ZyXEL GS2200-8 User Guide - Page 111

Chapter 13 Spanning Tree Protocol predefined interval (Max Age), the bridge assumes that the link to the root bridge is down. This bridge then initiates negotiations with other bridges to reconfigure the network to re-establish a valid network topology. STP Port States STP assigns five port states to eliminate packet looping. A bridge port is not allowed to go directly from blocking state to forwarding state so as to eliminate transient loops. Table 28 STP Port States PORT STATE DESCRIPTION Disabled STP is disabled (default). Blocking Only configuration and management BPDUs are received and processed. Listening All BPDUs are received and processed. Learning Forwarding Note: The listening state does not exist in RSTP. All BPDUs are received and processed. Information frames are submitted to the learning process but not forwarded. All BPDUs are received and processed. All information frames are received and forwarded. Multiple RSTP MRSTP (Multiple RSTP) is ZyXEL's proprietary feature that is compatible with RSTP and STP. With MRSTP, you can have more than one spanning tree on your Switch and assign port(s) to each tree. Each spanning tree operates independently with its own bridge information. In the following example, there are two RSTP instances (MRSTP 1 and MRSTP2) on switch A. To set up MRSTP, activate MRSTP on the Switch and specify which port(s) belong to which spanning tree. Note: Each port can belong to one STP tree only. Figure 68 MRSTP Network Example GS2200-8/24 User's Guide 111