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1.
With the mobile communication market increasingly moving towards value-added services, the network cost will need to be included
in the service offering itself. This will lead service providers to optimize network usage based on real cost rather than
simplified network plans sold to consumers traditionally. Meanwhile, today’s mobile devices are increasingly containing multiple
radios, enabling users on the move to take advantage of the heterogeneous wireless network environment. In addition, we observe
that many bandwidth intensive services such as video on demand and software updates are essentially non real-time and buffers
in mobile devices are effectively unlimited. We therefore propose EMUNE, a new transfer service which leverages these aspects.
It supports opportunistic bulk transfers in high bandwidth networks while adapting to device power concerns, application requirements
and user preferences of cost and quality. Our proposed architecture consists of an API, a transport service and two main functional
units. The well defined API hides all internal complexities from a programmer and provides easy access to the functionalities.
The prediction engine infers future network and bandwidth availability. The scheduling engine takes the output of the prediction
engine as well as the power and monetary costs, application requirements and user preferences into account and determines
which interface to use, when and for how long for all outstanding data transfer requests. The transport service accordingly
executes the inferred data transfer schedule. The results from the implementation of EMUNE’s and of the prediction and scheduling
engines evaluated against real user data show the effectiveness of the proposed architecture for better utilization of multiple
network interfaces in mobile devices. 相似文献
2.
Wireless messaging is an integral component of universal personal communication services (PCSs). Its growth is likely to be further fueled by the availability of new data capabilities in the new PCS air interfaces. Our research focuses on high-level issues such as new messaging functionalities, high-layer protocols, and overall system design. Pigeon is our proposal of a wireless two-way messaging system. The novelty of our system lies in: (1) the techniques used in mitigating the wireless media and end device constraints, (2) the functionalities provided, and (3) its modular architecture. Examples of (1) include the use of asymmetric protocols and the introduction of user agents. Examples of (2) include group addressing, transaction support, and flexible messages. The modularity of Pigeon allows its individual components to be adopted by specific systems, A prototype of Pigeon has been implemented, and is operational at Bell Laboratories. We describe the motivation, design, and functionality of Pigeon. We also present, as an example, a mapping of Pigeon to a standard cellular/PCS messaging system 相似文献
3.
Service providers, especially in the mobile entertainment domain, are facing increasing competition. The ability to design, develop, and deploy unique context-aware entertainment services fast and easily as well as the capability to provide intuitive user interfaces becomes essential for market players. Furthermore, today's mobile world is made up of heterogeneous networks accessible via various devices with different characteristics. Progressive users have the desire to utilize the same services and access the same information content on all available devices. At the same time, service providers have to diversify their services in order to remain competitive and attract the various customer segments making up the mass market. We introduce an agent-based serviceware framework to assist service providers in developing innovative services, thus reducing the time to market of the respective applications. The realized serviceware framework offers personalization, location awareness, and the multi-access service platform, a flexible solution for ubiquitous service access. Thus, our solution allows a heterogeneous landscape of end devices to access an application server's mobile services in a multimodal, multilingual, and multimedia-based manner. We describe the utilization of the different modules of the service framework as well as the BerlinTainment application, an entertainment planning system based on the framework. 相似文献
4.
This article describes the design and implementation of a unique cooperative agents testbed aimed at addressing diverse applications for the difficult problem of seamless personal information networking (SPIN). The real-world SPIN testbed is aimed at two difficult applications. Namely seamless messaging and intelligent network management. Both applications are agent-driven and share agent behavior, and the messaging agents rely on the network management device diagnostic agents for input. The article introduces both problem areas in a common testbed. The first-generation seamless messaging application is described in detail. User-centric seamless messaging assumes heterogeneous communication environments intended to support today's nomadic users. The prototype is introduced for the management of messages across distributed information networks. Its aim is to intercept, filter, interpret, and deliver multimodal messages, be they voice, fax, video, and/or e-mail messages. A user's personal communication agent is charged with delivering messages to the recipient regardless of their target messaging device-a telephone, pager, desktop, wireless laptop, or wireless phone. Personal communication agents classify and act on incoming messages based on their content. A secretary agent routes and tailors urgent messages appropriately to the device manager agent, which delivers the message to a device on which the user may be roaming or active. What makes the seamless messaging application unique is its approach to treating a message in a universal manner, and its ability to mediate between different messaging environments and devices, and to try to track and find the user 相似文献
5.
The communications industry significantly lags behind the personal computing industry in terms of empowering the end user to innovate, as fundamental architectural shifts have yet to occur to push intelligence to the network edge. The decentralization of the telecommunication system to the edge of today's hierarchically formed networks is inevitable with the emergence of key wireless technologies and the proliferation of mobile computing devices and more prevailing usage models. This article envisions a decentralized communication system formed of wireless mesh networks and a highly virtualized, converged computing and communications node-based architecture with emergent management capabilities. We propose to embed the user inside the network to freely associate services and resources such as computing, storage, and bandwidth to rapidly advance network innovation - network-centric computing. This article proposes a novel direction and vision for network-centric computing, expands upon our research, and presents the OverMesh platform from which we have begun work to instantiate this vision. Finally, we expect this new envisioned network to coexist with today's Internet infrastructure and enable a new generation of applications and usage models 相似文献
6.
The move towards service-oriented architectures and the increasing usage of mobile devices to access such services are two of the major changes in modern computing. Information about the user, their location and their trajectory can provide additional context information to a service, leading to useful applications such as directing a user to the nearest bus stop and displaying which buses are due to arrive in the next minutes. While this type of information can be useful, when the offered services are trusted, it also introduces privacy issues relating to gathering of location information for non-trusted applications like location-based marketing or user behaviour profiling. Users can limit their location information provided to a service but these controls are simple, making it important for the user to understand how their location information is being used by services. This paper reviews some of the methods currently being proposed to reduce the impact of location tracking on user privacy, and presents a novel encryption method for preserving the location and trajectory path of a user using Privacy-Enhancing Technologies. 相似文献
8.
Technology has been advancing day by day and smart phones are providing challenges for the development of latest and sophisticated mobile applications. Talkback feature of Android makes it easy to access touch screen devices, but specially abled people are facing various problems in existing mobile applications. All mobile applications are not following the feature of Talkback and there is a lack of tactile feature. Considering these points, the present study is an attempt to develop a mobile application based on voice and gestures to provide communication services to specially abled people. The mobile application has been developed with the help of android studio and a special mobile case. The mobile case designed to help the beginners of developed mobile application. Color combination technique of green computing has been used to design the layout of mobile application for saving power. Four edge method has also been used in the designing part of mobile application’s layout to make it more accessible. The findings of the study revealed that the developed mobile application helps the end user to access features of mobile phone such as call, message, date, time etc. The developed mobile application assists the specially abled people having visual impairment or totally blind. The paper elaborates the design and development phase of mobile application in detail. Furthermore, applications of developed mobile applications have also been highlighted. 相似文献
9.
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. 相似文献
10.
The need for fast treatment of patients in critical conditions motivates the use of mobile devices to provide prompt and consistent communication between hospitals and physicians. We propose a framework that supports ubiquitous access to medical systems using personalized mobile services and integrated medical systems. The proposed service-oriented medical framework provides dynamically composed services that are adapted to contextual variables such as the user’s role, the network bandwidth, and resources available at mobile devices while supporting task allocation in distributed servers for massive resource-consuming services. It also manages accurate patient data by integrating local medical systems using medical information standards such as Digital Imaging and Communications in Medicine and Health Level 7. We have demonstrated the effectiveness of our framework by building a prototype of context-based adaptation of computerized tomography image retrieval for acute stroke treatments, which allows images to be viewed on mobile devices with WiMax wireless network. The proposed medical framework reduces hospital delays of patients and facilitates treatments in the absence of medical specialists. 相似文献
11.
The web is going mobile, and the scope of mobile communication is widening tremendously, thus paving the way for a wide array of new forms of mobile device use. However, not every user is necessarily all the time taking advantage of the expanded affordances of mobile devices. Texting and phoning are still the predominant services in mobile communication. Previous research has argued that different styles of mobile communication are related to different user lifestyles. Thus, a remapping and matching of the landscape of mobile communication in relation to user lifestyles seems necessary. In this paper, we take one step back and first consider the instances in which lifestyles become behavior; i.e. actual usage situations of mobile communication. We outline three empirically deduced types of mobile communication usage situations, as well as three types of mobile web usage situations, to shed light on the instant at which lifestyle becomes behavior; i.e. at which specific usage situations of mobile communication actually occur. 相似文献
12.
This paper proposes iMobile, a proxy‐based platform for developing mobile services for various mobile devices and wireless access technologies. iMobile acts as a message gateway that allows mobile devices to relay messages to each other through various protocols on different access networks. It allows mobile devices to access internet services, corporate databases and to control various network devices. iMobile implements three key abstractions: dev‐let, info‐let and app‐let. An info‐let provides abstract view of information space. An app‐let implements service or application logic by processing information from various info‐lets. A dev‐let receives and sends messages through any particular protocols for mobile devices. The let engine supports user and device profiles for personalization and transcoding, and invokes proper app‐lets and info‐lets to answer requests from a dev‐let. The iMobile modular architecture allows developers to write device drivers, information access methods and application logic independently from each other. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
13.
Personal communications services (PCS) promise to provide a variety of information exchanges among users with any type of mobility, at any time, in any place, through any available device. To achieve this ambitious goal, two of the major challenges in the system design are: (i) to provide a high-speed wireless subsystem with large capacity and acceptable quality-of-service (QoS) and (ii) to design a network architecture capable of supporting multimedia traffic and various kinds of user mobility. A time-hopping spread-spectrum wireless communication system called ultra-wide bandwidth (UWB) radio is used to provide communications that are low power, high data rate, fade resistant, and relatively shadow free in a dense multipath environment. Receiver-signal processing of UWB radio is described, and performance of such communications systems, in terms of multiple-access capability, is estimated under ideal multiple-access channel conditions. A UWB-signal propagation experiment is performed using the bandwidth in excess of 1 GHz in a typical modern office building in order to characterize the UWB-signal propagation channel. The experimental results demonstrate the feasibility of the UWB radio and its robustness in a dense multipath environment. A ATM network is used as the backbone network due to its high bandwidth, fast switching capability, flexibility, and well-developed infrastructure. To minimize the impact caused by user mobility on the system performance, a hierarchical network-control architecture is postulated. A wireless virtual circuit (WVC) concept is proposed to improve the transmission efficiency and simplify the network control in the wireless subsystem. The key advantage of this network architecture and WVC concept is that the handoff can be done locally most of the time, due to the localized behavior of PCS users 相似文献
14.
This paper discusses current status and recent advancements of 3D graphics on mobile platforms and describes open issues concerning its usage in different applications. We have treated two particular application fields. Firstly, we deal with problems of visualization of complex data structures on mobile devices. The implementation of a 3D visualization renderer on the Symbian platform for mobile devices is written as a C++ application and based on the DieselEngine ® as a rendering engine. 3D visualization of data is generated in the form of a Virtual Reality Modelling Language (VRML) file meaning that actually any kind of 3D content written in VRML file format can be rendered on such a device. It was the result of a project the objective of which was to provide a user interface on a mobile platform displaying visualization of hierarchical Grid monitoring data. Secondly, we describe the system that brings face animation to embedded platforms. Face animation is considered to be one of the toughest tasks in computer animation today and its delivery to mobile platforms brings possibilities for development of new innovative and attractive services for the mobile market. 相似文献
15.
As many geo-located Web services will be deployed in the future, mobile clients will be interested in locating a specific application server based on requirements such as proximity, service cost per location area, bandwidth, and server utilization rates. This paper presents a middleware system called GLWSA (Geo-Located Web Services Architecture) that aims to satisfy these requirements in addition to providing a thematic factorization of common location functions in order to locate mobile clients. The GLWSA supports a set of GLWSMs (Geo-Located Web Services Manager) distributed over the mobile network. It defines protocols to discover and inform a Supplier Application Server (SAS) to migrate the service execution (from a specific client) to the nearest SAS based on the client's location. This architecture is suitable to assist mobile clients to discover the geo-located Web services and to maintain the service execution closest to their location. 相似文献
16.
This paper describes a novel mobile virtual-distrubuted system architecture for supporting global mobile computing and communications. the principal contribution of this paper is to innovatively apply virtual memory concepts to mobile systems by deploying mobile-floating agents to de-couple services and resources from the underlying network and allow them to move around following their mobile users. The mobile-floating agents maintain data structures associated with a mobile user. By combining the mobile-floating agent functions with a predictive mobility management algorithm and location-aware caching and prefetching, services and user data structure are pre-connected and pre-assigned at the locations to which the user is moving. Thus, the users can maintain their data structures or immediately receive service with virtually the same efficiency as at the previous location. 相似文献
17.
Developing widely useful mobile computing applications presents difficult challenges. On one hand, mobile users demand intuitive user interfaces, fast response times, and deep relevant content. On the other hand, mobile devices have limited processing, storage, power, display, and communication resources. Vindigo has taken a technology-intensive approach to meeting these challenges and has created personal navigation tools that many people find useful in their everyday lives. Vindigo's Palm OS application, introduced in March 2000, has hundreds of thousands of users and continues to attract new users rapidly. This article presents some of the technology behind Vindigo. To provide context, it first gives an overview of a typical user session. It then discusses special demands and constraints placed on mobile applications, and enumerates design principles drawn from these considerations. The rest of the article describes technology developed at Vindigo according to those principles. Throughout, it emphasizes techniques that have proven effective in delivering location-based services on today's handheld devices. 相似文献
19.
The success of the Internet has attracted more people to take part in network navigation. Numerous wireless-communication devices have rapidly evolved in the past decade. The demand for mobile communications is increasing and packet data services through Internet protocol (IP) networks have become a trend. To supply more IP addresses to network devices and improve network performance, a new IP version 6 (IPv6) was developed by the Internet Engineering Task Force in 1994. IPv6 supports certain features that make mobility management more efficient in mobile IP. A cellular architecture is needed to improve the communications quality and to reduce power consumption, both at the base and mobile stations. In a cellular environment, handoffs occur frequently. Reducing the defects caused by handoffs is extremely important in the mobile network environment. This is especially important for high-speed moving devices. In this paper, a handoff strategy called neighbor-assisted agent architecture, which takes advantage of the ad-hoc network to improve handoff performance, is proposed. Timing analytical and simulation results show that the proposed mechanism can provide a better solution than mobile IP for handoff breaks during high-speed movement. 相似文献
20.
Payment methods using mobile devices instead of using traditional methods (cash, credit card, etc) has been gaining popularity all over the world. The ubiquitous nature of smartphones and tablets has widened the ambit for using these devices for payments and other daily life activities. Recent advancements in mobile technology along with the convenience of mobile devices made these applications possible. Despite the worldwide user adoption of mobile applications, security is the key challenge in mobile banking and payments system. Mobile payments systems need to be very efficient and provide utmost security endlessly. State‐of‐the‐art mobile payment systems need the physical presence of a merchant agent to make a payment. In this article, we had described in detail about the design and implementation of a mobile payments application, used to make in‐store purchases and make secure payments without any physical presence of a cashier or a merchant agent. We proposed a novel privacy‐preserving and secure authentication algorithm to make mobile payments using biometrics. The analysis and experimental results show the reliability and efficiency of our proposed solution. 相似文献
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