油气工程师助手（PDA）移动代理平台的研究与实现

移动计算被认为是对未来最有影响的四大技术方向之一,它使得计算机或其他信息设备在没有与固定的物理连接设备相连的情况下能够传输数据,将有用、准确、及时的信息能提供给在任何时间、任何地点需要它的任何用户.而移动代理是唯一能满足移动计算全部要求的体系框架.为了更好地支持便携式设备上Microsoft的WinCE平台的移动计算,设计了一个基于C 的支持Windows操作系统的企业用移动代理系统--WinMAS,首次提出了基于编译性语言上的新移动代理迁移机制--利用RPC的序列化和远线程插入机制.     

基于移动计算的移动代理平台的实际应用

移动计算被认为是对未来最有影响的四大技术方向之一。它的作用在于将有用、准确、及时的信息与中央信息系统相互作用,分担中央信息系统的计算压力,使这些信息能提供给在任何时间、任何地点需要它的任何用户。为了更好的支持便携式设备上Microsoft的WinCE平台的移动计算,本文通过对基于Java的移动代理系统Aglet的比较,介绍了基于Windows平台的移动代理系统——WinMAS的优越性,同时详细地给出了相关的应用示例。     

移动计算最新杀手锏——手机移动定位技术

移动计算技术指将有用、准确、及时的信息提供给在任何时间、任何地点需要它的任何客户。人们将通过具有移动计算功能的移动计算机、汽车、手机甚至是手表等新一代的智能化设备,随时随地利用移动数据连接所需的信息系统,获取所需的信息。人类需要的最基本信息是时间、地点和内容。而在人们的移动中,最需要的信息就是"位置信息",特别是出现紧急情况时更需要"确切的位置信息"。目前在发展中的移动计算中最热门的领域便是——定位服务技术。     

数据挖掘与代理技术在入侵检测中的应用研究

移动代理技术提供了一个新的计算方式,即程序以软件代理的形式出现,它能在一台主机上停止对它的执行,通过移动到第一台主机上恢复执行。数据挖掘技术是从大型的数据库或数据仓库中提取隐含的有潜在价值的信息或模式的一种有效方法。文中在深入研究入侵检测与移动代理技术的基础上,提出了一种基于移动代理的入侵检测系统模型,并对数据挖掘技术在系统中的应用作了详细分析和具体实现。     

数据挖掘与代理技术在入侵检测中的应用研究

移动代理技术提供了一个新的计算方式,即程序以软件代理的形式出现,它能在一台主机上停止对它的执行,通过移动到第一台主机上恢复执行.数据挖掘技术是从大型的数据库或数据仓库中提取隐含的有潜在价值的信息或模式的一种有效方法.文中在深入研究入侵检测与移动代理技术的基础上,提出了一种基于移动代理的入侵检测系统模型,并对数据挖掘技术在系统中的应用作了详细分析和具体实现.     

支持移动设备接入Gnutella网络的代理架构研究

针对当前移动设备无法加入Gnutella网络实现文件共享网络的现状,提出一种移动代理Gnutella网络架构的设计方案。利用移动代理作为移动设备的代理加入Gnutella网络,帮助移动设备实现文件的共享功能。架构能有效地减少移动设备的信息流量,并支持移动设备在Gnutella网络中实现可移动性。     

基于Linux的移动IP家乡代理的研究与实现

移动IP是-个用来支持节点移动性的因特网协议.它的设计目标是使节点无论在什么位置都可以无缝地接入因特网,并且可以不用改变节点原来的IP地址.文中的主要工作是实现移动IP中定义的一个功能实体--家乡代理.在原有的路由协议基础之上通过修改家乡代理的IP层处理机制,使其具有移动代理的功能.这样做的好处在于可以不必对现有的设备作任何硬件和软件的更新就可以将其它节点发给移动节点的数据包转发到它现在所处的位置.     

普适环境下基于软件代理虚拟化的应用迁移

虚拟计算环境中的用户在物理空间的移动要求其相关应用能够在网络空间进行相应的移动.为支持应用的迁移,利用软件代理技术来实现计算网络空间以及其中资源的虚拟化.具体而言,就是结合情境感知技术,利用软件代理本身所具有的自治性和移动性实现应用组件的动态绑定和迁移,进而提出一种基于代理的支持应用迁移的结构模型MDAgent,并实现了相应的原型系统,可为应用的迁移提供移动管理、情境感知、资源匹配和推理机制等多方面的支持.在此基础上开发出若干应用并给出相关性能分析.     

移动通信的新亮点--手机定位服务

现在任何人只要拥有一部手机就可以随时随地地实现人与人之间的语音交流和数字信息交互。目前我国的移动通信正在由第二代向第三代过渡,第三代将完全过渡到数字数据通信和分组业务上来,由此推动了移动计算技术在手机应用方面的飞速发展。移动计算技术是指将有用、准确、及时的信息提供给在任何时间、任何地点需要它的任何客户。人们将通过具有移动计算功能的移动计算机、汽车、手机甚至手表等新一代的智能化设备,随时随地利用移动数据连接所需的信息系统获取所需的信息,这将大大改变人们的生活方式和工作方式。     

分布式移动代理系统的异步死锁检测

移动代理技术在为分布式应用提供全新的网络计算方式的同时也产生了传统分布式计算领域所没有的新的交互模式和执行模式。传统分布式计算的处理方法如并发控制和死锁检测方法不再适用于客户和服务提供者都可在网络中随处移动的移动代理系统。通过移动代理来建模长寿事务,并根据移动代理的特点提出了一种异步分布式死锁检测和解除算法。它将事务代理的执行与死锁检测机制分离,用专门的代理负责死锁检测的初始化、检测和消除等工作。死锁的检测通过创建若干检测代理,使其在各个站点间移动来收集资源请求和分配信息,并据此构造全局等待图;通过分析和探测全局等待图中是否存在圈来完成。算法具有独立于网络的拓扑结构,死锁的检测和事务代理的执行异步操作,不对代理的移动性施加任何限制等特点。     

一种移动agent结构化迁移机制的设计和实现

移动agent计算模式将成为未来网络计算的主流模式.移动agent的迁移机制是其技术核心之一.该文分析了现有移动agent系统中采用的几种代表性迁移技术,提出了一种新的结构化迁移机制.该机制的主要特点如下:(1) agent的旅行计划和功能体完全分离;(2) 旅行计划本身也具有严格定义的结构;(3) 提供了3种灵活有力的迁移模式.因此,它能有效地控制移动agent的复杂度,有利于agent的复用.在该机制的基础上,设计并实现了移动agent系统Mogent1.0.     

Mogent系统迁移机制的设计和实现

移动agent计算模式将成为未来网络计算的主流模式,迁移技术 是移动agent的核心技术之一,受到了广泛的关注,在分析现有agent系统迁移机制的基础上,提出一种结构化的agent迁移机制,该机制提供了任务级迁移,采用结构化旅行计划三月分离移动信息和agent功能体,在降低agent开发复杂度的同时保证了较高的灵活性和表达能力,最后,结合自笔研制的移动agent系统-Mogent系统,讨论了该机制的实现工作。     

Mobile agents in wireless devices

The networks that connect handheld wireless devices such as cell phones and PDAs suffer from low bandwidth and a high incidence of network errors. By employing mobile agents, such devices could provide a reliable technology for message transport over wireless links. Mobile agents are inherently distributed software entities that reduce the load on the network when they move. Mobile agents can be employed in wireless handheld devices in two ways: An agent platform could be installed on the device, enabling mobile agents to run directly on it, or devices could access and use remote mobile agents running on wired networks. Each approach is viable and has its own advantages and domain-specific applications. Some high-end devices would benefit from running a mobile agent platform that lets agents run locally, but this would not be beneficial to others because of processing power and memory constraints or for security reasons.     

MAP: Design and implementation of a mobile agents' platform

The recent development of telecommunication networks has contributed to the success of applications such as information retrieval and electronic commerce, as well as all the services that take advantage of communication in distributed systems. In this area, the emerging technology of mobile agents aroused considerable interest. Mobile agents are applications that can move through the network for carrying out a given task on behalf of the user. In this work we present a platform called MAP (Mobile Agents Platform) for the development and the management of mobile agents. The language used both for developing the platform and for carrying out the agents is Java. The platform gives the user all the basic tools needed for creating some applications based on the use of agents. It enables us to create, run, suspend, resume, deactivate, reactivate local agents, to stop their execution, to make them communicate each other and migrate.     

AGENT TCL: targeting the needs of mobile computers

Mobile computers have become increasingly popular as users discover the benefits of having their electronic work available at all times. Using Internet resources from a mobile platform, however, is a major challenge. Mobile computers do not have a permanent network connection and are often disconnected for long periods. When the computer is connected, the connection is often prone to sudden failure, such as when a physical obstruction blocks the signal from a cellular modem. In addition, the network connection often performs poorly and can vary dramatically from one session to the next, since the computer might use different transmission channels at different locations. Finally, depending on the transmission channel, the computer might be assigned a different network address each time it reconnects. Mobile agents are one way to handle these unforgiving network conditions. A mobile agent is an autonomous program that can move from machine to machine in a heterogeneous network under its own control. It can suspend its execution at any point, transport itself to a new machine, and resume execution on the new machine from the point at which it left off. Agent Tcl is a mobile agent system whose agents can be written in Tcl, Java, and Scheme. Agent Tcl has extensive navigation and communication services, security mechanisms, and debugging and tracking tools. We focus on Agent Tcl's architecture and security mechanisms, its RPC system, and its docking system, which lets an agent move transparently among mobile computers, regardless of when they are connected to the network     

A secure migration process for mobile agents

This article describes a decentralized secure migration process of mobile agents between Mobile‐C agencies. Mobile‐C is an IEEE Foundation for Intelligent Physical Agents (FIPA) standard compliant multi‐agent platform for supporting C/C++ mobile and stationary agents. Mobile‐C is specially designed for mechatronic and factory automation systems where malicious agents may cause physical damage to machinery and personnel. As a mobile agent migrates from one agency to another in an open network, the security concern of mobile agent systems should not be neglected. Security breaches can be minimized considerably if an agency only accepts mobile agents from agencies known and trusted by the system administrator. In Mobile‐C, a strong authentication process is used by sender and receiver agencies to authenticate each other before agent migration. The security framework also aims to guarantee the integrity and confidentiality of the mobile agent while it is in transit. This assures that all agents within an agency framework were introduced to that framework under the supervision and permission of a trusted administrator. The Mobile‐C Security protocol is inspired from the Secure Shell (SSH) protocol, which avoids a single point of failure since it does not rely on a singular remote third party for the security process. In this protocol, both agencies must authenticate each other using public key authentication, before a secure migration process. After successful authentication, an encrypted mobile agent is transferred and its integrity is verified by the receiver agency. This article describes the Mobile‐C secure migration process and presents a comparison study with the SSH protocol. The performance analysis of the secure migration process is performed by comparing the turnaround time of mobile agent with and without security options in a homogeneous environment. Copyright © 2010 John Wiley & Sons, Ltd.     

移动代理人编程技术与移动用戶管理系统探讨

有自我控制与辨别身份能力的移动代理人编程技术,不但能够在网路上移动,也能够与其他代理人编程沟通及执行任务.由于移动代理人常常运作于异质的网路或作业系统(operating system)环境下,因此,一个具有整体逻辑性操作界面来存取实体结构的管理系统就显得越发重要.提出了一个能够追踪和维持移动代理人的管理系统,并且应用于远距教学(distance learning).此系统的主要目的在于提供移动代理人通用的存取环境.为了能使此系统完全运作,论述了移动代理人通信网路模组、移动代理人演化阶段来支援管理代理人与用户端代理人.另外,也将移动代理人所使用的工具编程整合成为角色扮演(role-setting)物件;此角色扮演物件是符合所谓应用编程驱使元件(application-driven component)的,因此,此系统也能够符合专业化利益的使用者的需求.     

The JavaSeal Mobile Agent Kernel

Mobile agents show promise as a new distributed programming paradigm in which locality plays a central role—programs that are able to move closer to their data can overcome limitations of connectivity, latency or bandwidth. Mobility also enables distributed systems to evolve; for instance, the deployment of a new service over a network can be programmed as part of the service itself. Of course, moving programs introduces new challenges. One of these is related to program structure: How much of a computation should be moved? Where are the boundaries between mobile and immobile entities drawn? A second challenge is to provide security guarantees: How can the actions of mobile agent be controlled? And what kinds of security properties can we realistically expect to enforce? We answer these questions within the framework of the JavaSeal mobile agent system kernel. JavaSeal provides several abstractions for constructing agent systems in Java. Our basic building block is the seal which is a nested encapsulated computation fragment with sharply delineated boundaries. Strands are sequential threads of computation bound to a seal. Capsules transfer passive seals and objects over communication channels; Traffic over channels is regulated by portals. We argue that these abstractions are sufficient to program secure mobile agent systems. An electronic commerce application built over our kernel is used as a demonstrator.

     

移动Agent的一种支持安全与容错的迁移机制

移动Agent计算模式将成为未来网络计算的主流模式。移动Agent的迁移机制是其技术核心之一,受到了广泛的关注。为了提高移动Agent迁移的可靠性和安全性,提出一种支持安全与容错的迁移机制。该机制利用结构化迁移机制寻址,并引入分布式事务、可靠认证与加密等机制,使得移动Agent在迁移过程中能有效保护主机与移动Agent的安全性,并提供容错支持。