移动Agent系统的主动通信机制

解决由Agent移动产生的可靠性通信问题.在分析已有方法的基础上,提出一种保证移动Agent之间可靠、高效通信的"主动通信"机制,并给出它的可靠性分析和通信效率分析.它能够在通信双方自由移动的情况下,将消息可靠、高效地从发送方提交给接收方,并承诺消息传递的exactly-once语义,为Agent通信语言等高层通信方式奠定了可靠的基础.     

基于信息表的移动Agent通信机制

通信是移动Agent必不可少的组成部分.许多研究者针对这一问题进行了深入的研究,并提出了一些移动Agent的通信机制,但是现有的这些通信机制在解决通信失效和消息追逐上都存在着一定的不足.针对这些问题,通过将信息表引入移动Agent的通信机制中,提出一种基于信息表的移动Agent通信机制.在这种通信机制中,把移动Agent要接收的消息按照其特性分为主动消息和被动消息,利用动态改变路标中信息表参数的方法来解决移动Agent之间通信所面临的难题.     

一个新的移动Agent的可靠通信算法

移动Agent技术是近年来分布式计算领域中一项新兴的技术。其中有很多领域的研究尚不成熟，如Agent的可靠通信。Agent的可靠通信一直是Agent技术的一个难题，在现有的很多Agent系统中都未得到解决。比较了几种移动Agent可靠通信的算法，并提出了一种新的移动Agent的可靠通信算法。     

一种改进的移动Agent通信机制研究

通过对现有移动Agent通信机制的分析,将移动Agent名字解析机制与消息传递机制相结合,提出一种高效可靠的移动Agent通信模型.利用域名服务器(domain server)和移动Agent系统的通信部件(communicator)相结合来实现移动Agent通信.采用全局命名方式ADHN,以解决透明寻址问题.对于消息处理,则使用基于邮箱的消息缓存和转发机制,移动Agent状态、消息超时和优先级的引入很好地解决通信失效问题,提高了通信效率.     

一种基于绑定邮箱的可靠移动Agent通信算法

移动Agent通信算法一直是近些年研究的重点.通过分析几种移动Agent通信机制,并且在总结前人研究的基础上,提出了一种可靠、安全、灵活和消息利用率最优的邮箱绑定Agent通信算法.     

一种入侵检测系统的分布式多Agent通信机制

在基于Agent的分布式入侵检测系统中,多Agent之间的通信是一个关键的问题。文章给出了入侵检测系统的分布式多Agent通信机制,即基于双向指针的移动多Agent通信方法,实现了多Agent之间尤其是移动多Agent之间可靠通信,克服了集中式通信机制的通信瓶颈问题,还具有较好的容错性和扩展性。     

一种改进的移动Agent通信算法

Agent移动的可靠性、实时性是移动Agent通信中的热点。在总结了前人算法的基础上,改进并实现了一个基于多邮箱的高效可靠的移动Agent通信算法。既保证了通信的可靠性和实时性,又使得移动Agent的迁移变得简单和自由。     

基于移动代理入侵检测系统中的通信机制研究

移动Agent已广泛应用于入侵检测系统之中,Agent通信的可靠性、实时性是其关键。本文在分析现有的基于移动代理通信机制的基础上,将通讯录机制和多邮箱机制相结合,实现了一个可靠的移动Agent通信机删,能解决Agent通信过程中出现的通信失效和消息追逐的问题．并能使Agent迁移不受限制。     

移动Agent位置透明通信模型的设计

提出一种高效可靠的移动Agent通信模型――D-C通信模型,结合域名字解析器和移动Agent系统中的Communicator实现移动Agent之间的通信。通过引入一种基于全局的、与位置无关的命名方法――通用Agent标识,论述移动Agent的创建、迁移和访问及消息的发送和处理。     

基于移动Agent的分布式仿真节点间通信机制的研究

本文引入了各类功能各异的移动Agent,提出了一个能够保证移动Agent之间可靠、高效地进行通信的面向消息的主动通信机制,在基于Agent的分布式仿真体系平台上,实现了一个网络性能管理系统。     

A scalable group communication mechanism for mobile agents

Many multi-agent applications based on mobile agents require message propagation among group of agents. A fast and scalable group communication mechanism can considerably improve performance of these applications. Unfortunately, most of the existing approaches do not scale well and disseminate messages slowly when the number of agents grows.In this paper, we propose Sama, a new group communication mechanism, to speed up message delivery for a group of mobile agents on a heterogeneous internetwork. The main contribution of Sama is distribution and parallelization of message propagation in an efficient way to achieve scalability and high-speed of message delivery to group members. Sama uses message dispatcher objects (MDOs), which are stationary agents on each host, to propagate messages concurrently. The proposed mechanism is independent of agent locations and transparently delivers messages to the group using constant number of remote messages. It also transparently recovers from host failures. We also present a Hop-Ring protocol that considerably improves the performance of message dissemination in Sama. Our experimental results show that message propagation in Sama is significantly fast compared to the previously proposed methods.     

Architecture for mobile group communication in campus environment

The demand for group communication using smart devices in campus environment is increasing rapidly. In this paper, we design an architecture for a mobile group communication system (MGCS) on campus by using Wi-Fi networks and smart devices. The architecture is composed of a web-based system and a smart device based mobile system. Through the systems, users on campus create community/mobile group, maintain dynamic group membership, and reliably deliver the message to other users. We use the common features of many smart devices to develop a prototype that works on off-the-shelf hardware. In the experimental section, we demonstrate our system using various real scenarios which can occur in university campuses.     

移动社交网络实时通信机制的研究

实时通信技术在移动互联网的应用已得到广泛的认可,关系较为紧密的用户需要进行实时性更强的富媒体通信,这要求在网络连接并不稳定的移动互联网环境,提供相对可靠的实时通信机制．本文将使用ELGG社交网络平台,采用MQTT作为消息传输协议,利用手机广播用户已有的社交关系,设计实现了基于消息通知的实时通信机制体系结构,并且通过手机终端信息的交互验证了这种通信方式的可行性．     

Reliable Communication for Highly Mobile Agents

The provision of a reliable communication infrastructure for mobile agents is still an open research issue. The challenge to reliability we address in this work does not come from the possibility of faults, but rather from the mere presence of mobility, which complicates the problem of ensuring the delivery of information even in a fault-free network. For instance, the asynchronous nature of message passing and agent migration may cause situations where messages forever chase a mobile agent that moves frequently from one host to another. Current solutions rely on conventional technologies that either do not provide a solution for the aforementioned problem, because they were not designed with mobility in mind, or enforce continuous connectivity with the message source, which in many cases defeats the very purpose of using mobile agents.In this paper, we propose an algorithm that guarantees delivery to highly mobile agents using a technique similar to a distributed snapshot. A number of enhancements to this basic idea are discussed, which limit the scope of message delivery by allowing dynamic creation of the connectivity graph. Notably, the very structure of our algorithm makes it amenable not only to guarantee message delivery to a specific mobile agent, but also to provide multicast communication to a group of agents, which constitutes another open problem in research on mobile agents. After presenting our algorithm and its properties, we discuss its implementability by analyzing the requirements on the underlying mobile agent platform, and argue about its applicability.     

基于移动平台的火灾短信报警系统的设计与实现

随着无线通信技术的发展和手机的普及,短信的使用给人们的工作和生活带来了诸多的便利.基于移动平台的火灾短信报警系统实现了火灾报警短信的群发,保证准确、及时的把火灾信息发送给企业的有关人员,便于相关部门及时采取消防措施.该系统利用全球移动通讯短消息服务,以微型机、全球移动通讯模块作为硬件基础,以VC .NET为开发环境,通过向计算机串口发送AT命令操作全球移动通讯模块实现了火灾短信报警的功能.     

Total ordering group communication protocol based on coordinating sequencers for multiple overlapping groups

This paper presents a total ordering protocol for group communication systems with multiple overlapping groups. Our protocol takes advantages of the simplicity of the sequencer-based approach, but employs multiple sequencers to achieve better load balance. For a given message, the sequencer of the destination group constructs a sequencing array by requesting for relative delivery positions from the sequencers of the overlapping groups. The sequencing array is used by any receiving process to determine the delivery sequence of the message. The notion of logical clock is used for determining the relative delivery sequences of the messages. The coordination between the sequencers is performed in a simple, asynchronous and non-blocking manner. The delivery operation at a receiving process is very simple, and a message can be delivered as soon as it becomes deliverable. These factors amount to a significant saving of the computing and communication overhead for the system. As the protocol demands the minimum effort from the group members it is suitable for mobile computing environment in which mobile devices are typically tight on resources. In the paper, we also present some ways to enhance the performance of the system. Extension of the protocol to encompass the preservation of causality, the dynamic group membership and the failure recovery is included in the paper.     

一种面向移动计算的低代价透明检查点恢复协议

移动计算系统中的检查点恢复协议面临着许多与传统分布式系统所不同的问题.在目前已出现的支持移动计算的检查点恢复机制中,基于建立全局一致的检查点的方法不能确保错误的独立恢复;基于m-MSS-m通信的消息日志方法其移动站之间交换的消息需通过移动基站的转发.提出了一种基于消息日志的支持移动站之间直接通信(m-m)的容错协议并给出了相应的算法及正确性证明.与m-MSS-m通信相比,m-m通信有利于降低信道冲突;减少消息传递延迟.仿真结果表明,所设计的协议比传统协议具有更小的无错误状态下引入负载和错误恢复时间.     

移动PC环境下自动短信与邮件系统的设计

为解决移动PC环境下的远程通信问题,设计了一个自动短信收发与邮件发送系统.该系统基于GPRS无线通信网,利用串行通信和网络技术,采用手机通信的AT指令和VB 6.0提供的MSComm控件等,实现了对短消息的自动收发;使用Winsock套接字技术,解决了与Internet的远程无线连接和电子邮件的发送问题.该系统主要用于对远程移动或固定目标的自动信息采集和实时监控.     

基于SP接入的无线测控系统

借助内容提供商SP的运行平台构建基于短信的无线测控系统,抛弃了传统的手机对手机的通信模式,而将前端改为SP接入,并且给链路上的短信封装了灵活的通信协议,从而在一定程序上提高了系统的整体性能,具有良好的可扩展性和移植性。