Object Request Brokers in Mobile Computing

The widespread use of wireless and mobile networks and devices requiresspecial programming techniques and solutions. The object request brokers ofmobile environments have to adopt these techniques and offer servicesdealing with the problems of mobility. Most of the existing object request brokers however were developed for fixed networks assuming reliable transport protocols (mostly TCP), while the mobile networks cannot offer high qualitytransport.In this paper we give an overview of the challenges and solutions in mobilecomputing and present our ORB(M) framework implementing services based onthe solutions. Extending the framework doesn't require the assistance of itsdevelopers, the user can implement application-specific semantic elementsand deploy various new methods bound to the process of remote invocation.The user can form arbitrary new invocation semantics based on these elementsand customise the invocation semantics used by a given method. Our newmobility-related semantic elements offer solutions to the challengesof mobility allowing the user to concentrate on theessential problems of the application and handling.     

Information collection services for QoS-Aware mobile applications

Efficient resource provisioning that allows for cost-effective enforcement of application QoS relies on accurate system state information. However, maintaining accurate information about available system resources is complex and expensive, especially in mobile environments where system conditions are highly dynamic. Resource provisioning mechanisms for such dynamic environments must therefore be able to tolerate imprecision in system state while ensuring adequate QoS to the end-user. In this paper, we address the information collection problem for QoS-based services in mobile environments. Specifically, we propose a family of information collection policies that vary in the granularity at which system state information is represented and maintained. We empirically evaluate the impact of these policies on the performance of diverse resource provisioning strategies. We generally observe that resource provisioning benefits significantly from the customized information collection mechanisms that take advantage of user mobility information. Furthermore, our performance results indicate that effective utilization of coarse-grained user mobility information renders better system performance than using fine-grained user mobility information. Using results from our empirical studies, we derive a set of rules that supports seamless integration of information collection and resource provisioning mechanisms for mobile environments. These results have been incorporated into an integrated middleware framework AutoSeC (Automatic Service Composition) to provide support for dynamic service brokering that ensures effective utilization of system resources over wireless networks.     

异构个人域网络中的服务发现机制

个人周边智能设备与移动业务的融合促进了服务发现机制的发展,智能设备的增加和移动性也使得现有服务发现机制很难在用户移动当中始终提供有效服务。在对个人周边的异构网络特征分析的基础上,利用组播和信息熔合等技术,提供了一套适用于节点具有群组移动性、异构性的动态网络的可靠的服务发现机制,并且不会消耗过多的系统带宽资源。     

PosCFS+: A Self‐Managed File Service in Personal Area Network

Wearable computers consisting of various small devices such as smart phones, digital cameras, MP3 players and specialized I/O devices in personal area networks will play an important role in future ubiquitous computing. In this environment, accessing user data is quite complex due to the dynamic and heterogeneous characteristics of the underlying networks. Moreover, since the amount of user data increases rapidly, automatic data backup management is also critical. To overcome these challenges, several studies have been conducted including our previously proposed file service system, PosCFS, which could be adapted to the requirements with a virtualization technique allowing per‐user global namespace for managing and accessing data stored on physical storage spaces detected in PAN. In this paper, we present a smart file service framework, PosCFS+ which is an improved and extended version of our previous work. Performance improvement is made possible by redesigning the metadata management scheme based on database and keywords rather than ontology. In addition, the automatic data replication management is newly designed based on the OSD protocol.     

A Context-Aware User Interface for Wireless Personal-Area Network Assistive Environments

The daily life of people with severe motor system impairments is challenging and thus often subordinated to extensive external help; increasing their level of self-support is thus highly desirable. Recent advances in wireless communications, in particular in wireless personal-area networks, serve as technological enablers well suited for implementing smart and convenient assistive environments which can increase self-support. This paper presents the design and prototyping of a versatile interface for such wireless assistive environments. We propose a modular framework that can accommodate several wireless personal-area network standards. The interface is built upon this framework and is designed in such a way that it can be controlled by various types of input devices such as a touch screen or a tongue-control unit. The interface can automatically discover consumer appliances (e.g. Zigbee and Bluetooth enabled lights and computers) in the user’s environment and display the services supported by these devices on a user-friendly graphical user interface. A demonstrator is prototyped and experimental results show that the proposed interface is context-aware, i.e. it successfully detects available appliances, adapts itself to the changes that occur in the user’s environment, and automatically informs the user about these changes. The results also show that the proposed interface is versatile and easy to use, i.e. the user can easily control multiple devices by means of a browser menu. Hence, the proposed work illustrates how assistive technology based on wireless personal-area networks can contribute to improving the quality of life of motor system impaired persons.     

Modeap: Moving Desktop Application to Mobile Cloud Service

Thanks to the availability of various mobile applications, lots of users shift from desktop environments, e.g., PCs and laptops, to mobile devices, e.g., smartphones and tablets. However, there are still some desktop applications without counterparts on mobile devices, such as some integrated development environments (e.g., eclipse) and automatic industry control systems. In this paper, we propose Modeap, a platform-independent mobile cloud service that can push all desktop applications developed for various operating systems from cloud servers to mobile devices. Modeap follows a design principle of complete detachment and regeneration of desktop user interface, i.e., the essential graphical primitives of the original desktop applications will be intercepted and then translated into standard web-based graphical primitives such that the interactions between users and remote cloud applications become possible via mobile web browsers. In this way, all desktop applications built upon the same set of graphical primitives can be used on mobile devices in great flexibility without installing any new software. We have developed a proof-of-concept prototype that provides Windows applications from cloud server to mobile web browsers. The results of extensive experiments show that the proposed framework can achieve our design goals with low latency and bandwidth consumption.     

Privacy Protected Spatial Query Processing for Advanced Location Based Services

Due to the popularity of mobile devices (e.g., cell phones, PDAs, etc.), location-based services have become more and more prevalent in recent years. However, users have to reveal their location information to access location-based services with existing service infrastructures. It is possible that adversaries could collect the location information, which in turn invades user’s privacy. There are existing solutions for query processing on spatial networks and mobile user privacy protection in Euclidean space. However there is no solution for solving queries on spatial networks with privacy protection. Therefore, we aim to provide network distance spatial query solutions which can preserve user privacy by utilizing K-anonymity mechanisms. In this paper, we propose an effective location cloaking mechanism based on spatial networks and two novel query algorithms, PSNN and PSRQ, for answering nearest neighbor queries and range queries on spatial networks without revealing private information of the query initiator. We demonstrate the appeal of our technique using extensive simulation results.     

Service configuration and user profiling in 4G terminals

This paper presents a middleware platform for managing devices that operate in heterogeneous environments. The proposed management framework supports terminal-controlled, preference-based access network selection. Two separate problems are identified in this domain: one involving the computation of optimal allocations of services to access networks and quality levels (service configuration), and one concerning the dynamic inference of the user’s preferences, according to the usage context (user profiling). This paper includes an approach to the definition, mathematical formulation and solution of both these problems. Indicative results of the proposed solution methods are presented in the context of a real-life scenario simulating a day in the life of an ordinary user.     

Towards centralized and semi‐automatic VLAN management

Virtual local area networks (VLANs) are widely used in many enterprises, campuses, and data‐centre networks. Although VLANs can restrict broadcast domains and contain hosts in one network or separate networks, the management of VLANs is an ad hoc and error‐prone work. In this paper, we design and implement a centralized and semi‐automatic system for VLAN management (CSS‐VM). Based on the physical network topology and user group (examples are engineering, student cluster, and faculty cluster) information, CSS‐VM can decide the number of VLANs that each user group would be partitioned into. In addition, CSS‐VM can not only monitor the status of devices and links but can also calculate an optimal spanning tree for each affected VLAN after a link or device failure is detected, so that it does not need to enable the Spanning Tree Protocol on devices but still has the ability of converging from device or link failures and avoiding bridging loops. We have evaluated CSS‐VM on the topology and VLAN partition data of an operational enterprise network. Our results show that CSS‐VM can obviously keep the broadcast traffic cost reasonable, efficiently partition and configure VLANs, quickly converge from link and device failures, and intelligently make a balanced use of links. Copyright © 2014 John Wiley & Sons, Ltd.     

Joint QoS-control and handover optimization in backhaul aware SDN-based LTE networks

Future cellular networks will be dense and require key traffic management technologies for fine-grained network control. The problem gets more complicated in the presence of different network segments with bottleneck links limiting the desired quality of service (QoS) delivery to the last mile user. In this work, we first design a framework for software-defined cellular networks and then propose new mechanisms for management of QoS and non-QoS users traffic considering both access and backhaul networks, jointly. The overall SDN-LTE system and related approaches are developed and tested using network simulator in different network environments. Especially, when the users are non-uniformly distributed, the results shows that compared to other approaches, the proposed load distribution algorithm enables at least 6% and 23% increase in the average QoS user downlink throughput and the aggregate throughput of 40% users with lowest throughput (edge users), respectively. Also, the proposed system efficiently achieves desired QoS and handles the network congestion without incurring significant overhead.

     

Media Gateway: bringing privacy to private multimedia cloud connections

The growing interest in media sharing combined with the explosion of social applications have opened an opportunity window for cloud based applications for media management as Media Cloud, described in this article, that has brought the concept of Cloud Computing to home environments. Media Cloud provides a comprehensive and efficient solution for managing content among federated home environments. As part of the purpose of empowering the user role as well as to improve user experience, we placed significant efforts on interoperability and privacy protection when it comes to accessing cloud resources from other networks. This article describes a solution that enables limited devices to access contents located in private clouds, as Media Cloud, with the cooperation of network providers,     

Certificate status validation in mobile ad hoc networks - [accepted from open call]

Certificate validation is much more complex in mobile ad hoc networks than in conventional networks because online access to trusted authorities is not always guaranteed. For this reason, we require new solutions to overcome both the lack of infrastructure and the limited capabilities of several user devices. In this article we study the application of different mechanisms for certificate validation in MANETs and present a cooperative mechanism for certificate validation suitable for MANETs.     

Prediction Mechanisms to Improve 5G Network User Allocation and Resource Management

As technology rapidly advances, the number of devices constantly communicating, transmitting and receiving data through the cellular networks keeps rising, posing an unprecedented load on them. Such an increase calls for establishing new methods to manage these devices as well as utilize the data produced by them to establish network architectures that can prevent cellular networks from overloading. To achieve the desired results, we need to optimally allocate network resources to existing users. Resource allocation has traditionally been considered an optimization problem where proposed solutions are hard to implement in real time, resulting in the use of inferior solutions with reduced produced performance. With the introduction of Machine Learning, we propose three mechanisms, intending to utilize network data to improve real time network performance. The first mechanism, a Decision Trees based mechanism aims to improve real time decision making by predicting the optimal matching of users and Base Stations. The second mechanism, a K-means based mechanism intends to tackle network congestion and ensure uninterrupted Quality of Service by predicting the optimal coordinates for placing Base Stations along the network based on traffic data. Finally, a Regression based mechanism manages to predict user movement along the network, resulting in improved resource management and reduced energy waste. These mechanisms can work cooperatively, essentially establishing a network architecture that utilizes prediction to efficiently allocate users and manage available resources.

     

面向移动云计算的自适应服务选择方法研究

Despite the rapid advances in mobile tech-nology, many constraints still prevent mobile de-vices from running resource-demanding applica-tions in mobile environments. Cloud computing with flexibility, stability and scalability enables ac-cess to unlimited resources for mobile devices, so more studies have focused on cloud computing- based mobile services. Due to the stability of wire-less networks, changes of Quality of Service (QoS) level and user' real-time preferences, it is becoming challenging to determine how to adaptively choose the “appropriate”service in mobile cloud compu-ting environments. In this paper, we present an a-daptive service selection method. This method first extracts user preferences from a service's evaluation and calculates the similarity of the service with the weighted Euclidean distance. Then, they are com-bined with user context data and the most suitable service is recommended to the user. In addition, we apply the fuzzy cognitive maps-based model to the adaptive policy, which improves the efficiency and performance of the algorithm. Finally, the experi-ment and simulation demonstrate that our approach is effective.     

An improved CAN fieldbus for industrial applications

The controller area network (CAN) was originally developed to support cheap and rather simple automotive applications. However, because of its performance and low cost, it is also being considered in automated manufacturing and process control environments to interconnect intelligent devices, such as modern sensors and actuators. Unfortunately, CAN, in its current form, is not able to either share out the system bandwidth among the different devices fairly or to grant an upper bound on the transmission times experienced by the nodes connected to the communication medium as it happens, for instance, in the token-based networks. In this paper, two slight modifications of the basic CAN protocol are presented that satisfy the above-mentioned requirements at the expense of a very small degradation of the system's performance. Both these solutions exhibit a high degree of compatibility with those devices which have already been designed for the conventional CAN fieldbus. Besides introducing the new mechanisms, this paper also presents some performance figures obtained using a specially developed software simulator, while the behavior of the new mechanisms is compared to the traditional CAN systems, in order to see how effective they are     

An ID‐based mutual authentication with key agreement protocol for multiserver environment on elliptic curve cryptosystem

Mutual authentication is used to validate the legitimacy of a remote login user and a server. Conventional user authentication protocols are suited to solve the privacy and security problems for the single client/server architecture environment. However, the use of computer networks and information technology has grown spectacularly. More and more network architectures are used in multi‐server environments. Recently, several authentication schemes for multi‐server environments have been proposed. However, the performance of these schemes is not suitable for applications. To improve the performance, we propose a new ID‐based mutual authentication protocols for multi‐server environment without bilinear pairings. We also show that the proposed scheme is provable secure in the random oracle model. Copyright © 2012 John Wiley & Sons, Ltd.     

An independent three‐factor mutual authentication and key agreement scheme with privacy preserving for multiserver environment and a survey

In the past decades, the demand for remote mutual authentication and key agreement (MAKA) scheme with privacy preserving grows rapidly with the rise of the right to privacy and the development of wireless networks and Internet of Things (IoT). Numerous remote MAKA schemes are proposed for various purposes, and they have different properties. In this paper, we survey 49 three‐factor–based remote MAKA schemes with privacy preserving from 2013 to 2019. None of them can simultaneously achieve security, suitability for multiserver environments, user anonymity, user untraceability, table free, public key management free, and independent authentication. Therefore, we propose an efficient three‐factor MAKA scheme, which achieves all the properties. We propose a security model of a three‐factor–based MAKA scheme with user anonymity for multiserver environments and formally prove that our scheme is secure under the elliptic curve computational Diffie‐Hellman problem assumption, decisional bilinear Diffie‐Hellman problem assumption, and hash function assumption. We compare the proposed scheme to relevant schemes to show our contribution and also show that our scheme is sufficiently efficient for low‐power portable mobile devices.     

Improving assurance of a sustainable route-split MANET routing by adapting node battery exhaustion

Assurance networks are designed to realize trustable Internet-Of-Things including terminal devices/infrastructure service applications for new generation networks. To construct assurance networks, it is necessary to evaluate them quantitatively. In this paper, we provide one of case studies to evaluate them quantitatively. In mobile ad hoc networks (MANETs), the network environments change over time due to the movement of nodes, the battery level of nodes, and so on. Assurance networks must maintain high performance even when such diverse changes of the network environments occur in the widely applicable domain. And if their performance degrades, they must early recover from the changes. So far, we have proposed a routing method for MANETs, called Route-Split Routing (RSR). RSR can suppress escalation of control packets in large scale MANETs. However, with RSR, drawbacks occur when some nodes exhaust their batteries. In this paper, we propose a sustainable route-split routing scheme to improve assurance by adapting node faults due to battery exhaustion for MANETs. To evaluate the assurance of the proposed method, we have implemented it with a simulator and have conducted simulation experiments. The results indicate that the proposed method can maintain high throughput when some nodes experience various levels of battery power and power consumption and even when some nodes die simultaneously.     

An efficient authentication system of smart device using multi factors in mobile cloud service architecture

Mobile cloud computing environments have overcome the performance limitation of mobile devices and provide use environments not restricted by places. However, user information protection mechanisms are required because of both the security vulnerability of mobile devices and the security vulnerability of cloud computing. In this paper, a multifactor mobile device authentication system is proposed to provide safety, efficiency, and user convenience for mobile device use in cloud service architectures. This system improves security by reinforcing the user authentication required before using cloud computing services. Furthermore, to reinforce user convenience, the system proposed increases the strength of authentication keys by establishing multiple factors for authentication. For efficient entries in mobile device use environments, this system combines mobile device identification number entries, basic ID/password type authentication methods, and the authentication of diverse user bio‐information. This system also enhances authentication efficiency by processing the authentication factors of a user's authentication attempt in a lump instead of one by one in the cloud computing service environment. These authentication factors can be continuously added, and this authentication system provides authentication efficiency even when authentication factors are added. The main contribution is to improve high security level by through authentication of mobile devices with multifactors simultaneously and to use the mobile cloud service architecture for its efficient processing with respect to execution time of it. Copyright © 2013 John Wiley & Sons, Ltd.     

Performance enhancement of combining QoS provisioning and location management in wireless cellular networks

Quality-of-service (QoS) provisioning and location management (LM) in cellular networks are solved separately in previous work. For realistic network environments, we have proposed a framework of combining QoS provisioning and LM by using all available user mobility information. In this paper, we present performance evaluation to show that this framework can yield more efficient solutions for both. We propose a novel path-based LM scheme in this combined framework and evaluate the performance gain of the new scheme over the original path-based LM scheme by simulations. Further, we propose a new connection admission control (CAC) scheme derived from this combined framework for QoS provisioning and present results showing performance enhancements over CAC schemes proposed previously.