Learning State - Cisco WS-C2948G-GE-TX Configuration Manual

Understanding How STPs Work
Figure 7-4
A port in the listening state performs as follows:
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•
•
•
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Learning State

A port in the learning state prepares to participate in frame forwarding. The port enters the learning state
from the listening state.
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
7-8
Port 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 that are received from the attached segment
Discards frames that are switched from another port for forwarding
Does not incorporate 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
Processes BPDUs that are received from the system module
Receives and responds to network management messages
Figure 7-5
Forwarding
Network
management
and data frames
Frame
forwarding
Network
management
frames
All segment
frames
shows a port in the learning state.
Chapter 7 Configuring Spanning Tree
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