Cisco WS-C4003 Software Guide - Page 105

Chapter 7 Configuring Spanning Tree How Spanning Tree Protocols Work Learning State A port in the learning state prepares to participate in frame forwarding. The port enters the learning state from the listening state. Figure 7-5 shows a port in the learning state. Figure 7-5 Port 2 in Learning State All segment frames Forwarding Station addresses Port 1 BPDUs Network management and data frames Filtering database System module Frame forwarding Station addresses Data frames BPDUs Port 2 Network management frames S5694 Learning All segment frames BPDU and network management frames A port in the learning state performs as follows: • Discards frames received from the attached segment. • Discards frames switched from another port for forwarding. • Incorporates 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. 78-12647-02 Software Configuration Guide-Catalyst 4000 Family, Catalyst 2948G, Catalyst 2980G, Releases 6.3 and 6.4 7-9