Frame Processing And Fddi Mac Statistics - 3Com LANPLEX 6000 User Manual

9-22 C 9: A
HAPTER DMINISTERING
FDDI R
ESOURCES

Frame Processing and FDDI MAC Statistics

All frames on the FDDI network are received promiscuously by an FDDI
MAC. A frame may be discarded, however, for the following reasons:
There is no buffer space available
The frame is in error
LLC service is disabled
This is an NSA Frame and the A-bit is set
Figure 9-2 shows the order in which these discard tests are made.
Receive Frame Statistics
rxFrames
noRxBuffers
errorCount
rxInternalErrs
rxDiscards
rxUcastFrames
rxMcastFrames
Figure 9-2 How Frame Processing Affects FDDI MAC Receive Frame Statistics
Frames are delivered to an FDDI MAC by bridges and management
applications. However, a frame may be discarded for the following reasons:
LLC Service is disabled
The FDDI ring is not operational
There is no room on the transmit queue
An error has occurred during frame transmission
Frames received from the network
Frames discarded because buffer space
was exhausted
Frames discarded because frame in error
Frames discarded because LLC Service
disabled or NSA frame with A-bit set
=
Frames delivered by this FDDI MAC
from FDDI
Network