley & Sons, Ltd.     

Twelve random access strategies for the fiber optic networks

Twelve random-access strategies that do not constrain the distance or transmission rate of a network, and can use the capabilities of fiber-optic components, are described and compared. The twelve strategies consist of three protocols, each of which can use two timing arrangements and two network-access devices. The three protocols are the standard ALOHA protocol, LCSMA, and LCSMA/CD. The last two protocols operate on linear-unidirectional networks and use local information at the transmitter to increase the throughput of the system. The networks considered have a common point that all transmitted signals pass through before being received. This makes two timing arrangements possible; a slotted system or an unslotted system. The taps on the network can be either passive or active     

Mobile device‐centric access point monitoring scheme for handover decision triggering in heterogeneous networks

Because of the low throughput and the high packet error rate in wireless communications, the network traffic often converges at access points (APs), which take a role of connecting wired and wireless communication interfaces, and APs are usually bottleneck points in wireless networks. In heterogeneous networks, various networks are around mobile devices. Furthermore, today's mobile devices have various wireless network capabilities. Thus, mobile devices should be able to understand network situations autonomously and use a wide range of network options in heterogeneous networks. However, since current mobile devices cannot know the connected AP's network condition, they continue to use the AP, which provides poor‐quality networks even though there are other available APs and networks nearby. To resolve the aforementioned problems, we propose MAPS , the low‐power AP monitoring scheme for handover decision triggering in heterogeneous networks. Using MAPS , a mobile device can trigger a handover decision properly through predicting the connected AP's network condition accurately without any cooperation from other devices. Furthermore, MAPS does not require any modification on existing network systems, and the mobile device can use MAPS with simple application installation. Through diverse simulations, actual experiments, and power consumption analysis, we validate that MAPS can detect the busy AP effectively and is suitable for mobile devices because of low power consumption.     

Network Partitioning Recovery Mechanisms in WSANs: a Survey

Wireless sensor and actor networks (WSANs) are more promising and most addressing research field in the area of wireless sensor networks in recent scenario. It composed of possibly a large number of tiny, autonomous sensor devices and resources rich actor nodes equipped with wireless communication and computation capabilities. Actors collect sensors’ information and respond collaboratively to achieve an application specific mission. Since actors have to coordinate their operation, a strongly connected inter-actor network would be required at all the time in the network. Actor nodes may fail for many reasons (i.e. due of battery exhaustion or hardware failure due to hash environment etc.) and failures may convert connected network into disjoint networks. This can hinder sometimes not only the performance of network but also degrade the usefulness and effectiveness of the network. Thus, having a partitioning detection and connectivity restoration procedure at the time of failure occurs in the network is crucial for WSANs. In this paper, we review the present network partitioning recovery approaches and provide an overall view of this study by summarizing previous achievements.     

A negotiation-based networking methodology to enable cooperation across heterogeneous co-located networks

In a future internet of things, an increasing number of every-day objects becomes interconnected with each other. Current network solutions are not designed to connect a large number of co-located devices with different characteristics and network requirements. To cope with increasingly large and heterogeneous networks, this paper presents an ‘incentive driven’ networking approach that optimizes the network performance by taking into account the network goals (‘incentives’) of all individual devices. Incentive driven networking consists of the following steps. First, devices dynamically search for co-located devices with similar network preferences and hardware and/or software capabilities. Next, if such devices are found, communities consisting of interconnected objects with similar network expectations are formed on an ad hoc basis. Due to the similarities between the involved devices, it is easier to optimize the network performance of each individual community. Finally, different communities can cooperate with each other by activating and sharing (software or hardware) network resources. The paper describes which (future) research is needed to realize this vision and illustrates the concepts with a number of simple algorithms. Through an experimental proof-of-concept implementation with two networks of resource-constrained embedded devices, it is shown that even these simple algorithms already result in improved network performance. Finally, the paper describes a large number of example use cases that can potentially benefit from our innovative networking methodology.     

A Cross-Layer Admission Control Framework for Wireless Ad-Hoc Networks using Multiple Antennas

Unlike single omnidirectional antennas, multiple antennas offer wireless ad-hoc networks potential increases in their achievable throughput and capacity. Due to recent advances in antenna technology, it is now affordable to build wireless devices with more than one antenna. As a result, multiple antennas are expected to be an essential part of next-generation wireless networks to support the rapidly emerging multimedia applications characterized by their high and diverse QoS needs. This paper develops an admission control framework that exploits the benefits of multiple antennas to better support applications with QoS requirements in wireless ad-hoc networks. The developed theory provides wireless ad-hoc networks with flow-level admission control capabilities while accounting for cross-layer effects between the PHY and the MAC layers. Based on the developed theory, we propose a mechanism that multiple antenna equipped nodes can use to control flows' admissibility into the network. Through simulation studies, we show that the proposed mechanism results in high flow acceptance rates and high network throughput utilization.     

Will video caching remain energy efficient in future core optical networks?

Optical networks are expected to cater for the future Internet due to the high speed and capacity that they offer. Caching in the core network has proven to reduce power usage for various video services in current optical networks. This paper investigates whether video caching will still remain power efficient in future optical networks. The study compares the power consumption of caching in a current IP over WDM core network to a future network. The study considers a number of features to exemplify future networks. Future optical networks are considered where: (1) network devices consume less power, (2) network devices have sleep-mode capabilities, (3) IP over WDM implements lightpath bypass, and (4) the demand for video content significantly increases and high definition video dominates. Results show that video caching in future optical networks saves up to 42% of power consumption even when the power consumption of transport reduces. These results suggest that video caching is expected to remain a green option in video services in the future Internet.     

Exploring the intra-frame energy conservation capabilities of the horizontal simple packing algorithm in IEEE 802.16e networks: an analytical approach

The power saving capabilities of the mobile devices in broadband wireless networks constitute a challenging research topic that has attracted the attention of researchers recently, while it needs to be addressed at multiple layers. This work provides a novel analysis of the intra-frame energy conservation potentials of the IEEE 802.16e network. Specifically, the power saving capabilities of the worldwide interoperability for microwave access downlink sub-frame are thoroughly studied, employing the well-known simple packing algorithm as the mapping technique of the data requests. The accurate mathematical model, cross-validated via simulation, reveals the significant ability to conserve energy in this intra-frame fashion under different scenarios. To the best of our knowledge, this is the first work providing intra-frame power-saving potentials of IEEE 802.16 networks. Additionally, this is the first study following an analytic approach.     

Networks and systems for BT in the 21st century

This paper provides an overview of BT’s 21st century network architecture. Analysis shows that this will deliver an improved customer experience, faster service provision and a significant overall cost reduction on today’s base. These aims can only be achieved by a ground-breaking approach which moves from multiple networks each providing one service to a true multiservice network where the services are delivered by combining reusable capabilities. The architecture is therefore based on network, intelligence and operational support systems built from reusable components and an application layer that can expose these capabilities through open interfaces.     

Position and orientation in ad hoc networks

Position and orientation information of individual nodes in ad hoc networks is useful for both service and application implementation. Services that can be enabled by availability of position include routing and querying. At application level, position is required in order to label the reported data in a sensor network, whereas position and orientation enable tracking.Nodes in an ad hoc network may have local capabilities such as the possibility of measuring ranges to neighbors, angle of arrival (AOA), or global capabilities, such as GPS and digital compasses. This article investigates the possibility of using local capabilities to export global capabilities using a distributed, localized, hop by hop method. We show how position and orientation of all the nodes in a connected ad hoc network can be determined with a small fraction of landmarks that can position/orient themselves, given that all nodes have some combination of local capabilities.     

The Phoenix framework: a practical architecture for programmablenetworks

Programmable networks allow third parties to dynamically reprogram switches and routers in order to extend their functionality. This approach facilitates new capabilities such as dynamic reallocation of resources, automated healing from malfunctions and failures, customized information processing, and easier service creation. These capabilities enable rapid customization of the network by providing mechanisms to adapt to new applications such as multimedia, multicast, intrusion detection, and intranet firewalls. We describe Intel's framework for programmable networks, known as Phoenix. The objective of the Phoenix framework is to make it easier to deploy new network services that leverage the emerging trend toward use of reprogrammable network processors. To accomplish this goal the Phoenix framework defines an extensible mobile agent system and a set of device functionality abstractions for utilizing and extending network capabilities. We also discuss how the open interfaces provided by the Phoenix framework can be utilized to deploy new network services     

Robust Rate Control for Heterogeneous Network Access in Multihomed Environments

We investigate a novel robust flow control framework for heterogeneous network access by devices with multi-homing capabilities. Towards this end, we develop an H-infinity-optimal control formulation for allocating rates to devices on multiple access networks with heterogeneous time-varying characteristics. H-infinity analysis and design allow for the coupling between different devices to be relaxed by treating the dynamics for each device as independent of the others. Thus, the distributed end-to-end rate control scheme proposed in this work relies on minimum information and achieves fair and robust rate allocation for the devices. An efficient utilization of the access networks is established through an equilibrium analysis in the static case. We perform measurement tests to collect traces of the available bandwidth on various WLANs and Ethernet. Through simulations, our approach is compared with AIMD and LQG schemes. In addition, the efficiency, fairness, and robustness of the H-infinity-optimal rate controller developed are demonstrated via simulations using the measured real world network characteristics. Its favorable characteristics and general nature indicate applicability of this framework to a variety of networked systems for flow control.     

Design and implementation analysis of a public key infrastructure‐enabled security framework for ZigBee sensor networks

ZigBee is a wireless network technology suitable for applications requiring lower bandwidth, low energy consumption and small packet size. Security has been one of the challenges in ZigBee networks. Public Key Infrastructure (PKI) provides a binding of entities with public keys through a Certifying Authority (CA). Public key cryptography using public–private key pairs can be used for ensuring secure transmission in a network. But large size of public and private keys and memory limitations in ZigBee devices pose a problem for using PKI to secure communication in ZigBee networks. In this paper, we propose a PKI enabled secure communication schema for ZigBee networks. Limited memory and power constraints of end devices restrict them from storing public keys of all other devices in the network. Large keys cannot be communicated due to limited power of the nodes and small transmission packet size. The proposed schema addresses these limitations. We propose two algorithms for sending and receiving the messages. The protocols for intercommunication between the network entities are also presented. Minor changes have been introduced in the capabilities of devices used in the ZigBee networks to suit our proposed scheme. Network adaptations depending on different scenarios are discussed. The approach adopted in this paper is to alter the communication flow so as to necessitate minimum memory and computational requirements at the resource starved end points. In the proposed PKI implementation, end devices store the public keys of only the coordinator which in turn holds public keys of all devices in the network. All communication in our scheme is through the coordinator, which in the event of failure is re‐elected through an election mechanism. The performance of the proposed scheme was evaluated using a protocol analyzer in home automation and messenger applications. Results indicate that depending on the type of application, only a marginal increase in latency of 2 to 5 ms is introduced for the added security. Layer wise traffic and packets captured between devices were analyzed. Channel utilization, message length distribution and message types were also evaluated. The proposed protocol's performance was found to be satisfactory on the two tested applications. Copyright © 2014 John Wiley & Sons, Ltd.     

Planning Tools for Special Networks

Hubbing has been shown to be an economical solution to the problems of providing both analog and digital special services. Digital cross-connect systems (DCS's) are an ideal vehicle for providing the hubbing function in a flexible and economic manner. However, planning hubbed networks with DCS's requires considerable analysis on a networkwide basis, a requirement difficult to carry out in a manual environment. This paper describes two strategic network planning tools that can aid network planners in determining the optimal hubbing configuration for their networks. HUBCAP (Hubbing Configuration Analysis Program) is a program that analyzes analog special services networks. SUBCAP (Subrate Configuration Analysis Program) examines networks designed for digital data services. The capabilities and application of each of the tools are discussed. Because the transmission equipment has the capabilities to support both types of services, and since shared applications are becoming increasingly popular, it is important to optimize the total network.     

Energy‐efficient network selection with mobility pattern awareness in an integrated WiMAX and WiFi network

To provide wireless Internet access, WiFi networks have been deployed in many regions such as buildings and campuses. However, WiFi networks are still insufficient to support ubiquitous wireless service due to their narrow coverage. One possibility to resolve this deficiency is to integrate WiFi networks with the wide‐range WiMAX networks. Under such an integrated WiMAX and WiFi network, how to conduct energy‐efficient handovers is a critical issue. In this paper, we propose a handover scheme with geographic mobility awareness (HGMA), which considers the historical handover patterns of mobile devices. HGMA can conserve the energy of handovering devices from three aspects. First, it prevents mobile devices from triggering unnecessary handovers according to their received signal strength and moving speeds. Second, it contains a handover candidate selection method for mobile devices to intelligently select a subset of WiFi access points or WiMAX relay stations to be scanned. Therefore, mobile devices can reduce their network scanning and thus save their energy. Third, HGMA prefers mobile devices staying in their original WiMAX or WiFi networks. This can prevent mobile devices from consuming too much energy on interface switching. In addition, HGMA prefers the low‐tier WiFi network over the WiMAX network and guarantees the bandwidth requirements of handovering devices. Simulation results show that HGMA can save about 59– 80% of energy consumption of a handover operation, make mobile devices to associate with WiFi networks with 16–62% more probabilities, and increase about 20–61% of QoS satisfaction ratio to handovering devices. Copyright © 2009 John Wiley & Sons, Ltd.     

运营商网络中面向资源碎片优化的网络服务链构建策略

网络功能虚拟化(NFV)的引入使得运营商网络的网络功能不再依赖于专用硬件设备且服务能力更具弹性。为更有效地使用基于NFV的运营商网络中的资源,该文提出一种网络服务链(NSC)的优化构建策略。和已有研究工作不同,该文从减少因计算资源和网络资源这两类资源的不合理使用产生的资源碎片角度出发,以最大化运营商网络能容纳的业务流数量为目标,建立NSC构建的数学模型,且提出一种新的贪心NSC构建策略,该策略融合了路径选择和NSC的多个VNF部署。数值仿真实验表明,在相同资源总量的情况下与典型策略相比,所提策略能够容纳更多的业务流,实现更低的端到端的数据延迟,有效提高了运营商网络中通用服务器和交换机的资源利用率。     

An Architecture for Exploiting Multihoming in Mobile Devices for Vertical Handovers & Bandwidth Aggregation

In recent years, mobile devices with multihoming capabilities i.e. equipped with multiple network interfaces have gained large scale popularity. This multihoming capability enables the mobile devices to connect with multiple diverse access networks simultaneously. However, networking protocol stack implemented in current devices is not capable of exploiting the availability of multiple network interfaces. Multihoming can be used to provide two important services: vertical handovers and bandwidth aggregation. Vertical handover enables a multihomed device to switch its connectivity from one access network to another access network without disrupting the communication session. Bandwidth aggregation enables multihomed device to achieve higher throughput by establishing simultaneous connections over multiple available network interfaces. A number of solutions have been proposed to exploit multihoming for vertical handovers and bandwidth aggregation. However, most of these solutions either require the support of additional network entities such as host agent, foreign agent, mobility gateway, proxy, etc. or they require changes in current widely deployed protocol stack in operating system kernels. Dependence on either network operator, administrator or operating system vendors hinders the large scale deployment of these solutions. This paper presents an end-to-end architecture that offers the vertical handover and bandwidth aggregation services to TCP applications. This architecture neither requires any additional network entity nor it requires the changes in current networking protocol stack in operating system kernels. The paper presents the design, implementation and performance analysis of the proposed architecture.     

A venues‐aware message routing scheme for delay‐tolerant networks

With their proliferation and increasing capabilities, mobile devices with local wireless interfaces can be organized into delay‐tolerant networks (DTNs) that exploit communication opportunities arising out of the movement of their users. As the mobile devices are usually carried by people, these DTNs can also be viewed as social networks. Unfortunately, most existing routing algorithms for DTNs rely on relatively simple mobility models that rarely consider these social network characteristics, and therefore, the mobility models in these algorithms cannot accurately describe users’ real mobility traces. In this paper, we propose two predict and spread (PreS) message routing algorithms for DTNs. We employ an adapted Markov chain to model a node's mobility pattern and capture its social characteristics. A comparison with state‐of‐the‐art algorithms demonstrates that PreS can yield better performance in terms of delivery ratio and delivery latency, and it can provide a comparable performance with the epidemic routing algorithm with lower resource consumption. Copyright © 2013 John Wiley & Sons, Ltd.     

A novel self-routing address scheme for all-optical packet-switched networks with arbitrary topologies

Pure all-optical packet-switched networks in which both header processing and packet routing are carried out in the optical domain overcome the bandwidth bottlenecks of optoelectronic conversions and therefore are expected to meet the needs of next generation high speed networks. Due to the limited capabilities of available optical logic devices, realizations of pure all-optical packet-switched networks in the near future will likely employ routing schemes that minimize the complexity of routing control. In this paper, we propose a novel self-routing scheme that identifies the output ports of the nodes in a network instead of the nodes themselves. The proposed address scheme requires single bit processing only and is applicable to small to medium size pure all-optical packet-switched networks with arbitrary topologies. Unlike traditional self-routing schemes, multiple paths between two nodes can be defined. An hierarchical address structure can be used in the proposed routing scheme to shorten the address.     

Co-opetition Enabling Security for Cooperative Networks: Authorizing Composition Agreement Negotiations between Ambient Networks

Networks are under control of different authorities because of ownership. To flexibly use capabilities across network borders or to even change border, decisions are needed that effect the autonomy of organizations, which have the authority to control their networks. Co-opetition, on the other hand, where a network of stakeholders co-operate and compete to create maximum value, is one of the most important business perspectives of recent years. To support co-opetition, flexibly use of capabilities across network borders is helpful. Network composition enables to share capabilities between different networks. Determining which capabilities are desired and allowed to be shared is here understood as the result of a composition process. This composition process may encompass negotiations or it can be based on matching predefined profiles. Any non manual, adequately secured composition process between networks of different authorities, however, needs an authorization for such composition to happen between authenticated networked partners. This article presents the approach and procedure for authorizing the negotiations between networks that want to compose to improve the network owner position regarding co-opetition.