Learning State - Cisco 7609 Configuration Manual

Understanding How STP Works

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.
Figure 15-5 Interface 2 in Learning State
A Layer 2 LAN port in the learning state performs as follows:
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Cisco 7600 Series Router Cisco IOS Software Configuration Guide—12.1E
15-10
All segment
frames
Port 1
Station
addresses
BPDUs
Filtering System
database module
Station
addresses BPDUs
Data
frames
Port 2
Learning
BPDU and network
management frames
Discards frames received from the attached segment.
Discards frames switched from another port for forwarding.
Incorporates end station location into its address database.
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.
Figure 15-5
Forwarding
Network
management
and data frames
Frame
forwarding
Network
management
frames
All segment
frames
Chapter 15 Configuring STP and IEEE 802.1s MST
shows a Layer 2 LAN port in the
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