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本文讨论用来测试新的自稳定桥协议操作的仿真技术并将其性能与现有的工业标准进行比较[4,24]。尤其是,有关把作为工业标准的IEEE802.1(D)生成树算法[25,26]与新近提出的以回路检测包为基础的自稳定桥协议相比较的试验研究。为这项工作选择的语言是Pascal Plus,它是提供并发程序结构(如进程和监控程序)的标准Pascal的扩展。强调通信和网络中的仿真作用并评述上述工作。研究中的问题是关于叫做桥的装置的使用,连接两个或多个局部区域网络(LAN)以便形成叫做多LAN的大型互连系统。近年来,通信系统的可靠性成为网络管理者最最关心的头等大事。为了增加多LAN范围的可靠性,通常安装并行桥,由此为相邻LAN间提供交替通道。这种方法的固有问题是可能导致用多个桥传送同一信息量给桥连接的邻接LAN和从邻接LAN传出该信息量。这可能产生重复包、不必要的通信负载,并且在某些情况形成无限的信息包循环,以致使它们跨接的信道性能急剧下降。IEEE802.1委员会已规定了解决这些问题的算法,称为生成树算法。虽然基本的物理拓扑可以是一个任意的网格,但这个方案把拓扑修剪成无循环的逻辑拓扑。该方案可这样实现:为整个系统选择单一的根(ROOT)桥,接着为每个LAN选择单一的标志桥(主动的),而所有其他并行桥处于备用状态(被动的)
This article discusses the simulation techniques used to test the operation of a new self-stabilizing bridge protocol and compares its performance with existing industry standards [4,24]. In particular, experimental studies comparing the IEEE802.1 (D) spanning tree algorithm [25, 26], which is an industry standard, with the recently proposed self-stabilizing bridge protocol based on a loop detection package. The language of choice for this work is Pascal Plus, which is a standard Pascal extension that provides concurrent program structures such as processes and monitors. Emphasize the role of simulations in communications and networks and comment on the above. The question under study is about the use of devices called bridges to connect two or more local area networks (LANs) to form a large interconnect system called a multi-LAN. In recent years, the reliability of communication systems has become the number one priority for network managers. In order to increase the reliability of multiple LAN ranges, it is common to install parallel bridges, thereby providing alternate paths between adjacent LANs. The inherent problem with this approach is that it may result in multiple bridges transmitting the same amount of information to and from the adjoining LAN of the bridge. This can result in duplicate packets, unnecessary traffic load, and in some cases endless packet cycles, causing the performance of their jumpered channels to drop dramatically. The IEEE802.1 committee has specified an algorithm for solving these problems, called a spanning tree algorithm. Although the basic physical topology can be an arbitrary grid, this scheme prunes the topology into a loop-free logical topology. This solution can be implemented by selecting a single ROOT bridge for the entire system, then selecting a single marker bridge (active) for each LAN, and all other parallel bridges in standby (passive)