Learning State - Cisco WS-SUP32-GE-3B - Supervisor Engine 32 Software Configuration Manual

Understanding How STP Works
Figure 17-4
A Layer 2 LAN port in the listening state performs as follows:
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Learning State

A Layer 2 LAN port in the learning state prepares to participate in frame forwarding. The Layer 2 LAN
port enters the learning state from the listening state.
learning state.
Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY
17-8
Interface 2 in Listening State
All segment
frames
Port 1
Station
addresses
BPDUs
Filtering System
database module
BPDUs
Data
frames
Port 2
Listening
BPDU and network
management frames
Discards frames received from the attached segment.
Discards frames switched from another LAN port for forwarding.
Does not incorporate end station location into its address database. (There is no learning at this
point, so there is no address database update.)
Receives BPDUs and directs them to the system module.
Receives, processes, and transmits BPDUs received from the system module.
Receives and responds to network management messages.
Forwarding
Network
management
and data frames
Frame
forwarding
Network
management
frames
All segment
frames
Figure 17-5
Chapter 17 Configuring STP and MST
shows a Layer 2 LAN port in the
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