FDDI Management

The FDDI MAC Meters window graphically and numerically displays the following statistics:

Frame Rate

Displays the total FDDI network activity, measured in frames per second. The Frame Rate includes frames, but not tokens.

Frame Error Rate

Displays the total number of MAC Frame errors detected by the module, measured in frames per second. An error frame is any received frame that does not meet frame validity criteria: each frame must have a starting delimiter, a frame control field, zero or more additional data symbols, and an ending delimiter. The detecting station sets the Frame Status Error Indicator, and repeats the packet. Subsequent receiving stations do not count the frame as an error frame.

Lost Frame Rate

Displays the number of MAC PDUs (Protocol Data Units include both tokens and frames) that contain an unknown error, measured in frames per second. When the MAC encounters a frame of this type — whose validity is in doubt — it increments the Lost Frame counter and strips the remainder of the frame from the ring, replacing it with idle symbols.

Frame Error Ratio

Where the other meters show a snapshot of network performance, the Frame Error Ratio compares the total number of Lost and Error frames to total number of received frames, displaying a ratio which provides an overall picture of network health.

To exit the FDDI MAC Meters window, click .

Viewing FDDI MAC Graphs

If you are running SPMA in conjunction with HP Network Node Manager or IBM NetView, the Port Configuration window will include a MAC Graph button; select this button to display FDDI variables for the selected port via the graphing application provided by your network management platform.

If you are running SPMA in conjunction with SunNet Manager or in a stand-alone mode, no graphing capabilities are available, and no graph-related options will appear.

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SMT/MAC Configuration

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Cabletron Systems 7C04-R, 7C03 manual Frame Error Rate, Lost Frame Rate, Frame Error Ratio, Viewing Fddi MAC Graphs