11-6 CHAPTER 11: ADMINISTERING BRIDGE PORTS
Frame Processing and
Bridge Port Statistics
All frames received on a physical (Ethernet or FDDI) interface and not
explicitly directed to the Switch 2200 are delivered to the corresponding
bridge port. A frame is then either forwarded to another bridge port or
discarded. A frame might be discarded for the following reasons:
■ The destination station is on the same segment as the source station.
■ The receive bridge port is blocked.
■ There is some problem with the frame.
■ A user-defined packet filter indicated that the frame should not be
forwarded.
Figure 11-1 shows the order in which the discard decisions are made.
Figure 11-1 How Frame Processing Affects Receive Bridge Port Statistics
A frame forwarded to a bridge port is transmitted onto a physical interface
unless it is discarded. A frame might be discarded for the following reasons:
■ The transmit bridge port is blocked.
■ The frame is too large for the corresponding physical interface.
■ A user-defined packet filter indicated that the frame should not be
forwarded.
xFrames
ameSegDiscs
xBlockedDiscs
xSecurityDiscs
xErrorDiscs
xOtherDiscs
xMcastFilters
xAllFilters
xForwardUcasts
xFloodUcasts
xForwardMcasts
Frames received on this bridge port
Frames discarded because frame not valid for
bridging
Frames forwarded by this bridge port
processing of frames
eceive Bridge Port Statistics
from Physical
Interface
=
Frames discarded because of user-defined
packet filter
Frames discarded because source and
destination stations on same segment
Frames discarded because receive bridge port
blocked
