20-24 Sm artSwit ch 1800 4.0 U ser Gui de, Rev 01
BPDU frames will be received or transmitted, to allow the port to get its
status into the spanning tree algorithm. The port will leave this state when
the Bridge Fo rwar d De l ay timer (see page 16-4) expires. If the port is
selected as Root or Designated port, it will enter Forwar ding s tat e. I f t he
port is not selected as Root or Designated port, it will en ter Block ing state.
A Root port is the one selected by the spanning tree algo rith m as
the port used to reach the root bridge (which is the least-cost
bridge in a link). A Designated port is the port that connects to
the least-cost path to the root bridge.
◆Learni ng – BPDUs ("Hello" messages) are being sent b etween bridge s, and
the spanning tree algorithm is being updated. The port will leave this state
when the Bridge Forw ard D elay timer (see page 16-4) expires. If the port is
selected as Root or Designated port, it will enter Forwar ding s tat e. I f t he
port is not selected as Root or Designated port, it will enter Blocking state.
◆Forwar ding – the Bridge port is participating in bridging of frames, as well
as ongo ing lear ning and updat ing of t he spa nn ing tre e algo rithm. If the
algorithm redesignates the port as non-root or non-designated, the port
might enter Blocki ng state.
◆Blocki ng – th e Bridg e por t has not been s ele cted as Root or Designated, and
is transitioning to the Listening state.
●Rcv/Xmit – are the cumulative bytes received/transmitted on the Bridge port.
Bridge Forwarding Table
The Bri dge Forw a rding T able i s us ed to m atch MAC addre s s e s with Bridge po rts on
which to forward frames. If an address is not found in the table, the frame will be for-
warded out all Bridge ports except those configured for native LLC-2.
All MAC addresses are in non-canonical (Token Ring) format.
As a frame is received, its source and destina tion MAC addresses will be added (if not
already there) to the table. (If received from a Token Ring, the addresses will be bit-
swapped [described under "Host MAC Address" on page 9-22] when added to the
table.) The SmartSwit ch 1800 softwa re co ntains a set of r eserve d MAC address es that
are considered "static," and will always be i n the table. The remaining e ntries are con-
sidered "dynamic," and will remain in the table for the time period configured as the
Bridge Ag ing Ti m e r in Bridge Node Defaults .
Press [B] at the Bridge Status Displays Menu to display a forwar ding table for all MAC
addresses received on Bridge ports in the node.