Flashcards in Ch. 5: Analyzing Etheret LAN Switching Deck (17)
An Ethernet frame sent to destination address FFFF.FFF F.FFFF, meaning that the frame should be delivered to all hosts on that LAN.
known unicast frame
An Ethernet frame whose destination MAC address is listed in a switch’s MAC address table, so the switch will forward the frame out the one port associated with that entry in the MAC address table.
Spanning Tree Protocol (STP)
A protocol defined by IEEE standard 802.ID. Allows switches and bridges to create a redundant LAN, with the protocol dynamically causing some ports to block traffic, so that the bridge/switch forwarding logic will not cause frames to loop indefinitely around the LAN.
unknown unicast frame
An Ethernet frame whose destination MAC address is not listed in a switch’s MAC address table, so the switch must flood the frame.
MAC address table
A table of forwarding information held by a Layer 2 switch, built dynamically by listening to incoming frames and used by the switch to match frames to make decisions about where to forward the frame.
To send a frame received in one interface out another interface, toward its ultimate destination.
The result of the LAN switch forwarding process for broadcasts and unknown unicast frames. Switches forward these frames out all interfaces, except the interface in which the frame arrived. Switches also flood multicasts by default, although this behavior can be changed.
show mac address-table
Shows all MAC table entries of all typed
show mac address-table dynamic
Shows all dynamically learned MAC table entries
show mac address-table dynamic vlan (vlan-id)
Shows all dynamically learned MAC table entries in that VLAN
show mac address-table dynamic address (mac address)
Shows the dynamically learned MAC table entries with that MAC address
show mac address-table dynamic interface (interface-id)
Shows all dynamically learned MAC table entries associated with that interface
show mac address-table count
Shows the number of entries in the MAC table and the total number of remaining empty slots in the MAC table
show mac address-table aging-time
Shows the global and per-VLAN aging timeout for inactive MAC table entries
clear mac address-table dynamic
Empties the MAC table of all dynamic entries
show interfaces status
Lists one line per interface on the switch, with basic status and operating information for each