Cabletron Systems CSX200 User Manual

Also see for SPECTRUM: User guide User guide User guide User guide Guide

Contents

CSX Bridge View3-2Accessing the Bridge Traffic View WindowAbout Transparent BridgingIndividual Transparent bridges monitor packet traffic on attached networksegments to learn where end stations reside in relation to each segment bymapping the Source Address of each received frame to the port (and segment) itwas detected on. This information gets stored in the bridge’s Filtering Database.When in the Forwarding state, the bridge compares a packet’s destination addressto the information in the Filtering Database to determine if the packet should beforwarded to another network segment or filtered (i.e., not forwarded). A bridgefilters a packet if it determines that the packet’s destination address exists on thesame side of the bridge as the source address.If two or more bridges are connected to the same Ethernet LAN segment —placed in parallel — only a single bridge must be allowed to forward data framesonto that segment. If two or more bridges were forwarding data frames onto thesame Ethernet segment, the network would soon be flooded. With a data loop inthe topology, bridges would erroneously associate a single source address withmultiple bridge ports, and keep proliferating data by forwarding packets inresponse to the ever-changing (but incorrect) information stored in their FilteringDatabase.To avoid such data storms, Transparent bridges communicate with one anotheron the network by exchanging Bridge Protocol Data Units (BPDUs) to determinethe network topology and collectively implement a Spanning Tree Algorithm(STA) that selects a controlling bridge for each LAN segment; this ensures thatonly a single data route exists between any two end stations and that topologyinformation remains current.Accessing the Bridge Traffic View WindowThere are two ways to access the CSX Bridge View.from the icon:1. Click on the appropriate device icon to display the icon menu.2. Drag down to Bridge-View and release.from the command line (stand-alone mode):1. From the appropriate directory type:spmarun bridge