17

Spanning Tree Protocol

17.1 Overview

(R)STP detects and breaks network loops and provides backup links between switches, bridges or routers. It allows a Switch to interact with other (R)STP- compliant switches in your network to ensure that only one path exists between any two stations on the network.

The Switch supports Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP) as defined in the following standards.

•IEEE 802.1D Spanning Tree Protocol

•IEEE 802.1w Rapid Spanning Tree Protocol

17.2What You Can DO

•Use the General Settings screen (Section 17.4 on page 97) to enable and configure STP.

•Use the STP Status screen (Section 17.5 on page 98) to check the STP current status.

17.3What You Need to Know

The Switch uses IEEE 802.1w RSTP (Rapid Spanning Tree Protocol) that allows faster convergence of the spanning tree than STP (while also being backwards compatible with STP-only aware bridges). In RSTP, topology change information is directly propagated throughout the network from the device that generates the topology change. In STP, a longer delay is required as the device that causes a topology change first notifies the root bridge and then the root bridge notifies the network. Both RSTP and STP flush unwanted learned addresses from the filtering database. In RSTP, the port states are Discarding, Learning, and Forwarding.

Note: In this user’s guide, “STP” refers to both STP and RSTP.

 

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GS1510 Series User’s Guide