以太网交换机EAPS系统的设计

【作者】 毕汝超；

【导师】 胡飞；

【作者基本信息】 西北工业大学 ， 软件工程， 2007， 硕士

【摘要】 随着以太网逐步向城域网、甚至广域网方向发展，越来越多的运营商逐步将其作为承载网进行建设与运营。作为以太网的载体——以太网交换机正在向着多功能、多层定位的方向发展。 2000系列以太网交换机是中兴通讯股份有限公司最新研发的、具备路由功能的以太网交换机，定位于企业网的核心层和汇聚层，能够应用于运营商网络，作为电信城域网的汇聚交换机、接入交换机来使用。 在实际组网应用中，以太网环路的出现会导致“广播风暴”现象(即大量广播包阻塞网络链路)，严重影响网络性能。IEEE制定的生成树协议虽然能够解决这一问题，但其收敛速度过慢，无法适应核心网络的需求。在2000系列以太网交换机中，通过内置EAPS(Ethernet Automatic Protection Switching，以太网自环保护切换)模块的方法，可以避免“广播风暴”的出现，并且能够在网络动荡中，产生毫秒级别的收敛速度。 本文结合2000系列以太网交换机系统软件的整体设计，探讨了EAPS以太网自环保护子模块的设计开发技术，详细阐述了开发平台、系统架构、总体设计等内容，并讨论了以太网基本原理、VLAN技术等相关知识；使用内置EAPS方法，可以避免自环的出现，在以太网环路中，通过消息传递、端口阻塞控制等手段避免了“广播风暴”，并实现了对网络故障的监测。EAPS方法收敛速度快，能够满足电信级城域网组建的需求。更多还原

【Abstract】 The Ethernet is gradually developed to the MAN and even WAN, which is taken as core network by more and more costomers.The Ethernet Switch is now being developed to multifunction and multi-level orientation.The 2000 series Ethernet Switch was designed by ZTE corporation up to date, which was located in the core networking. And it also could be used in WAN and MAN.In practical networking, there is "Broadcast storm(the network is blocked by too many broadcast packet)"as a result of ethernet ring, which seriously effect the network cap- ability. Although the STP(Spanning Tree Protocol) which is constituted by IEEE can solved "Broadcast storm", but its convergence is so slow that can not adapt the requirement of core network.EAPS( Ethernet Automatic Protection Switching) is the subsystem of ring auto-detect and protection in the system of the 2000 series Ethernet Switch, which is used in enterprise networks. With EAPS subsystem, 2000 series Ethernet Switch, could avoid the emergence of broadcast storm", and its convergence speed can be controlled within 50 milliseconds.This thesis will introduce the EAPS design in combine of 2000 series Ethernet Switch software system. We will expatiate the design roof、the system structure and the total design in detail. We also discuss the Ethernet theory, Vlan technology,etc. In Ethernet ring, using the principle of EAPS, the "broadcast storm" can be avoid through message pass、port block and domain. Its convergence speed could fit the requirement of the core network.更多还原