基于普适计算的分布式定位设计

普适环境中,定位计算是上下文察觉计算的重要内容。本文提出分布式定位计算的思想,该思想摆脱了以往传统定位中先确定用户坐标再判断其所处区域的繁琐模式,将对用户所处区域的计算分散至底层的感知设备中,减轻了计算设备的计算负担,提高了上下文感知系统的效率,并通过实现该定位设计验证了分布式定位设计的可行性。     

Centaurus: An Infrastructure for Service Management in Ubiquitous Computing Environments

In the near future, we will see dramatic changes in computing and networking hardware. A large number of devices (e.g., phones, PDAs, even small household appliances) will become computationally enabled. Micro/nano sensors will be widely embedded in most engineered artifacts, from the clothes we wear to the roads we drive on. All of these devices will be (wirelessly) networked using Bluetooth, IEEE 802.15 or IEEE 802.11 for short range connectivity creating pervasive environments. In this age where a large number of wirelessly networked appliances and devices are becoming commonplace, there is a necessity for providing a standard interface to them that is easily accessible by any user. This paper outlines the design of Centaurus, an infrastructure for presenting services to heterogeneous mobile clients in a physical space via some short range wireless links. The infrastructure is communication medium independent; we have implemented the system over Bluetooth, CDPD and Infrared, three well-known wireless technologies. All the components in our model use a language based on Extensible Markup Language (XML) for communication, giving the system a uniform and easily adaptable interface. Centaurus defines a uniform infrastructure for heterogeneous services, both hardware and software, to be made available to diverse mobile users within a confined space.     

Piecewise Network Awareness Service for Wireless/Mobile Pervasive Computing

This paper presents a piecewise framework for network awareness service (NAS) for wireless/mobile pervasive computing. We investigate how piecewise consideration of wired and wireless elements of the framework architecture benefits service advertisement and discovery and network-awareness techniques. We also discuss scalability of the NAS framework with respect to platform computing capabilities. The framework is suitable for a wide range of computing devices, from powerful ones with multi-tasking operating systems (OS) to small ones with lightweight OS. Case studies applying the NAS framework to sensor monitoring in home networks and data streaming in pervasive multimedia computing are presented. The analytical results on the performance of the NAS framework in these case studies show that it has significant advantages over traditional network-awareness frameworks in terms of reducing wireless bandwidth consumption and saving battery energy of mobile devices.     

普适服务综述

随着技术和市场的发展,电信网和互联网正在走向融合,形成一体化网络,提供的服务也将逐步趋同。普适服务融合了各方面对未来服务的需求和期望,成为超3G、下一代网络（NGN）、下二代互联网（NGI）等研究领域的热点问题。普适服务的概念起源于普适计算和超3G领域,其特征包括普适性、移动性、透明性、质量可控性、个性化、自适应性、主动性、安全性、易用性、多样性、快捷性。3GPP、OMA等标准化组织以及欧盟的超3G研究项目都针对普适服务的不同特征进行了研究。当前普适服务的研究热点包括上下文感知、业务使能等技术。     

面向普适计算的动态多级安全访问控制方案

提出一种面向普适计算的动态多级安全访问控制新方案,形式化描述了访问控制的构成要素,定义了动态访问控制策略,最后给出了授权实现算法.方案既保证了授权的动态性,又增强了访问控制的安全性,更适合于普适计算环境.     

分布式计算技术概述

分布式计算已经广泛而又深入的参透到各行各业的科技应用中.本文对几种主要的分布式计算技术,如网格、云计算、普适计算等,做了分析和比较,同时对分布式计算目前所面临的问题做了总结.最后对分布式计算技术未来的发展方向做了展望与预测.     

普适计算中多通道交互框架的研究

多通道交互是普适计算人机交互中一个新的发展趋势,国际标准化组织W3C公布的多通道交互协议旨在开发支持普适计算设备多通道交互的通用协议标准。本文对此标准协议中的多通道交互基本框架进行了分析,并提出了此框架中,环境上下文在交互管理构件和系统环境构件中与用户输入输出信息的融合框架。在此框架基础上对驾驶导航(Driving Direction)实例进行分析。     

Service Discovery in Agent-Based Pervasive Computing Environments

Directory based service discovery mechanisms are unsuitable for ad-hoc m-commerce environments. Working towards finding an alternate mechanism, we developed Allia: a peer-to-peer caching based and policy-driven agent-service discovery framework that facilitates cross-platform service discovery in ad-hoc environments. Our approach achieves a high degree of flexibility in adapting itself to changes in ad-hoc environments and is devoid of common problems associated with structured compound formation in mobile commerce environments. Device capabilities and limitations, user preferences regarding device usage, application specifics with respect to mobile commerce are factors that our framework adapts to. We have described our initial implementation of Allia over ThinkPads and iPAQs by extending the LEAP Agent Platform and using Bluetooth as the underlying network protocol. In addition, we evaluated Allia's performance by running simulations of our protocol in Glomosim simulator. We also compared our framework against a structured compound-based architecture.     

安全桌面云计算架构解决方案

当前,很多企业和行业用户纷纷采用桌面云计算技术改造或建设自身的信息化基础设施,以期提高信息系统治理水平,减少信息外泄的途径。随着虚拟化等关键技术的引入,桌面云计算架构也面临着新的安全风险,针对桌面云计算架构所面临的安全风险提出了较为完整的解决方案,远程用户可以基于此随时随地利用有线/无线等多种网络接入方式访问后台数据中心,如同在本地一样操作各类业务。     

Supporting Service Discovery,Querying and Interaction in Ubiquitous Computing Environments

In this paper, we contend that ubiquitous computing environments will be highly heterogeneous, service rich domains. Moreover, future applications will consequently be required to interact with multiple, specialised service location and interaction protocols simultaneously. We argue that existing service discovery techniques do not provide sufficient support to address the challenges of building applications targeted to these emerging environments.This paper makes a number of contributions. Firstly, using a set of short ubiquitous computing scenarios we identify several key limitations of existing service discovery approaches that reduce their ability to support ubiquitous computing applications. Secondly, we present a detailed analysis of requirements for providing effective support in this domain. Thirdly, we provide the design of a simple extensible meta-service discovery architecture that uses database techniques to unify service discovery protocols and addresses several of our key requirements. Lastly, we examine the lessons learnt through the development of a prototype implementation of our architecture.     

基于XML实现液晶编程的一种新方法

针对传统液晶显示编程工作量大、繁琐，且程序形成后，再进行修改比较困难的缺点，提出了基于可扩展标志语言(Extensible Markup Language，XML)技术编程的一种新方法。这种方法把显示内容和显示算法分开，由Pc绘制显示内容并转换成基于XML标准的文件存储到单片机的ROM中，而显示算法只需根据显示文件的格式进行判断调用相应的函数。这种运用XML技术实现液晶显示编程，不仅提高编程的效率、增强程序的可维护性，而且大大减小程序占用的空间。     

基于抽象状态机的普适服务组合分析与验证

提出了一个普适环境下服务组合的框架,使用抽象状态机对服务的行为进行不同精化层级的形式化描述,然后利用 CoreASM 这一模型检测工具对服务组合进行模拟执行验证,从而验证服务组合的正确性.最后给出了一个运用此方法进行服务组合验证的典型应用场景.     

基于网格的科学计算的公平服务方法研究

在科学与工程计算领域，各种科学计算库及其工具软件扮演着十分重要的角色。在科学计算网格中．通过引入软件代理可以更好地利用这些计算库和工具软件库。本文通过对网络化科学计算工具NetSolve的分析．通过引入服务队列、访问率、时差和连续性等因子，改进了其中的用户访问策略和资源调度方法，使其具有资源访问的公正性和负载均衡性。     

分布式系统中的安全访问控制

本文主要讨论如何利用现代密码技术实现分布式系统中的安全访问控制。     

云计算时代的开放安全服务体系分析

针对移动互联网时代日益发展带来的安全性问题,在既要满足服务的多样性,又要满足服务安全性的双重使命下,如何构建移动互联网云计算时代开放安全的云服务,文中提出了一种开放的安全服务体系。同时,基于开发安全服务体系的各种技术特征,设计并构建了一个云服务平台架构,可以提供能力开放应用云、企业安全私有应用云和认证鉴权公共应用云。     

A Semantic Service Discovery Network for Large‐Scale Ubiquitous Computing Environments

This paper presents an efficient semantic service discovery scheme called UbiSearch for a large‐scale ubiquitous computing environment. A semantic service discovery network in the semantic vector space is proposed where services that are semantically close to each other are mapped to nearby positions so that the similar services are registered in a cluster of resolvers. Using this mapping technique, the search space for a query is efficiently confined within a minimized cluster region while maintaining high accuracy in comparison to the centralized scheme. The proposed semantic service discovery network provides a number of novel features to evenly distribute service indexes to the resolvers and reduce the number of resolvers to visit. Our simulation study shows that UbiSearch provides good semantic searchability as compared to the centralized indexing system. At the same time, it supports scalable semantic queries with low communication overhead, balanced load distribution among resolvers for service registration and query processing, and personalized semantic matching.     

Study on the Distributed Routing Algorithm and Its Security for Peer-to-Peer Computing

By virtue of its great efficiency and graceful architecture, the Client/Server model has been prevalent for more than twenty years, but some disadvantages are also recognized. It is not so suitable for the next generation Internet (NGI), which will provide a high-speed communication platform. Especially, the service bottleneck of Client/Server model will become more and more severe in such high-speed networking environment. Some approaches have been proposed to solve such kind of disadvantages. Among these, distributed computing is considered an important candidate for Client/Server model.     

浅谈云计算及其应用

云计算是当前信息领域的又一个热点,但是,大部分人对它还不是非常了解,甚至还存在着一些误解。本文将阐述云计算的概念,并将其和容易与之相混淆的网格计算作比较,分析它们各自的相关特点,以使更多的人对云计算有所了解。同时阐述了云计算的优势、现状及其应用,并对云计算的发展及面临的挑战进行了分析。云计算最终将改变人们获取信息、分享内容和互相沟通的方式。     

Blockchain Meets Generative Behavior Steganography:A Novel Covert Communication Framework for Secure IoT Edge Computing

The rapid development of Internet of things(IoT)and edge computing technologies has brought forth numerous possibilities for the intelligent and digital future.The frequent communication and interaction between devices inevitably generate a large amount of sensitive information.Deploying a blockchain network to store sensitive data is crucial for ensuring privacy and security.The openness and synchronicity of blockchain networks give rise to challenges such as transaction privacy and storage capacity issues,significantly impeding their development in the context of edge computing and IoT.This paper proposes a reliable fog computing service solution based on a blockchain fog architecture.This paper stores data files in the inter planetary file system(IPFS)and encrypts the file hash values used for retrieving data files with stream cipher encryption.It employs a steganographic transmission technique leveraging AlphaZero's Gomoku algorithm to discretely transmit the stream cipher key across the block-chain network without a carrier,thus achieving dual encryption.This approach aims to mitigate the storage burden on the blockchain network while ensuring the security of transaction data.Experimental results demonstrate that the model enhances the transmission capacity of confidential information from kilobytes(KB)to megabytes(MB)and exhibits high levels of covert and security features.