Autonomic group Computing in Peer-to-Peer Systems

信息系统的体系结构正在从传统的客户-服务器(CS)模式向新型的对等(P2P)模式转变。P2P系统由多台对等计算机组成，每台计算机都可以扮演客户端和服务器的角色。此外，P2P系统是可扩展的，即大量的计算机在从个人计算机到超级计算机的各种类型的计算机中互联。此外，P2P系统本质上是开放的，即计算机自主地加入和离开系统，并且每台计算机支持的服务类型和服务质量(Qos)都在变化。应用程序要求系统支持各种类型的服务需求。在这些P2P系统中，由于P2P系统的可扩展性和开放性，很难甚至不可能像传统系统那样采用集中控制的方案来管理每台组件计算机。我们必须开发新的概念和体系结构来设计、实现、维护和…在这项研究中，我们首先讨论了一组可伸缩的大量对等进程的分层模型。组是各种类型的计算机上的多个对等进程的集合，这些计算机在像Internet这样的网络中互连。组中的每个对等进程向多个对等进程发送消息，同时从多个对等进程接收消息。消息需要按顺序/完全传递到组中的进程。对于一个组中的n个进程，通信和计算开销为O(n^*n)。为了减少开销，一个组由通过网关进程互连的子组组成。因为子组比整个组小，所以我们可以减少开销。此外，每个对等进程都必须检测支持所需服务的对等进程。我们考虑多媒体对象。为了检测目标进程，每个对等进程都会询问熟人进程。在这里，讨论对等进程可以在多大程度上信任每个熟人进程至关重要。我们从服务质量和访问权限的角度定义了每个熟人节点的可信性。今年，我们讨论了如何在我们第一年开发的基于P2P的体系结构上实现数据库应用。在本研究中，数据库应用是在移动代理中实现的。特别是，使用移动代理可以实现事务的容错，因为事务可以从故障计算机转移到其他可操作的计算机上。我们在IJHPCN和Join等国际期刊上以及IEEE Aina、ICPADS、ISORC、ISM和DEXA等国际会议上发表了关于这一研究的论文。较少

The architecture of information system has been changing from the traditional client-server (CS) model to new type, peer-to-peer (P2P) ones. The P2P system is composed of peer computers, where each computer can play every role of client and server. In addition, the P2P system is scalable, i.e. a large number of computers are interconnected in various types of computers, ranging from personal computers to super computers. In addition, the P2P system is in nature open, i.e. computers autonomously join and leave the system, and the type of service and quality of service (QoS) supported by each computer are changing. Applications require the system to support various types of service requirements. In these P2P systems, it is difficult, maybe impossible to manage every component computer in a centralized control scheme as taken in traditional systems due to the scalability and openness of the P2P system. We have to develop novel concepts and architecture to design, implement, maintain, and … More operate the P2P system.In this research, we first discuss a hierarchical model for a scalable group of large number of peer processes. A group is a collection of multiple peer processes on various types of computers which are interconnected in networks like the Internet. Each peer process in a group send a message to multiple peer processes while receiving messages from multiple peer processes. Messages are required to be causally/totally delivered to processes in a group. The communication and computation overheads are O(n^*n) for the number n of processes in a group. In order to reduce the overhead, a group is composed of subgroups which are interconnected through gateway processes. Since a subgroup is smaller than the whole group, we can reduce the overhead. In addition, each peer process has to detect peer processes which support required service. We consider multimedia objects. In order to detect target processes, each peer process ask the acquaintance processes. Here, it is critical to discuss how much a peer process can trust each acquaintance process. We define the trustworthiness of each acquaintance peer in terms of QoS, and access right.This year, we discuss how to realize database applications on the P2P based architecture which we developed in the first year. In this research, database applications are realized in mobile agents. Especially, transactions can be fault-tolerant by using the mobile agents because the transactions can move to other operational computers from faulty computers.We published papers on the research in international journals like IJHPCN and JOIN and international conferences like IEEE AINA, ICPADS, ISORC, ISM, and DEXA. Less