Cabletron Systems CSX200 User Manual

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

Contents

The Bridge Port Forwarding Statistics Window3-37CSX Bridge ViewViewing Source Routing Frame Type StatisticsA Source Routing bridge uses various broadcast messages to determine theoptimum route for a frame, so there are a few more frame statistics to view. Whendisplaying Source Routing rather than Transparent Bridging information, theStatistics window activates the Frame Breakdown button, which lets you viewframe type statistics as either absolute values or as slices of a pie chart.To view Source Routing frame type statistics:1. In the SR Statistics window, click mouse button 1 on the Frame TypeBreakdown button.SR Frame types include the following:Total Frames ReceivedThe total number of frames, of all types, received at the selected port.Spec FramesSpecifically routed frames. These frames have data and routing information andare following a known route from source to destination.APE FramesWhen a sending station needs to determine the best route to an intendeddestination, it transmits an APE (All Paths Explorer) frame. The APE framecontains no routing information; it is propagated along all available paths to thedestination station, which then sends specifically routed frames as replies back tothe source. The first reply received by the original sending station is consideredthe most efficient route and is used in subsequent transmissions.STE FramesSpanning Tree Explorer frames, also known as Single Route Broadcast frames,follow the topology established by the Spanning Tree Algorithm. This specificallyrouted frame can be used by end stations, instead of the APE frame.NOTEDefinitions for the port summary statistics are included in the next section, which definesthe types of frame statistics available via the Frame Type Breakdown button.TIPThe statistics shown in the Bridge Port Statistics window reflect a “snapshot” of thestatistics from the time the window was opened. To refresh the statistics, you must closethis window and open it again.