PerCom 2004: Promoting the Pervasive Computing Paradigm

PerCom 2004's theme was the emergence of the pervasive computing and communications paradigm with the goal of providing computing and communication services all the time, everywhere. The featured research represented the advances in pervasive computing and communications, including wireless networks, mobile computing, distributed computing, and agent technologies that will help realize this goal.     

Improved Key Agreement Based Kerberos Protocol for M-Health Security

The development of wireless sensor network with Internet of Things (IoT) predicts various applications in the field of healthcare and cloud computing. This can give promising results on mobile health care (M-health) and Telecare medicine information systems. M-health system on cloud Internet of Things (IoT) through wireless sensor network (WSN) becomes the rising research for the need of modern society. Sensor devices attached to the patients’ body which is connected to the mobile device can ease the medical services. Security is the key connect for optimal performance of the m-health system that share the data of patients in wireless networks in order to maintain the anonymity of the patients. This paper proposed a secure transmission of M-health data in wireless networks using proposed key agreement based Kerberos protocol. The patients processed data are stored in cloud server and accessed by doctors and caregivers. The data transfer between the patients, server and the doctors are accessed with proposed protocol in order to maintain the confidentiality and integrity of authentication. The efficiency of the proposed algorithm is compared with the existing protocols. For computing 100 devices it consumes only 91milllisecond for computation.     

基于移动Agent的无线移动计算模型及应用

传统的分布式计算模型客户/服务器模型不适应无线移动计算环境,文中详细分析了扩展的客户/服务器模型及其存在的问题。在此基础上将移动agent应用到扩展的客户/服务器模型,无线移动计算的性能得到了改善。文中还分析了基于移动agent的无线移动计算模型的特点,其中最重要的一点是信息和服务完全分离。最后将基于移动agent的无线移动计算模型应用到移动电子商务系统,设计了一个产品电子交易的原型。     

基于移动Agent的无线移动计算模型及应用

传统的分布式计算模型客户／服务器模型不适应无线移动计算环境，文中详细分析了扩展的客户／服务器模型及其存在的问题。在此基础上将移动agent应用到扩展的客户／服务器模型，无线移动计算的性能得到了改善。文中还分析了基于移动agent的无线移动计算模型的特点，其中最重要的一点是信息和服务完全分离。最后将基于移动agent的无线移动计算模型应用到移动电子商务系统．设计了一个产品电子交易的原型。     

An authentication protocol offering service anonymity of mobile device in ubiquitous environment

With the advent of ubiquitous era, various devices and services using wireless network are increasing. For communications in wireless network, mobile devices are used and various services are increasingly provided through mobile devices. The AAA (Authentication, Authorization, and Accounting) that authorizes and manages the mobile devices is processing the standardization for various application services for the purpose of the standardization of authentication, authorization, and accounting to provide safety and reliability of various services and protocols of both wired and wireless network. However, even if AAA exists the development of network varies vulnerabilities and attack types, and accordingly the exposure of information appears as the biggest problem. Therefore, this study suggests the safe authentication method that protects against information exposure by guaranteeing anonymity of service with temporal ID, and provides efficiency because AAA authentication server is based on the ticket given to a service server without the need of re-authentication when mobile node authorized from the AAA authentication server receives service.     

The “Always Best Packet Switching” architecture for SIP-based mobile multimedia services

This paper presents a distributed architecture for the provision of seamless and responsive mobile multimedia services. This architecture allows its user applications to use concurrently all the wireless network interface cards (NICs) a mobile terminal is equipped with. In particular, as mobile multimedia services are usually implemented using the UDP protocol, our architecture enables the transmission of each UDP datagram through the “most suitable” (e.g. most responsive, least loaded) NIC among those available at the time a datagram is transmitted. We term this operating mode of our architecture Always Best Packet Switching (ABPS). ABPS enables the use of policies for load balancing and recovery purposes. In essence, the architecture we propose consists of the following two principal components: (i) a fixed proxy server, which acts as a relay for the mobile node and enables communications from/to this node regardless of possible firewalls and NAT systems, and (ii) a proxy client running in the mobile node responsible for maintaining a multi-path tunnel, constructed out of all the node's NICs, with the above mentioned fixed proxy server. We show how the architecture supports multimedia applications based on the SIP and RTP/RTCP protocols, and avoids the typical delays introduced by the two way message/response handshake of the SIP signaling protocol. Experimental results originated from the implementation of a VoIP application on top of the architecture we propose show the effectiveness of our approach.     

Smart devices and spaces for pervasive computing

Applications and services for pervasive computing have been dramatically grown and have contributed extensively to our daily experiences in recent years. Smart systems, devices, and spaces are proactive for ubiquitous and pervasive computing. Smart information technology (IT) is also an outcome of the state of the art and novel mobile and ubiquitous computing technologies that include highly capable handheld device, pervasive and personal device, etc. This special issue will be a trigger for further related research and technology improvements in pervasive and ubiquitous computing using smart devices and services. This special issue called for original papers describing the latest developments, trends, and solutions of smart devices and spaces for pervasive computing including real-time operating systems (OS), tiny OS and middleware supports, mobile system performance, trustworthy Internet and communications, agents and mobile and pervasive services, among others. In particular, this special issue focuses on a remote control and media-sharing system, flash storage-based smart system, heterogeneous mobile OS, and prediction and auto-execution system for pervasive computing.     

Executing mobile applications on the cloud: Framework and issues

Modern mobile devices, such as smartphones and tablets, have made many pervasive computing dreams come true. Still, many mobile applications do not perform well due to the shortage of resources for computation, data storage, network bandwidth, and battery capacity. While such applications can be re-designed with client–server models to benefit from cloud services, the users are no longer in full control of the application, which has become a serious concern for data security and privacy. In addition, the collaboration between a mobile device and a cloud server poses complex performance issues associated with the exchange of application state, synchronization of data, network condition, etc. In this work, a novel mobile cloud execution framework is proposed to execute mobile applications in a cloud-based virtualized execution environment controlled by mobile applications and users, with encryption and isolation to protect against eavesdropping from cloud providers. Under this framework, several efficient schemes have been developed to deal with technical issues for migrating applications and synchronizing data between execution environments. The communication issues are also addressed in the virtualization execution environment with probabilistic communication Quality-of-Service (QoS) technique to support timely application migration.     

A system for the provision of medical diagnostic and treatment advice in home care environment

Healthcare is an increasingly collaborative enterprise, involving broad range of healthcare services provided by many individuals and organizations. Apart from the provision of healthcare services to patients during hospitalization, the ability to assist people who have healthcare needs at their homes (e.g., the elderly) has become an increasingly critical issue. Provision of such personalized medical care services to patients requires readily access to integrated healthcare services ubiquitously. The integration of mobile and wireless devices with Grid technology can provide ubiquitous and pervasive access to Grid services. This article presents MASPortal, a Grid portal application for the assistance of people who are in need of medical advice at their homes. MASPortal is designed for use with wireless Personal Digital Assistants (PDAs) and provides remote access to an automated medical diagnostic and treatment advice system via an adaptive and easy to use interface. MASPortal has been implemented with a multi-layered security infrastructure in order to ensure secure access to healthcare processes and sensitive patient data.     

Incremental View Maintenance for Mobile Databases

In a mobile environment, querying a database at a stationary server from a mobile client is expensive due to the limited bandwidth of a wireless channel and the instability of the wireless network. We address this problem by maintaining a materialized view in a mobile client's local storage. Such a materialized view can be considered as a data warehouse. The materialized view contains results of common queries in which the mobile client is interested. In this paper, we address the view update problem for maintaining the consistency between a materialized view at a mobile client and the database server. The content of a materialized view could become incoherent with that at the database server when the content of the database server and/or when the location of the client is changed. Existing view update mechanisms are ‘push-based’. The server is responsible for notifying all clients whose views might be affected by the changes in database or the mobility of the client. This is not appropriate in a mobile environment due to the frequent wireless channel disconnection. Furthermore, it is not easy for a server to keep track of client movements to update individual client location-dependent views. We propose a ‘pull-based’ approach that allows a materialized view to be updated at a client in an incremental manner, requiring a client to request changes to its view from the server. We demonstrate the feasibility of our approach with experimental results. Received 27 January 1999 / Revised 26 November 1999 / Accepted 17 April 2000     

SPECSA: a scalable, policy-driven, extensible, and customizable security architecture for wireless enterprise applications

This paper presents SPECSA, a new, optimized, policy-driven security architecture for wireless enterprise applications. SPECSA is scalable, extensible, flexible, and customizable. It supports end-to-end client authentication, data integrity and confidentiality between wireless clients and enterprise servers. The security services provided by SPECSA are customized and controlled by an easily configurable security policy that specifies several security-related attributes, classifies network data based on sensitivity and content, and provides an abstraction for the communication and messaging between the client and the server. In addition, SPECSA provides a standard Application Programming Interface (API) that conceals to a great extent the complexity of security operations and programming from the application developer who may not be experienced with enterprise security programming. SPECSA was designed in a platform-neutral manner and can be implemented on a wide range of wireless clients ranging from low-end platforms such as the Java 2 Mobile Edition/Connected Limited Device Configuration (J2ME/CLDC) on limited-memory mobile devices to Personal Java and the Net Compact Framework on PDAs. On the server side, SPECSA can be implemented on any of the available enterprise server platforms. A sample implementation of SPECSA was developed for J2ME on the client-side and for Java 2 Enterprise Edition (J2EE) on the server-side.     

无线移动环境中基于移动Agent的实时构件组装机制研究

由于无线网络较窄、昂贵的带宽，及移动设备自身有限的硬件能力，在无线移动环境中进行实时构件组装调用时面临着更多的技术挑战，需要一种高效、可靠的机制给予支持。本文提出一种基于移动Agent的无线网络环境构件组装调用机制。该机制利用移动Agent作为移动客户端与构件服务器之间交互的中介，提供了灵活、可配置的组装结构，从而有效避免移动客户端不必要的访问操作，节省了移动客户端的无线网络连接开销，与其他机制相比有着较高的执行效率；同时该机制可有效支持移动客户端发生故障后的状态恢复，从而确保运行过程的可靠性。最后本文通过实验分析了MAWA机制的可靠性与高效性。     

通用可组合安全的可信网络接入与认证协议

可信计算组织提出的可信网络连接框架规范无法安全高效地支持未来移动计算和普适计算等应用场景,针对该问题,在完整性验证中采用服务器和客户端的双向认证方法,提出一种可信网络接入与认证协议,提高通信安全性和可靠性。在身份认证时采用对称密钥算法,减少服务器和客户端的加解密运算时间,提高通信效率。使用安全等级较高的通用可组合安全框架对协议进行分析,结果表明该协议达到通用可组合安全等级。     

基于Android 云计算的移动点餐系统

系统发挥Android富有创造力和想象力的"云"应用开发,实现一套Android客户端软件和完善的后台服务功能来完成点餐功能。该系统主要包括后台数据库服务器、WEB服务器、无线网络、Android前端等部分。客户端Android系统智能手机具有前端处理与计算能力,而且通过无线网络访问WEB服务器,如果需要数据访问,则访问后台数据库。介绍了系统架构的设计与搭建、技术选型、后台数据库的设计与实现、基本实用的点餐功能的分析、设计与开发。     

Mobile collaborative medical display system

Because of recent advances in wireless communication technologies, the world of mobile computing is flourishing with a variety of applications. In this study, we present an integrated architecture for a personal digital assistant (PDA)-based mobile medical display system that supports collaborative work between remote users. We aim to develop a system that enables users in different regions to share a working environment for collaborative visualization with the potential for exploring huge medical datasets. Our system consists of three major components: mobile client, gateway, and parallel rendering server. The mobile client serves as a front end and enables users to choose the visualization and control parameters interactively and cooperatively. The gateway handles requests and responses between mobile clients and the rendering server for efficient communication. Through the gateway, it is possible to share working environments between users, allowing them to work together in computer supported cooperative work (CSCW) mode. Finally, the parallel rendering server is responsible for performing heavy visualization tasks. Our experience indicates that some features currently available to our mobile clients for collaborative scientific visualization are limited due to the poor performance of mobile devices and the low bandwidth of wireless connections. However, as mobile devices and wireless network systems are experiencing considerable elevation in their capabilities, we believe that our methodology will be utilized effectively in building quite responsive, useful mobile collaborative medical systems in the very near future.     

Android智能手机的云服务应用研究

云计算的应用目标并不仅局限于PC,随着移动互联网的蓬勃发展,基于手机等移动终端的云服务已成为IT行业炙手可热的新业务发展模式。本文基于Openmobster搭建移动云计算环境,并利用Android智能手机作为终端来访问云端服务器资源,以数据传输的事务处理为应用背景,采用c／s模式和B／S模式相结合的方式,建立了云服务下移动智能终端信息采集和处理的基础架构,并根据此架构初步实现了追踪定位的功能。该方法通过无线网络连接,利用服务器端与手机客户端的即时通信,实现了为Android智能手机提供云推送和云同步的服务。     

TIBM：一种基于瘦客户机计算的无线浏览器模型

提出了一种基于瘦客户机计算模式的无线浏览器模型,利用显示逻辑与处理过程分离的机制,使得浏览器客户端能够获得服务器计算能力的支援,以降低客户端负载。为控制网络流量,研究了模型中的计算任务划分策略,采用了半集中计算的模式,使网页在客户端渲染,实现了一个基于该模型的无线浏览器系统原型。实验结果表明,该模型能够同时降低客户端计算负载和网络传输负载,减少页面内延时,可提供无缝的网络浏览体验。     

A mobile knowledge carrier with personalized knowledge provision

In the e-commerce era, the organization knowledge within a centralized knowledge management server can be easily accessed over the Internet by the client PCs at distinct locations. Currently, the personal digital assistant (PDA) has been widely used as the carrier for personal memos and daily records for its high mobility. Taking advantage of the personal information, the user requirements for knowledge can be determined. This research presents an intelligent KM scheme by integrating the PDA information (including notes, schedules and address book) mining model and mobile knowledge management mechanism. Based on the user profile mining technique, the PDA-ready knowledge that fits user requirements can be imported from the knowledge server to the client PDA. Demonstration cases are also provided to illustrate the applications of the proposed model in the content services and healthcare industry. By application of the mobile KM technique, the organization knowledge can be seamlessly provided to the PDA user via the data synchronization process. The attempt of this paper is to present an applicable and intelligent mobile knowledge carrier for realization of the mobile office.     

Distributed computing paradigms for collaborative signal and information processing in sensor networks

In this paper, we report the development of an energy-efficient, high-performance distributed computing paradigm to carry out Collaborative Signal and Information Processing (CSIP) in sensor networks using mobile agents. In this paradigm, the processing code is moved to the sensor nodes through mobile agents, in contrast to the client/server-based computing, where local data are transferred to a processing center. Although the client/server paradigm has been widely used in distributed computing, the many advantages of the mobile agent paradigm make it more suitable for sensor networks. The paper first presents simulation models for both the client/server paradigm and the mobile agent paradigm. We use the execution time, energy and energy*delay as metrics to measure the performance. Several experiments are designed to show the effect of different parameters on the performance of the paradigms. Experimental results show that the mobile agent paradigm performs much better when the number of nodes is large while the client/server paradigm is advantageous when the number of nodes is small. Based on this observation, we then propose a cluster-based hybrid computing paradigm to combine the advantages of these two paradigms. There are two schemes in this paradigm and simulation results show that there is always one scheme which performs better than either the client/server or the mobile agent paradigms. Thus, the cluster-based hybrid computing provides an energy-efficient and high-performance solution to CSIP.     

面向富互联网应用的计算任务动态迁移机制

富互联网应用(rich Internet application,RIA)目前已经成为重要的应用模式.随着信息技术日益泛在化和服务化,富互联网应用也开始在移动设备之上运行.然而,由于设备计算能力的不足,很可能出现部分代码无法在富客户端顺利运行的情况.提出面向富互联网应用的计算任务动态迁移机制,在应用运行过程中,动态地将...